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Systems to Intercept Calls from Contraband Cell Phones in California Prisons, CCST, 2012

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The Effie cy o
S stems t nter pt alls from
Cbntraban Cel h es in

Youla

California Council on Science and Technology
May 2012

The Efficacy of Managed
Access Systems to Intercept
Calls from Contraband Cell
Phones in California Prisons

May 2012
California Council on Science and Technology

ACKNOWLEDGEMENTS
We would like to thank the many people who provided input towards the completion of this report.
Without the insightful feedback that these individuals generously provided, this report could not have been
completed. We would like to give special thanks to Charles Harper, CCST Board Member and chair of the
project team that developed this report, and S. Pete Worden, director of the NASA Ames Research Center,
who provided technical experts who contributed to and reviewed this report.
This report was conducted with the oversight of a CCST Contraband Cell Phones in Prisons Project Team,
whose members include: Charles Harper, chair of the CCST Project Team, Patrick Diamond, Brian W. Carver,
with technical expert input from NASA Ames Research Center via S. Pete Worden, director, NASA Ames
Research Center, Don Beddell, Robert Cates, Deb Feng, Ray Gilstrap, William Hunt, and William Notley,
James Williams, and the Charles Stark Draper Laboratory via David Goldstein, senior systems engineer. We
also thank Lora Lee Martin, CCST Director Sacramento Office, for the overall project coordination resulting
in this report. We express gratitude to CCST’s members and colleagues for their many contributions to
the report and substantive peer reviews that were conducted. A more complete list of the project team is
included in Appendix 1.
This document was prepared under a grant from FEMA’s Grant Programs Directorate, U.S. Department of
Homeland Security. Points of view or opinions expressed in this document are those of the authors and do
not necessarily represent the official position or policies of FEMA’s Grant Programs Directorate or the U.S.
Department of Homeland Security.
COPYRIGHT
Copyright 2012 by the California Council on Science and Technology. Library of Congress
Cataloging Number in Publications Data Main Entry Under Title:
The Efficacy of Managed Access Systems to Intercept Calls
from Contraband Cell Phones in California Prisons
May 2012
ISBN 13: 978-1-930117-63-1
The California Council on Science and Technology (CCST) is an independent non-profit 501(c)3 organization
established in 1988 at the request of the California State Government. CCST’s mission is to improve science
and technology policy and application in California by proposing programs, conducting analyses, and
recommending public policies and initiatives that will maintain California’s technological leadership and a
vigorous economy.
Note: The California Council on Science and Technology has made every reasonable effort to assure the
accuracy of the information in this publication. However, the contents of this publication are subject to
changes, omissions, and errors, and CCST does not accept responsibility for any inaccuracies that may
occur.

For questions or comments on this publication contact:
California Council on Science and Technology
1130 K. Street, Suite 280
Sacramento, California 95814
(916) 492-0996
ccst@ccst.us

Table of Contents
Transmittal Letter from CCST ...................................................................................................... 1
Letter of Request from the California Legislature ............................................................................ 3
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.

Key Report Findings ................................................................................................................ 6
Recommendations .................................................................................................................. 7
Legislative Request ................................................................................................................. 8
Project Approach .................................................................................................................... 8
Statement of Problem ............................................................................................................. 9
Legal and Regulatory Context .............................................................................................. 10
Overview of Contraband Cell Phone and Wireless Technology ............................................ 12
Stopping Illicit Cell Phone Use in Prisons ............................................................................ 13
What is Happening Nationally and in Other States .............................................................. 15
Review of Managed Access System (MAS) Technology ......................................................... 15
Limitations of Managed Access System Technology ............................................................. 20
Can California Develop a Successful MAS Model? .............................................................. 21
Benefits of a Robust Pilot Project ......................................................................................... 23
Third Party Consortium Oversight ......................................................................................... 24

Appendix 1: CCST Project Team Members .................................................................................. 26
Appendix 2: CCST Letter to Senators Identifying IFB Issues of Concern
	
(October 29, 2011) ..................................................................................................27
Appendix 3: Letter from Senators to Matthew Cate, Secretary, California
	
Department of Corrections and Rehabilitation (CDCR) Conveying
	
Issues from CCST’s October 2011 Letter .................................................................. 29
Appendix 4: Preliminary List of Issues Identified with Status Updates............................................34
Appendix 5: April 11, 2012 Letter from Senators to Secretary Cates, California 	
	
	
Department of Corrections and Rehabilitation (CDCR) Conveying
	
Notice of the Immanence of the CCST report .......................................................... 36
Appendix 6: An Analysis of Barriers to Implementing Airport-Style Security at all
	
Points of Entry to California’s Correctional Institutions, January 2012....................... 38
Appendix 7: Federal Bureau of Prisons Electronic Search Protocol ............................................. 45
Appendix 8: What is Radio Frequency (RF) Communications - The Idea of Waves
	
as Energy...................................................................................................................47
Appendix 9: Technical Evaluation Report: CCST Challenges, Sandia National
	
Laboratory, April 2012 ............................................................................................ 63
Bibliography - Source Documents ................................................................................................ 68
Glossary...................................................................................................................................... 70

ABC

Transmittal Letter from CCST Regarding Report

1

2

Letter of Request from the California Legislature

3

4

5

1.

Key Report Findings
Contraband Cell Phones in Prisons are a Growing State and National Security Issue
In 2011, approximately 15,000 contraband cell phones were confiscated at the California
State Prisons.1 This represents only the cell phones found, not all phones in the facilities.
Though the phones may be used for communications with family or for entertainment,
they can also be used for illegal or dangerous activities. This California Council on
Science and Technology (CCST) report acknowledges that a suite of technological and
non-technological approaches to address this problem is warranted.
Inconsistent Screening at State Prisons
Screening of California Department of Corrections and Rehabilitation (CDCR) personnel
and visitors entering and leaving the prisons was found to be less rigorous than screening
found at a normal airport security screening access point. During visits to several prison
facilities, unscreened items, e.g., purses, duffle bags, and large soft-sided ice chests,
were seen both entering and leaving CDCR facilities without x-ray, metal detection, or
thorough manual searches.
Existing and Evolving Complexities of Signal Capture
There are significant technological challenges to effective implementation of MAS and
other approaches based on the evolving capabilities of mobile devices. This includes
capabilities seen in mobile devices in the marketplace today and the anticipated future
capabilities of commercial mobile devices including satellite phones.2 This complexity
argues for an investment in securing the contraband devices themselves rather than
reliance on technology to block the communication.
MAS Technology Not Yet Proven for Prison Environment
CCST finds that the Managed Access System (MAS) technology of today is not mature
enough for immediate large-scale deployments such as that proposed by CDCR at
California’s 33 state prisons.
MAS Efficacy Protocols Not Defined
CCST notes that there is no evidence that CDCR has fully or reliably identified the size of
the contraband cell phone problem or a mechanism to determine the efficacy of a MAS
when deployed.
Baseline Benchmarks Needed
To evaluate the effectiveness of an installed MAS, a baseline measure of contraband cell
phone usage must be done prior to implementing a MAS strategy.

1 CDCR personnel provided these numbers orally to the CCST project team at a CDCR briefing on January 5, 2012 held
at the California Senate Office of Research and again at a prison tour on January 10th, 2012.
2 Technical Evaluation Report: CCST Challenges, Sandia National Laboratories, April 19, 2012 (See Appendix 9)

6

2.

Recommendations
Alternative options for mitigating Contraband Cell Phones should be considered before
adoption of MAS or use of other technologies
MAS, even if successfully designed and deployed, is not enough. Other options (technical
and non technical) for managing the cell phone problem should be aggressively pursued.
Undertake a comparative benefit/cost for these other options that include:
1.	 Implement the Federal Prisons Screening Protocols in California Prisons- Airport
like security screening at all entrances for all personnel and all items.
2.	 Conduct thorough searches of all items, vehicles, and personnel at all sally port
entrances using all available means to identify contraband.
3.	 Test the use of other technologies within confined prison locations, (e.g., prison
cell block or technologies to identify and locate transmissions) to intercept and
dead-end unauthorized cell phone calls.
4.	 Engage the cell phone carriers to identify use of their technology and to deny
connections for unregistered cell phones from within prison locations.
5.	 Pursue, in coordination with other states and federal legislators, prison specific
exceptions to Federal Communications Commission (FCC) anti jamming
regulations. This approach would be complementary to the federal government’s
2012 agreement with vendors to disable stolen cell phones.
However, if MAS is pursued then pursue it wisely: Independently test one or more
pilots before contracting for a MAS.
An independent consortium should be created to develop and oversee the design and
deployment of a MAS Pilot Network. The consortium should include technical expertise
from research organizations, cellular network operators, and from the California
Legislature, (e.g., the Senate Office of Research). The consortium should be overseen
and managed by an independent third party with technical credentials suited to the task.
Design, Install and Monitor MAS Pilot(s).
One or more pilot projects should be installed and operated for at least 12 months prior
to contracting for deployment of a CDCR MAS to provide;
1.	 Identifiable measures of efficacy for the MAS regarding the volume of cell phone
usage before and volume of blocked calls after the MAS deployment.
2.	 A working template for implementing the MAS in the demanding environment of
a correctional institution.
3.	 The operational expertise of cell phone network operation within the CDCR and/
or California Technology Agency (CTA).
4.	 A mechanism for third party oversight of the MAS operation and conformance
to wireless operations standards including a mechanism to measure vendor
compliance to emerging wireless technology and deployment modernization
techniques.

7

3.

Legislative Request

This report is in response to a July 7, 2011 letter of request to the California Council on Science
and Technology (CCST) from four California State Senators (Senators Elaine Alquist, Loni Hancock,
Christine Kehoe and Alex Padilla). As detailed in the front of this report, the senators asked CCST
to provide input on the best way to prevent cell phones from getting into the hands of inmates and,
if they do, how best to prevent calls from being completed without impairing the ability of prison
authorities to make and receive official business cell phone calls. In addition, they asked CCST to
undertake a study on the feasibility of Managed Access Systems (MAS) technology as an effective
strategy to curtail the use of contraband cell phones in the California State Prisons. In their letter
the senators indicated that the California Department of Corrections and Rehabilitation (CDCR) had
issued an Invitation for Bid (IFB),3 for replacement of the Inmate and Wards Telephone System (IWTS)
including a requirement and specifications for the installation and operation of a MAS at each of
the 33 State Prison sites to combat the problem of contraband cell phones in the California State
Prison system. In exchange for the MAS system, the successful bidder/vendor would receive the right
to operate and collect revenues from the IWTS landline phone system. Across all of the California
prison facilities this IWTS use is estimated to be approximately 99 million minutes of landline calls.
The CDCR IFB defines in detail the required parameters for the IWTS and the MAS.

4.

Project Approach

CCST convened a Contraband Cell Phone Project Team comprised of CCST council and board
members supplemented with additional experts (see Appendix 1 for Project Team Members). The
CCST Project Team reviewed in detail the CDCR IFB calling for MAS. From that review, the team
identified 12 issues of concern that they conveyed by letter to the State Senators requesting the
report (see Appendix 2, CCST Letter to Senators, October 28, 2011). The Senators then transmitted
a letter expressing concern to the CDCR (see Appendix 3). Some, but not all, of these issues were
subsequently addressed in IFB modifications or clarifications. Appendix 4 contains a summary and
status table of these issues. A second letter was transmitted to CDCR on April 11, 2012 by the Senators
conveying the immanence of the CCST report and suggesting that the information contained in the
document would assist CDCR (see Appendix 5). However, CDCR moved ahead with a contract for
MAS on April 16, 2012.
The project Team identified and reviewed many publications and postings about MAS and contraband
cell phones in prisons and contacted numerous experts, users, and vendors to understand their
current capabilities and limitations. CCST Project Team members met with representatives from
CDCR and the California Technology Agency (CTA) for a contraband cell phone interdiction briefing
on January 5, 2012, lead by CDCR Cell Phone Interdiction Manager, Tim Vice.
It is important to note that CCST has not undertaken primary research of its own to address these
issues. This response is limited to soliciting input from technical experts and to reviewing and
evaluating available information from past and current materials related to MAS and contraband cell
phones. This report has been approved by the CCST Project Team and has been subject to the CCST’s
substantive peer review process.
In January 2012, members of CCST’s technical team visited two California prisons (Solano State
Prison and the California Medical Facility); a separate visit to Folsom State Prison in March also
3	 Invitation for Bid (IFB) was issued by the California Technology Agency on behalf of CDCR on July 7, 2011; IFB 11126805

8

provided some insights. In discussions with inmates, the CCST team was told that contraband cell
phones are paid for in cash, outside the prison, before the phones are smuggled into the prison and
delivery is made. It is unclear how many cell phones are being smuggled in; however, the fact that
15,000 cell phones were confiscated last year, as reported to the project team by CDCR personnel4,
means that many more are likely making their way into the prisons undetected. CDCR indicated
that its ability to detect this illegal activity is limited due to the large and varied communities of
people entering and leaving the prisons and the many access points into the confinement area. Once
contraband phones are inside the prison confinement areas, CDCR has also indicated that their
ability to detect cell phone presence is limited. Inmates have numerous ways to hide them, and
the CCST team was told that the cell phones are generally used after “lights out” in the confinement
areas. The CDCR is exploring the MAS as a potential way to neutralize the smuggled phones, by
making them essentially inoperable within the prison confinement area.
Though the CCST Project Team reviewed the entire referenced IFB, it focused specifically on the
MAS portion of the IFB. This report details the technical and operational issues of the MAS as the
principal approach to help mitigate the contraband cell phone problem. However, we note that
there are other technological and non-technological methods that should be considered.
The report identifies and provides details about the few known vendors of these systems. It also
identifies performance issues relating to the efficacy of the MAS in mitigating contraband cell phone
operation and use.
For context, this report also summarizes the approach taken by the Federal Bureau of Prisons (FBOP)
to manage contraband cell phone issues at the point of entry into their facilities. The Federal Bureau
of Prisons has been instructed by the U.S. Government Accountability Office (GAO) to coordinate
with states to identify a uniform approach to addressing this problem.5
This report mainly addresses the issue of contraband cell phones using their native cellular capabilities,
including voice, text message and data services. Though mentioned in this report, the operation of
contraband cell phones using secondary communication capabilities such as point-to-point wireless
LAN (e.g. Wi-Fi) or short-range RF (e.g. Bluetooth) communications is not explored in great depth.

5.

Statement of Problem

Contraband cell phones are being smuggled into California State Prisons in large numbers.
According to the prisoners that the project team interviewed, the cell phones are used, in large part,
for communications with inmate family members and friends or for entertainment (e.g., gaming or
videos). However, the use of these contraband cell phones also has numerous negative effects as
reported by recent reports from the Federal Bureau of Prisons,6 U.S. Department of Commerce,7 and
several independent state corrections departments.8 These negative effects include illegal activities
such as drug deals, gang operations, victim harassment and instructions for ‘hits’.
4 At a CDCR briefing on January 5, 2012 held at the California Senate Office of Research and again at a prison tour on
January 10th, 2012, CDCR personnel provided these numbers orally to the CCST project team
5 U.S. GAO 11-893 Bureau of Prisons: Improved Evaluations and Increased Coordination Could Improve Cell Phone
Detection, September 2011
6	 U.S. GAO Report to Congressional Committees; “Bureau of Prisons – Improved Evaluations and Increased
Coordination Could Improve Cell Phone Detection”, September 2011
7	 U.S. Department of Commerce “Contraband Cell Phones In Prisons – Possible Wireless Technology Solutions”,
December 2010
8 Special Report, Office of the Inspector General, State of California, May 2009, “Inmate Cell Phone Use Endangers
Prison Security and Public Safety”

9

Contraband cell phones in the prisons can result in:
1.	 Inmates using these contraband cell phones to operate or control criminal activities
from inside the confinement of a prison.
2.	 Growing inmate demand for illegal smuggling of contraband material into the
prison.
3.	 An untraceable method for inmate communications with people inside and
outside the confinement area.
4.	 Inmates using contraband cell phones to circumvent the fee based pay phone
systems established to facilitate inmate calls. The CDCR indicates that this
circumvention has a negative financial impact to the provider operating the prison
pay phone system. In those states where a portion of the revenue from the use of
landlines is reinvested in prison rehabilitation programs, there is a financial loss
for the rehabilitation programs.
The risk of illegal activities being performed over these cell phones prompts the need for solutions
and intervention approaches to be identified and deployed. The value of contraband cell phones
smuggled into prisons can be up to $1000 per smuggled phone9 (this cost is in addition to the
external costs of phone purchase and service agreements with the carrier).

6.

Legal and Regulatory Context

In general, the current legal ramifications of smuggling, concealing and/or possessing cell phones
in prisons (state and federal) are minimal. Obviously, they are not enough of a deterrent to stop the
movement of or access to these technologies. They are, nonetheless, a start.
Federal Laws and Regulations
In August 2010, the Cell Phone Contraband Act of 2010 was passed and amended 18 U.S.C.
§ 1791 to prohibit an inmate of a federal prison from possessing, obtaining, or attempting to
obtain a cell phone.

	

California State Laws and Regulations
CA SB26 was passed and enacted in 2011 making possession of a cell phone by an existing
prisoner a misdemeanor. This bill would provide, with exceptions, that a person who possesses
with the intent to deliver, or delivers, to an inmate or ward in the custody of the department
any cellular telephone or other wireless communication device or any component thereof,
including, but not limited to, a subscriber identity module or memory storage device, is
guilty of a misdemeanor, punishable by imprisonment in the county jail not exceeding 6
months, a fine not to exceed $5,000 for each device, or both the fine and imprisonment. An
inmate found in possession of a wireless communication device will be subject to a time
credit denial or loss of up to 90 days. This law also provides “deemed consent” inside the
secure perimeter of a correctional facility to utilize technologies such as the Managed Access
Systems.
Governor of California Executive Order B-11-11: Contraband Cell Phones
This Executive Order, issued upon passage of SB26 directs CDCR to take additional steps
to control the proliferation of contraband cell phones, including preventing them from
penetrating beyond the prison’s secure walls and to immediately review and prepare an

9	 During a tour of the Solano State Prison and the California Medical Facility on January 10th, 2012 CCST Project Team
members learned this from discussions with prisoners.

10

analysis of any barriers to implement airport-style security screening at all points of entry to
California’s correctional institutions, and that this analysis be submitted to the Governor’s
Office by December 31, 2011.10 The order also required, among other things, that the CDCR
implement a system to intercept and block prisoners’ unauthorized cellular transmissions. The
CDCR is currently in a competitive procurement to install a permanent MAS in collaboration
with the Federal Communications Commission to meet this mandate consistent with federal
law at the majority of its correctional facilities.11 A copy of this report was provided to CCST
as we were finalizing this report (Appendix 6). From a review of the report it appears that
the cost of implementing full screening at each of the prison facilities as summarized in this
report is likely no more expensive than the estimated $1 million per prison estimated for
MAS installation.
Special Report: Inmate Cell Phone Use Endangers Prison Security and Public Safety – Office
of the Inspector General, State of California, May 2009 (D. Shaw, Inspector General). The
security issues related to contraband cell phones have been understood by the state for some
time. The Inspector General (Shaw), in his transmittal letter addressed to Secretary Cate,
CDCR, May 4, 200912 stated:
“…the Office of the Inspector General found that the possession of cell phones in prison
facilities by inmates has increased significantly during the past three years and poses a threat
to the safety and security of California’s prison staff, inmates, and the general public. We also
found that the growing number of cell phones in prison facilities is a direct indicator that the
methods used by the California Department of Corrections and Rehabilitation to interdict
their introduction or possession have mostly proven ineffective.”
To truly eradicate contraband cell phone usage the Office of the Inspector General recommended
that the Secretary of CDCR take the following actions. The recommendations are similar to CCST’s
current recommendations in this report (Appendix 7).

10	 CDCR PowerPoint Presentation to CCST Team by T. Vice, Cell Phone Interdiction Manager, CDCR, Jan. 5, 2012..
11	 Letter from Secretary Cate, CDCR to Ms. Robinson, Assistant Attorney General, US Department of Justice, October
31, 2011
12	 Special Report: Inmate Cell Phone Use Endangers Prison Security and Public Safety – Office of the Inspector General,
State of California, May 2009; Page -2

11

Office of Inspector General Recommendations
1.	 Continue efforts to seek legislative change to make the introduction or possession of cell
phones in all correctional facilities a criminal offense;
2.	 Collaborate with other state and federal correctional agencies to lobby the Federal
Communications Commission (FCC) for an exemption in using cell phone jamming
devices;
3.	 Request additional funds to purchase cell phone detection solutions and jamming
devices (if subsequently approved by the FCC);
4.	 Request resources and funds to conduct airport-style screening including metal and
canine detection, and when necessary, manual searches of persons entering California
prison facilities;
5.	 Restrict the size of all carrying cases being brought into the secure areas of prisons by
all persons including backpacks, briefcases, purses, ice chests, lunch boxes, file boxes,
etc., so that they may be x-rayed;
6.	 Require staff and visitors to place all personal items in see-through plastic containers;
7.	 Request additional resources and funds to increase detection activities similar to
“Operation Disconnect;”
8.	 Ensure all quarterly contract vendor packages be shipped directly to prisons and
correctional camps; and
9.	 Implement an anonymous cell phone smuggling reporting system for employees and
inmates.

7.

Overview of Contraband Cell Phone and Wireless Technology

The following section defines key terms and describes the operation of wireless communication
technologies. More detail is provides in Appendix 8. In addition, a technical evaluation was provided
by Sandia national Laboratories (Appendix 9). We note that the latter also describes possible other
technologies that could be considered in a pilot program.
In this report, the term “cell phone” refers to a radio-telephonic instrument used to make telephone
calls, send and receive text (SMS and MMS) messages, or send and receive data using licensed radio
spectrum. The term “contraband cell phone” is used to denote those cell phones in the unauthorized
possession of inmates within prisons.
Cell phones and devices can be used in many different ways. While the original intent was longerrange wireless communications, current advances in technology have increased the computing power
of a cell phone so substantially that new and emerging uses are being discovered every day. These
advances in technology have essentially resulted in a computer that can fit in a pocket. Today’s cell
phones are more capable than computers were just a few years ago. In addition, computer operating
systems extend usefulness of the cell phone to a full computing environment. It is expected that
this evolution of technology will continue at the same or faster rate resulting in an ever-increasing
expansion of the functions of cell phones.
Wireless Communications
Cellular phones are now commonplace for long-range wireless communications, via voice, text
message or data. The cell phone has become a ubiquitous assistant that is attached to nearly every
one of us during our daily routines. More and more often, the cell phone is becoming the only phone
for many people. The estimated penetration rate of cell phone volume versus population in the U.S.,

12

for example is in excess of 100%,13 and is even greater in many other countries14.
With the increasing capability of the cellular phone serving as a hand held computer, numerous
additional communications methods are being integrated into the device at a rapid rate. Included in
this expanding suite of capabilities are Wi-Fi and Bluetooth.
•	 Wi-Fi is the most common wireless local area network (WLAN) technology used for
wirelessly connecting computers and devices to one another.
•	 Bluetooth is a form of a wireless, short-range, personal area network (PAN) that is used to
connect devices together in close proximity, such as cell phones and headsets. Bluetooth
is a public domain wireless standard under governance of the Bluetooth Special Interest
Group (SIG).
These two capabilities alone enable the potential use of cellular phones for short-range
communications within the prison, e.g., between prisoner cells or between prison cellblocks.
Unlike the more traditional method of cellular phone communications, which rely on an
infrastructure network with towers and carriers, short-range communications can be accomplished
without fixed or existing infrastructure for operation. This short-range communications capability
could result in the ability for an inmate to call other inmates in close proximity and send data files
within range (up to hundreds of yards).
Smart Phones and Pocket Computers
Cell phones with multiple functions (including internet access) are referred to as “smart phones”.
Most modern cell phones have an array of embedded sensors and tools that can be used
independently of any cellular network. At a minimum, virtually any new smart cell phone now
has a keyboard, a camera and a flash memory card, such as microSD. Use of these features allows
inmates to provide instructions, in the form of written text and/or imagery that can be stored onto a
microSD memory card, the size of a fingernail. The memory card can then be easily moved around
a cellblock, or transferred to somebody on the outside, providing a delayed communications
channel independent of the cellular network.

8.

Stopping Use of Illicit Cell Phone Use in Prisons

Finding Phones at Entry Points
A primary response to the problem of contraband cell phones in prisons should be to more thoroughly
inspect all personnel entering and leaving the prisons, the confinement area, and all accessible
spaces, as well as the prisoners themselves. Installation and operation of airport-like screening points
would help ensure that personnel and visitors were not carrying in or out contraband items including
cell phones. Even manual searches would likely capture at least some potential contraband or deter
its entry. In some cases cell phone-sniffing dogs have been used to successfully screen incoming
vehicles and packages for contraband cell phones.15 Thorough screening at California State Prisons
(similar to screening at federal prisons, addressed later in this report) should be both an expected and
reasonable approach for California to implement. However, from the January 2012 CDCR briefing
and team member visits to prisons, the CCST Project Team learned that ‘airport’ level screening of
CDCR personnel and, in some cases even visitors, is limited or nonexistent. CDCR personnel were
observed carrying duffle bags and soft-sided ice chests in and out of the prison without thorough
screening.16 The fact that metal detectors or more rigorous manual searches are not routinely and
13
14
15
16	

http://ctia.org/media/industry_info/index.cfm/AID/10323)
http://www.parl.gc.ca/content/LOP/ResearchPublications/prb0826-e.htm#penetration
http://www.nj.com/news/index.ssf/2011/12/cell_phone-sniffing_dogs_used.html
CCST visit to Folsom State Prison in March 2012 did include metal detector screening of people but all possessions

13

rigorously implemented as a first line of defense at all California correctional facilities was a surprise
and concern to the CCST Project Team.
The CCST Project Team recommends that thorough screening of all personnel, items, and vehicles
be implemented consistent with the Federal Bureau of Prisons protocol (Appendix 2) and the 2009
recommendations of the California Inspector General (Appendix 9).
Identifying/Tracking Phone Use
Numerous technical methods exist for identifying a cell phone via the radio signal emitted by the
phone. Detection systems to identify this radio frequency signal vary in cost and complexity from
simple hand held devices to highly sophisticated systems capable of detecting both the use and the
location of the cell phone. These systems still require human engagement to assess detector outputs
and inspect the confinement area for the contraband phone. It should be noted that any method
requiring prison correctional officers to actively participate would likely arouse the suspicion of
the inmates. As a result, it is expected that when correctional officers begin inspecting an area of
the prison, prisoners would turn off contraband cell phones, therefore nullifying the efficacy of
the detection system. The limitations of this search approach calls for alternatives or companion
approaches for eradication of contraband cell phones use. Because of the difficulty in physically
finding the cell phones, the idea of automatically rendering contraband cell phones inoperable is
attractive to prison control organizations. This promise of an “automated” mitigation system has
sparked interest in the MAS installations in prisons; however, the CCST Project Team only found
evidence of one such system installed at a single prison in Mississippi and understand that this
system is not yet fully operational.
The CCST Project Team recommends that potentially useful technology approaches be explored
in confined prison areas, and that cell phone carriers be engaged to explore options of denying
connections for ‘unregistered’ cell phones within prison locations using the carriers’ technology. In
this latter case, identity of illegal cellular phones could be obtained via a benchmarking technology
and the carrier could then deny cellular connection to the specific unregistered devices. Engaging
the carriers would likely require either a legal requirement to participate or an income incentive via
fee for participation. With the recent agreement of cell phone carriers with the federal government
to disable services on stolen cell phones, this approach should be explored17.
Explore Prison Specific Jamming Approvals
The Federal Communications Act of 1934 prohibits the use of jamming technologies. However, as
the concern about contraband cell phones in prisons expands, there is growing interest in seeking
exception to this law to allow jamming within the prison environment. South Carolina prison officials
received FCC approval to test jamming technology that intercepts and terminates cell phone calls.
In one test, South Carolina officials reported that the technology was very effective at jamming cell
signals without interfering with cell signals in areas adjacent to the facility. However, the approval to
test was for a limited time and the FCC has not granted approval to implement the use of jamming
technology.18 With the growing national concern regarding use of contraband cell phones both as
a localized risk and a national security risk, there is renewed interested in seeking prison specific

that didn’t pass successfully through the metal screener (purses, coats, belts, shoes) were subsequently carried into
the prison without any search or screening.
17 Wireless carriers will permanently disable stolen phones, http://blog.sfgate.com/pender/2012/04/10/wirelesscarriers-will-permanently-disable-stolen-phones/
18	 Special Report, Office of Inspector General “Inmate Cellphone Use Endangers Prison Security and Public Safety”,
May 2009

14

approval for use of jamming technologies.19 This approach would take into consideration the need to
not hinder legitimate communications for administration, guards and others within the confinement
areas.
The CCST Project Team recommends that California (via legislative and executive branch efforts)
work in coordination with other states and California’s federal legislators to seek prison specific
exceptions to the Federal Communications Commission (FCC) anti jamming regulations. If such
exceptions are provided by the FCC the jamming technology should be tested in one or more pilot
projects at California State Prison facilities before implementation.

9.

What is Happening Nationally and in Other States?

Federal
The Federal Bureau of Prisons (FBOP) has adopted strict procedures requiring all personnel and
materials entering the prisons to be screened by metal detectors without exception. This strict
approach to screening all personnel has been implemented to help interdict contraband prior to its
entry into the confinement area of their institutions and is reportedly effective. (See Appendix 2 for
full policy.) 	
The Federal Bureau Of Prisons has not yet implemented MAS in their prisons. In September 2011,
the U.S. Government Accounting Office (GAO) issued a report20 on Contraband Cell Phone use in
Federal Bureau of Prisons institutions noting the size of the issue and recommending that the FBOP
should coordinate and share information with the states. Several states were called out (Alabama,
California, Florida, Maryland, Mississippi, New York, New Jersey, South Carolina and Texas, as active
in the arena of contraband cell phone mitigation studies. The GAO report reinforces that the cell
phone issue is a problem and that no one-technology solution can fully address it; the report notes
that a combination of detection, managed access and inspection should be considered.
States
The state of Mississippi is the only state known to have a MAS deployed. It has been installed at only
one prison, Parchman Prison. This MAS implementation was started in July 2010 and is still not fully
operational as of November 2011.21 The reasons for this are operational but not provided in detail
here at the request of the Parchman Prison administration.
South Carolina is preparing to start a pilot for MAS, Georgia has an RFQ out for MAS and Texas is
preparing to issue and RFQ for MAS. Both Georgia and Texas are using the California CDCR IFB
as templates for their bid requests. The information availability of correctional facility mitigation
techniques in foreign countries is not readily available for public review so the study team was
unable to assess if or how well MAS might be working outside the U.S.

10.

Review of Managed Access System (MAS) Technology

What is Managed Access?
The Managed Access System (MAS) refers to a standard cell phone network system used in a defined
close quarter geographic area such as a campus, military base or a prison. The theory behind MAS
is to allow authorized cell phones to connect to the standard carrier (e.g. AT&T, Sprint, T-Mobile,
19 New Jersey interest (Assembly Resolution 30 (Coughlin), 2011-2012 Legislative Session
20 http://www.gao.gov/products/GAO-11-893
21 Call with Parchman Prison – Team member Diamond.

15

Verizon) networks, while preventing unauthorized cell phones from connecting to the carrier
networks. A well-designed and implemented MAS would function as a system to detect and preclude
the operation of cell phones not authorized in the MAS approved database (Figure 1).
As depicted in Figure 1, the sequence of operational events follows:
1.	 Within a defined area, the MAS detects a cell phone attempting to connect to its
service provider’s base station – A
2.	 The MAS decodes the call information to determine the calling cell phone identity.
3.	 The MAS then compares the decoded cell phone identity to a database to determine
if this device is authorized for use within the MAS umbrella of operations.
4.	 If the cell phone is authorized, the call is allowed to continue uninterrupted by
the MAS - B
5.	 If the cell phone is not authorized, the MAS prevents the cell phone from connecting
to the carrier’s network. Once the MAS has taken control of the cell phone call it
can send a pre-designated message to the cell phone stating it is unauthorized for
use, or any other message the MAS owner/operator chooses - C
This sequence of events is identical to that used by commercial cell phone providers to process
calls from cell phones, except for the interdiction and return message for unauthorized calls. All cell
phones have to go through an authorization process with the service provider’s network database in
order for the call request to be processed.

Commercial
Carrier
(e.g. AT&T, Sprint,
T-Mobile, Verizon)

(B)

(B)

(A)

Authorized User

(A
)
Managed Access
System (MAS)

, (C

)

Unauthorized User

Prison or other Controlled Facility
Figure 1. MAS would function as a system to detect and preclude the operation of cell phones not
authorized in the MAS approved database

16

The physical equipment used to develop and operate a MAS is similar to that used by commercial cell
phone providers, though on a much smaller scale. Both a MAS and a cell phone provider network
are comprised of base station controllers, antenna arrays, interconnect cabling and computers for
management and information gathering.
Technical Feasibility of Managed Access Systems
The MAS is essentially a modified implementation of existing cell phone technology. If properly
designed and implemented it should be able to block all unauthorized calls within their radio
envelope and receiver signal identification capability. However, MAS can only block calls from cell
phones using compatible broadcast technologies. For example, if a service provider implemented
a new service, such as LTE (Long Term Evolution, referred to as LTE and marketed as 4G LTE, is a
standard for wireless communication of high-speed data for mobile phones and data terminals) the
MAS would not be able to recognize or block phones using the new service. Though the CDCR IFB
indicates that it would give the MAS vendor 1-year from commercial availability to incorporate new
cell phone technologies into the system, the IFB does not appear to provide a triggering mechanism
for the 1-year counter, nor a penalty for failing to do so (or even a reporting obligation). This leaves
open the important question of what would be the trigger. Also, it is important to note that as new
technologies develop there will be a time lag to identify them and to respond with an upgrade in the
MAS ability to detect them. The IFB trigger is also not clear with regard to upgrading or modifying
the system to address the evolving technologies.
Managed Access System Vendors and Systems
Data regarding commercially available MAS is scarce. This scarcity can be attributed to the infancy of
the MAS marketplace and the early stage of product development. The CCST Project Team identified
only two vendors 22of sufficient size to attempt to develop and implement the MAS for the California
State Prison system. There are other vendors of technologies that might be configured for the MAS
but they were not considered to have sufficient size or qualifications to be viable enough to include
in this report. In addition to these two vendors there are numerous resellers that buy products or
services from these vendors to configure and resell for different uses or applications. Shawntec, for
example, is a reseller who buys equipment from one of the identified vendors. Shawntec is also
the company that provided a “pilot test” of a MAS for the CDCR at the Solano State Prison and the
California Medical Facility (two adjacent facilities).
It is key to note that currently MAS systems are not custom designed for use in correctional
environments; instead, they are miniature cell phone networks similar to those used by Wireless
Service Providers such as AT&T, Verizon, T- Mobile etc., with the potential to be adapted to fit small
geographic coverage areas such as a correctional facility. 23 The systems discussed below are either
small cell mobile wireless networks or cell phone test equipment configured to “act” as a managed
access system.
One of the vendors that the CCST Project Team talked with offers an intelligent network access
controller. This company is a systems integrator using sub-assemblies from a variety of suppliers
to build their MAS. The specific MAS component is a software and hardware system allowing the
transport of several different cell phone protocols (e.g., GSM, CDMA, LTE) to be carried in one
“backhaul packet” connecting to the core of the telephone company’s network. This system is a
small-scale cell phone network that operates exactly as a service provider network such as AT&T or
T-Mobile. The system does not have any automated means to determine RF envelope dispersal for
interference management.
22 Tecore Corporation and DRT Corporation, a wholly owned subsidiary of The Boeing Corporation,
23 RF envelope and interference management are discussed in Appendix 3

17

The only MAS system currently implemented in a U.S. correctional facility is the Parchman Prison
in Mississippi. This system has been in operation at Parchman Prison since July 2010. According to
the Mississippi Department of Corrections, this MAS is still a pilot operation and is not fully deployed
due to operational issues. Roll out of the system to other Mississippi prisons is on hold until these
issues are worked out satisfactorily.24 The equipment used at Parchman Prison is not the equipment
tested in California at a CDCR facility.
Another vendor uses test equipment that emulates the base stations and phones as well as the
operational radio network controller function. This is the equipment that was used by the CDCR in
its pilot test of MAS capability at Solano State Prison and the California Medical Facility.25 In the
tests at these two prisons, the subsystems described above were configured to be a MAS capable
system. The equipment used did not have any automated means to determine RF envelope dispersal
for interference management (i.e., there is no way to determine if the radio signal it generates could
or is causing interference outside the confinement area of the prison). The CCST Project Team did
not find any evidence that this combination of subsystems was implemented as a fully operational
MAS. The CCST Project Team reviewed a copy of the summary report of the CDCR pilot-testing
program. Notable in the CDCR summary report was a lack of description of the equipment used or
any of the operational issues encountered during the test implementation or operation. Members of
the CCST Project Team discussed the test with a CDCR representative who worked with the vendor.
From the discussion, the CCST Project Team learned that the test was very rudimentary and would,
at best, constitute a proof of concept, not an acceptable operational pilot test. The CCST Project
Team understands that the tested MAS did provide a cell phone blocking function, but it was not
automated. Consequently the MAS experiment was very manpower intensive and never operated in
a standalone mode as required by the CDCR IFB.26
Risk and Challenges of the MAS Approach
Because of the paucity of system vendors, the lack of the ability to monitor interference outside of
the subscribed area, and the lack of large-scale operational application of technologies used for
MAS, there is no template of implementation techniques to model or follow for MAS. If the CDCR
proceeds with the IFB as currently written, it would be important to note that each correctional
institution installation will be a new learning experience, and each caveat would be discovered as
it is installed. Although similar problems are likely to arise at each installation, solutions for each
individual prison are likely going to vary significantly depending on a complex host of local factors.
The proposed MAS systems lack the finite systematic radio power level control capability necessary
to prevent interference in real time. This means the only mechanism for interference mitigation
would be by exception. For instance, when someone’s cell phone service outside the prison is
affected by interference, they would need to report it, and the cause could then be detected and
corrected. The proposed MAS approach also lacks the capability to be simply modified for new
cell phone communications technologies. Each and every upgrade of the MAS systems will be
tantamount to a complete new installation. This, predictably, would be disruptive and could lead to
long periods of inferior performance.
Still, the concept of utilizing MAS to control cell phone use in prisons is an appealing concept.
Some of the many challenges that need to be addressed to have a fully functional and effective
system include:

24	 This information was collected in telephone contact with Mississippi corrections management in November 2011
by CCST and California Senate Office of Research individuals.
25 Information on this pilot provided by CDCR.
26 As conveyed by CDCR personnel to the CCST Project Team.

18

Frequency Allocation
The MAS uses a licensed radio spectrum owned by the service providers, (e.g. AT&T or Verizon),
and therefore it is illegal to “radiate” in these frequencies without prior agreement with the spectrum
owners. The spectrum owners are under no obligation to allow free use of this radio space to the
prisons or to agree to any for fee use for deployment of the MAS. The CDCR has stated they will lease
the spectrum from the spectrum owners and through re-lease agreements; the MAS operator will
utilize the spectrum. While this approach could ensure the spectrum is available for MAS it will not
absolve the CDCR from interference liability, and may in fact make CDCR liable for interference.
This approach increases the requirement for tight control of the RF envelope dispersal.
FCC Regulations
Relatedly, the lack of an FCC requirement for spectrum license owners (e.g. Verizon, AT&T, etc.) to
allow for use of their spectrum within the prison area to be used for MAS is a key issue. Without
this requirement, the state is forced to negotiate with each carrier on its own to enable the MAS
operation. To date, the FCC has not created a policy for corrections departments at any level to
acquire the permission from the spectrum owners for ways to control the calls (e.g. MAS or jamming).
A coordinated effort of several states to petition the FCC to modify existing spectrum owners’
agreements to require they provide unobstructed use of their spectrum within the geospatial
confines of corrections facilities would be an important modification of regulations. If this effort
is undertaken, the discussions could also include the possibility of using jamming technologies in
some conditions.
Installation
Since the MAS is a cell phone system with antennas and interconnect cabling and support computers
it will need to be installed in highly secure areas away from inmate access to prevent tampering
or destruction. The existing cabling systems in prisons will not support the RF signaling being
carried to and from the antenna arrays and the transmitter receiver systems. All required MAS
infrastructure will need to be newly installed.
RF Dispersion
Since the MAS radiates RF energy capable of interfering with any cell phone using the same frequencies,
absolute control of the RF envelope is mandatory. The RF envelope is the actual physical distance
and pattern that the RF energy travels and the dispersal power of the radiated energy. In simple terms,
this means the MAS system’s radiated energy cannot be allowed to propagate beyond the specific
physical confines of the prison area. This RF envelope will change characteristics with temperature
and humidity, wind, tree growth and building construction or modification. The complexity and
negative effects will vary by prison location. For example, a prison in a highly rural area may be
far enough away from roads or structures that RF leakage would be an issue only when someone
entered into the prison MAS “zone”. However, if the prison is in or near a populated area, this RF
leakage could be highly disruptive to cell phone usage by the non-prison population. Among other
things, this disruption could greatly reduce the capability of public safety professionals to serve the
community’s needs or the general public’s ability to access a 911 operator.
The control of the RF envelope is the combination of signal transmission power and antenna output
lobe dispersal management. Ideally, the MAS would have a dynamic signal power and direction
control system capable of changing the output signal based upon the immediate environmental
circumstances. This dynamic system would be comprised of what are called active feedback sensors
to measure the specific energy emitted by the MAS antenna. These sensors would then provide
real time feedback to either the MAS to automatically change power of energy emitted or more
realistically notify the MAS operator of a need to correct any RF leakage outside the target coverage

19

area. The construction of each prison and its location in the population demographic will mandate
that the MAS implementation technique and RF envelope management be employed.

11.

Limitations of Managed Access System Technology

The basic capability of the proposed MAS equipment to recognize cell phone usage in all the current

bands and modulation techniques, e.g., CDMA, UMTS, GSM, and block or interdict the call is
available today. The capability to detect and interdict 4G signals such as Long Term Evolution (LTE),
however, is not currently available. It is expected that a MAS vendor would need to implement LTE
radio interdiction prior to implementation of the MAS. This capability is fundamental to cell phone
network system operation and should not be technologically challenging.
However, in the context of the current CDCR IFB and the requirements for RF envelope control for
interference mitigation coupled with highly automated operation, neither of these above approaches
would be classified as effective. Current MAS technologies require significant human intervention
and operational action due to a complete lack of automated feedback of operational performance.
The MAS systems of today cannot distinguish the location of a cell phone for blocking. If the RF
envelope is incorrectly deployed, all cell phones in its range will be blocked unless specifically
identified as an allowed user on the access control list. The IFB calls for all 911 calls to be allowed
to pass. It is important that all emergency calls be routed to the E911 Emergency Response Center
and not to another location coded into the MAS call routing system.
Circumventing the MAS
The idea of circumventing the MAS is more of a use case question than a technological question.
If the MAS is capable of identifying that a cell phone is in use it can interdict and block the call.
However, as different applications of the ‘cell phone’ or Wi-Fi connectivity are developed, it is likely
that the MAS could be bypassed.
Texting
Texting is a simple means to send a brief “note” from one cell phone user to another, analogous to
a Post-it note. The sender types the message and then pushes the send button. The message is sent
immediately to their service provider, who stores it for future delivery to the recipient. This is very
different from a voice phone call, in which the service provider must actually locate and connect
to the targeted user before the call is processed. Text messages take less than 1 second to send; in
comparison, it takes up to 5 seconds to establish a connection for a voice call.
The time difference is important because the IFB for the MAS requires that the system detect and
attempt to block unauthorized calls within 60 seconds; this could result in the response time being
the full 60 seconds. Inmates will figure out that a text message can be sent in seconds and does not
require the cell phone to “dial a phone number” as with a voice call. A text message can even be
prewritten offline, and the cell phone activated and the message sent in well under the 60 second
requirement of the IFB for the MAS to detect the attempt and block its completion. Because texts can
be sent very quickly, the efficacy of the MAS in blocking these has not been proven. The receiving
cell phone of a text can even be turned off when the text is sent because the network will store and
forward the text message when the receiver’s phone is turned on.
Incoming Calls
One more area of concern is the MAS efficacy in blocking incoming calls to contraband cell phones,
especially for text messages. It is not known what would happen if the MAS attempts to block a
service provider base station; in this case, the contraband cell phone is not attempting to place a

20

call. It is hypothesized that incoming calls would also be processed much faster than a call out and
thus may circumvent the 60 second window for the MAS to activate. This scenario has not been
tested.
Data Transmission via Flash Memory Card
Most cellular phones available today have the capability to read and write to small flash memory
cards. The most common flash memory used today is the microSD card, which is as small as a
thumbnail – microSD cards measure only 11mm x 15mm. (See Figure 2.) This small memory card
can hold as much as 64GB of data today, and will only increase in capacity in the future. By utilizing
flash memory cards, inmates could send text files or images both inside and outside of the prison
walls, simply by saving files onto the card and physically distributing the small device.

Figure 2: Flash Memory microSD
Card Image from http://support.jvc.com/consumer/products/glossary.jsp?gId=337

12.

Can California Serve as a MAS Model?

The CDCR has stated the desire to be the model for effective contraband cell phone interdiction efforts
for the United States. Given the state of implementation nationwide, if installed and implemented, the
CDCR would be the test case for the first large scale MAS deployment. The CDCR has an aggressive
schedule for MAS deployment for 33 institutions in 36 months. The plan is to implement the first site
in Solano State Prison to gain “acceptance” before proceeding to phases 1 and 2, which effectively
split the 33 target institutions into 2 groups27. If contraband cell phone use interdiction is mandatory,
some form of cell phone MAS could be useful. However, the current MAS technology designs need
more testing to understand the rigors of a correctional institution environment.

27	 Invitation for Bid (IFB) was issued by the California Technology Agency on behalf of CDCR on July 7, 2011; IFB 11126805

21

Review of California Department of Corrections and Rehabilitation (CDCR) Pilot Program Findings
and Conclusion
Members of the CCST Project Team reviewed available CDCR documents about their MAS pilot effort
and discussed the test effort with the CDCR staff. The CCST Project Team concluded from available
information that the MAS test was more a proof of concept demonstration rather than a true pilot
MAS installation. The CCST Project Team also concluded that the proof of concept effort undertaken
by the CDCR was not robust enough to form the only basis for the technical content of the CDCR
IFB. The Project Team learned that in the case of the data showing “successful” call blockings, the
vendor supplied the cell phones; furthermore, only one cell phone of each service provider type (e.g.
AT&T, Verizon, etc.) was tested. The test lasted a total of 96 hours (4 days). This does not constitute
a suitable test period for a system with the complexity of the MAS that is proposed to be deployed
across facilities of different designs with varying geographical and weather parameters.
Missing Financial Documentation and Efficacy Requirements in the IFB
The CDCR IFB is written so as to require the winning bidder to operate, maintain and pay all costs
associated with the MAS. The MAS is to be funded from revenues generated by the Inmate and
Wards Telephone System (IWTS) operation. This system is provided to incarcerated persons by the
CDCR but operated and maintained by a third party vendor. The IFB for the MAS is a portion of a
greater IFB including the IWTS and MAS systems. The IFB calls for a portion of the revenues from
the IWTS operation to be used to implement, operate, and maintain the MAS with no cost to or use
of CDCR resources. The IFB calls for the winning IWTS bidder to pay the CDCR $800,000 annually
for 6 years with a CDCR option to extend the contract for 4 additional years. Beyond training that
some CDCR personnel will receive to enable use of the MAS database and management of the
proposed trouble ticketing system, full responsibility for the installation and operations of the MAS
belongs to the winning bidder. It was not clear from the documents reviewed how the $800,000
payment amount was calculated and what it is based upon; thus it is not clear if this is appropriate
or what amount of overall revenue will be generated by the ITWS. One significant concern of this
proposed arrangement is the issue of how to measure success at the corrections facilities included in
the IFB. There is no mechanism in the IFB requirements that provide for third party (or even CDCR)
evaluation to determine if the system is working or to adequately adapt the system to changing
technologies or other circumstances.
Societal Considerations
The societal considerations for the MAS in corrections facilities are broad and varied. In CCST’s
initial review of the July 7, 2011 IFB from CDCR, there was noted concern that information collected
during the process of blocking contraband cell phone calls could be covered by a variety of privacy
laws. In subsequent IFB revisions, the categories of data collected during a blocking activity by MAS
have been significantly limited. These changes eliminate CCST’s concern that collected data was
potentially a privacy issue.
During CCST’s visit to two prisons (Solano State Prison and California Medical Facility) in January
2012, we had the opportunity to interview inmates, gathering a unique perspective on the contraband
cell phone issue. The opinion expressed by some inmates during those visits was that cell phones
used by prisoners allowed unfettered contact to family and loved ones otherwise unavailable.
The question, “If cell phones were provided as part of the IWTS, and knowing that the calls were
recorded, would this deter cell phone use?” was answered with a “no”; the inmates indicated that
they were used to their calls being recorded when using the IWTS. There was also acknowledgment
by the prisoners that a percentage – small by the inmates’ estimation – of cell phone calls are used
for illicit and illegal activity. It was noted by the CCST Project Team that access to cell phones (even
if monitored by CDCR via computers with screening software) offers to many inmates an ongoing

22

connection to family and friends, as well as entertainment on smart phones (such as games, videos
and ESPN sports games). Consideration could be given to piloting a method to screen contraband
cell phone calls (rather than blocking) to better understand the impacts that the phones have on
prisoner recidivism and overall prison temperament.

13.

Benefits of a Robust Pilot Project

With regard to the MAS, CCST’s overall findings are that the MAS technology of today is not yet
mature enough for large-scale deployments such as the 33 CDCR prisons target. In addition, the
CDCR has not actually identified the size of the problem or a mechanism to determine the efficacy of
MAS deployment to mitigate contraband cell phone usage. CCST recommends a delay in deployment
of the CDCR MAS for a period of 18 months to enable a robust MAS Pilot Network installation and
operation that could be designed to address the following set of issues:
Establishment of a baseline and development of measures of efficacy:
No specific measurable target of efficacy for the MAS has been identified in the IFB with regards
to the volume of cell phone usage before and blocked calls after the MAS deployment. The pilot
network installation needs to include a means for determining the “size of the problem on a per
institution basis.”
An accurate measurement of the problem needs to be determined in advance of implementation of
the MAS to establish a baseline “size of the problem” for each institution. The CDCR has no baseline
of the actual volume of calls originating from contraband cell phones over an extended period of
time. The only metrics existing are the number of cell phones confiscated and a measurement of
calls attempted during the 11-day test at Solano State Prison. An accurate and current baseline is
important to determine the efficacy of the MAS.
To obtain this baseline measurement, cell phone RF detection equipment would be placed throughout
the target facility and configured to achieve 100% coverage, for 30 days immediately prior to the
MAS installation. The detection equipment would need to capture the cell phone identifier28 of
the device placing the call so authorized calls would be filtered out prior to the MAS target metric
establishment. The exact settings of this capture equipment would need to be studied since the
potential for calls placed in very close proximity to, but outside the confinement area would need to
be excluded. Also, close coordination with the local wireless service providers would be necessary.
Development of a template for implementing the MAS in a correctional institution:
There is no proven template for implementing the MAS in the demanding environment of a
correctional institution. The pilot network installation will result in creation of this template. The
MAS as a unique technology solution to blocking usage of contraband cell phones in prisons has yet
to prove itself as successful or unsuccessful.
With only one installation in a uniquely rural prison (Parchman Prison in Mississippi) started in
July 2010 and still unproven, the jury is still out on the ability of this approach to be applicable to
the prison environment. It is clear that MAS technology would be able to block cell phone usage
in a controlled environment. It is not yet clear that this technology can be effectively installed and
operated in a prison facility. Also of concern is whether the unproven system could be effectively
managed by the CDCR and the successful IWTS/MAS vendor. A true pilot MAS system needs to
be tested before being adopted by the CDCR. An effective pilot MAS should be tested for 9 to 12

28 It is unclear whether this is legal or not. The CCST Project Team received various answers from vendors, law
enforcement and lawyers.

23

months. This pilot implementation needs to be “live” and block contraband cell phone usage as
intended in the IFB. This pilot could become the “template” for subsequent MAS implementations
in the CDCR and potentially all U.S. state and federal correctional institutions deemed appropriate
for MAS. This is not a trivial task.
Establishment of a third party oversight and verification of effectiveness:
No ongoing third party oversight or review of the MAS operation and conformance to wireless
operations standards is addressed in the IFB. This issue could be addressed in a pilot with a mechanism
for third party oversight being developed during network installation and operation.
This would be a detail-oriented process to ensure things such as the MAS being in compliance with
the FCC regulations. This would also allow for refinement of agreements with local mobile wireless
operators and identification of a third party to assure efficacy.
Development of a process to ensure the MAS evolves to address emerging technologies:
There is no mechanism to measure vendor compliance to emerging wireless technology and
deployment modernization techniques. These mechanisms will be devised and the process
documented during the pilot network installation and operation.
This is a longer-term process of identification of new wireless technology inclusion into the MAS by
the operator and verification of operation and efficacy by the CDCR.
Review of societal issues related to cell phone use by prisoners:
A pilot project would afford the opportunity to consider if there are some positive aspects of cell
phones in the prison environment (perhaps in minimum security facilities) such as staying connected
to family and friends and to relieve boredom (e.g. watching ESPN). The pilot would also provide a
chance to evaluate the impact of eliminating cell phone access on the overall state of mind and
behaviors of inmates, both individually and throughout a facility. This is not a technological or
operational issue. This concerns the state of mind and behaviors of inmates. The pilot project could
experiment with options such as allowing some cell phones that are provided with the understanding
they would be monitored and recorded similar to the IWTS.

14.

Third Party Consortium Oversight

The issue of contraband cell phones in prisons is very complex. Entrance detection, correctional
personnel education, inspection and MAS combined has the potential to be effective if the MAS
system is tested and modified to be effective in the prison environment. A thorough study of the
MAS combined and with the communities of interest has the potential to develop into a successful
mitigation method.
A consortium of participants should be identified and tasked to develop the pilot parameters and
specifications, and to oversee installations, operation and evaluation. This same consortium would
oversee and obtain the baseline measures needed to determine the efficacy of the pilot and to help
determine return on investment (ROI) with regard to the MAS interdiction approach. Members of
a consortium could be drawn from independent experts, the CDCR, California Senate Office of
Research (SOR), the California Technology Agency (CTA), the University of California (possibly the
UC Center for Information Technology Research in the Interest of Society (CITRIS) and UC California
Institute for Telecommunications and Information Technology (CalIT2 ), the California State University
(CSU) system, relevant local mobile wireless service providers, the Cellular Technology Industry
Association (CTIA), the Federal Bureau of Prisons (BOP), the Federal Communications Commission
(FCC), and the American Correctional Association.

24

This consortium could design and implement one or more pilot MAS efforts and could study the
technological nuances found in correctional institutions that might impair effective installation of the
MAS, the impacts on prisoner attitudes and behavior to a dramatic loss of outside world contact, the
long term issues of effective installation, maintenance, and operation, and the legal implications on
inmate privacy. The consortium would be able to expand upon this initial list.
A successful pilot approach could become the template for regulatory, societal, legal and procedural
process and actions for use of MAS on a national scale.
The consortium could also take an in-depth look at alternative options for mitigating contraband
cell phones such as the screening technologies, use of microcells, and exploration with cell phone
carriers for their engagement in denying services to unregistered cellular phones seeking connection
from within prison confinement areas.

25

Appendix 1: Project Team Members
The CCST Contraband Cell Phones in Prison Project is fortunate to have an outstanding set of
participants led by Charles Harper.
Chair
Charles Harper, Senior Vice President, Strategy and Systems Innovation Group, Semtech*
Technical Experts
Patrick Diamond, Consultant & Technical Project Study Team Lead
David Goldstein, Sr. Systems Engineer, The Charles Stark Draper Laboratory, Inc.
Brian W. Carver, Assistant Professor, University of California, Berkeley
NASA Ames Technical Experts
S. Pete Worden, Director, NASA Ames Research Center**
Don Beddell, Network Engineer
Bobby Cates, External Interface Network Engineer
Deb Feng, Deputy Center Director (acting)
Ray Gilstrap, Network Engineer, Information Technology Directorate
William Hunt, RF/IT Technician
William Notley, ARC RF Spectrum Manager
James Williams, IT Director and ARC Chief Technology Officer
CCST
Susan Hackwood, Executive Director
Lora Lee Martin, CCST Director, Sacramento Office
* CCST Board Member
** CCST Council Member

26

Appendix 2: CCST Letter to Senators Identifying IFB Issues of Concern (October

29, 2011)

27

28

29

30

31

Appendix 3: Letter from Senators to Matthew Cate, Secretary, California
Department of Corrections and Rehabilitation (CDCR) Conveying Issues from
CCST’s October 2011 Letter

32

33

Appendix 4: Preliminary List of Issues Identified with Status Update
Summary of Issues identified by the CCST Project Team in IFB#11-126805 as issued by the California
Technology Agency on behalf of CDCR (July 7, 2011). These issues were provided to State Senators
in a Letter dated October 27, 2011, and subsequently forwarded by the Senators to Secretary Cate
of CDCR (November 6, 2011)

Issue #

Issue of Concern

Summary

CDCR Action Taken

Status

Item of Direct Risk to the State
1

Require Agreement
It is a violation of Federal law to
with Spectrum Owners use licensed spectrum without
permission of the registered
owner (e.g. a vendor like
Verizon).

CDCR modified IFB to take
responsibility for licensed
spectrum usage agreement

Mitigated in the
IFB but still a
task to be done.

2

Data Ownership &
Confidentiality

If the data resident in the MAS
system is compromised it could
lead to personal safety risks
and privacy of communications
issues.

CDCR removed from the IFB Mitigated in the
the requirement to capture
revised IFB
and store information with a
privacy component.

3

Potential Liability
exposure with
expansion of purpose
from blocking to
snooping

This requirement in the IFB could CDCR removed from the IFB Mitigated in the
lead to a violation of prisoners’
the requirement to “snoop”
revised IFB
rights to due process and
on calls.
attorney client privilege.

4

Security of MAS
If system is hacked, and data
information technology resident on system compromised,
technologies
it could lead to personal safety
and privacy issues.

CDCR removed from the IFB Mitigated in the
the requirement to capture
revised IFB
and store information with a
privacy component.

Items Affecting System Efficacy
5

Lack of 3 Party
verification of
effectiveness

IFB provides for bidder to be
No Change to IFB evident
responsible for testing and
reporting on the MAS System and
Carrier Signal Verification.

Open Issue- no
clearly identified
audit mechanism

6

Unreasonable
requirements for
future spectrum band
management.

Unrealistic technological
obligation on the MAS for future
proofing of technology as yet
undefined.

Open Issue

rd

34

No Change to IFB evident

Issue # Issue of Concern

Summary

CDCR Action Taken Status

7

Lack of mechanism to
ensure MAS provider
does not interfere with
authorized cell calls

MAS could interfere
with signals outside
of the perimeter of the
correctional facility with a
potential impact on public
safety and emergency
response.

No Change to IFB
evident

Open Issue

8

Lack of clearly defined
criteria

The IFB requires MAS be
fully deployed…. There are
no set criteria against which
this can be determined.

No Change to IFB
evident

Open Issue

9

Lack of attention
to work-around
technologies

No requirement for
MAS vendor to evolve
their system to capture
signal from work-around
technologies

No Change to IFB
evident

Open Issue

Items Affecting Practicality/Capability
10

11

12

Lack of Access to existing Winning bidder required to
No Change to IFB
wiring infrastructure
install new infrastructure and evident
excludes use of existing wiring;
could disqualify otherwise
capable bidder

Open Issue

Cost of the MAS vs. land
line revenue

No Change to IFB
evident No

Open Issue

Weight of IFB focused on The MAS requirement was
No Change to IFB
IIWTS not MAS
not fully integrated into the
evident
IFB but rather appears to be
appended on as afterthought.
Lack of precision in
requirements could lead to
failed implementation.

Open Issue

Appears to not be a remedy
for bidder if revenues from
the IWTS land line fails to
cover costs of MAS

35

Potentially
a facility
specific issue.

Financial
Issue/
exposure

Appendix 5: April 11, 2012 Letter from Senators to Secretary Cates, California
Department of Corrections and Rehabilitation (CDCR) Conveying Notice of
the Immanence of the
CCST report.

36

37

Appendix 6: An Analysis of Barriers to Implementing Airport-Style Security at
all Points of Entry to California’s Correctional Institutions, January 2012

38

39

40

41

42

43

44

Appendix 7: Federal Bureau of Prisons Electronic Search Protocol29
1.	 All staff will be required to clear a metal detection device prior to gaining access to the secure
confines of the institution. “Secure confines” for this purpose generally means entering the
secured inner perimeter of the institution.
Electronic searches of all Bureau of Prisons staff will be conducted via walk-through or handheld metal detectors by designated staff member(s). No inmate visitors will be allowed to
remain in the area, or allowed to view screening procedures, when electronic searches of
staff are being conducted.
It is the responsibility of the employee to clear the metal detector by either passing all
items through the metal detector or by placing all items on an available x-ray machine for
screening. If the staff member is unable to determine the origin of the item causing the metal
detector activation, a designated supervisor will be consulted immediately to determine the
next appropriate step to clear or deny the employee for entry. An adequate private screening
area for staff will be made available for this purpose. Employees will be allowed to take any
items not able to clear the metal detector or x-ray machine to their vehicles, unless doing so
would jeopardize the safety, security, or good order to the institution. Existing limited secure
storage for cell phones and other personal items (not otherwise prohibited) will be provided
for staff that commute via public transportation.
Employees leaving the secure confines of the institution during their shifts are required to
clear metal detection upon re-entering the institution.
2.	 During the initial six weeks of implementation of these procedures, management agrees to
meet weekly, or at a mutually agreed upon time, with the Union President or designee to
review institution policies and procedural changes due to the implementation of electronic
searches.
3.	 Employees required to perform work in excess of their regularly scheduled hours will be
compensated in accordance with applicable laws, rules, and regulations.
4.	 Employees with a non-paid duty-free lunch break will be afforded their full 30 minutes lunch
break. Employees who leave the institution for lunch will be allowed a reasonable amount
of time to return to their post in the event of unusual and unforeseen delays in clearing the
metal detection screening process.
5.	 During the initial six weeks of the implementation of electronic searches, a supervisor
(excluding an employee serving in an acting capacity) or management official will be in the
search area assisting with screening.
6.	 After the initial six weeks, management will ensure a second staff member is available to
expedite the screening process during peak hours. A designated supervisor or management
official will be available via radio or telephone for consultation on any issue that may occur.
After the initial six-week observation period, staff will contact a designated supervisor to
address any concerns that may arise. Each Chief Executive Officer (CEO) will define peak
periods for staff entering their institution either by issuing a memorandum to all staff, or
posting the information by a method available to all staff, such as an electronic message
board in the front lobby.
7.	 A radiation exposure badge will be in the immediate search area of each x-ray machine.
Periodically these badges will be evaluated for exposure levels.
8.	 Staff required to utilize the x-ray/metal detectors will receive appropriate training prior to
29 Source: Federal Bureau of Prisons

45

being assigned to any post requiring the operation of these devices.
9.	 Staff members who have medical conditions that will not allow them to clear or pass
through electronic screening devices will be issued a pass by the Warden, upon receipt of
administratively acceptable medical documentation (e.g., medical certificate, a physician
issued medical ID card, etc.) indicating their medical condition and the extent of the
restriction(s) regarding their ability to clear electronic screening. Management agrees to
abide by all appropriate privacy laws and will make adjustments to this requirement as
needed.
The medical pass does not exempt the employee and their property from clearing the
electronic screening but will be tailored to the employee’s specific medical issues.
10.	Safety-toed footwear will be in accordance with the Master Agreement. Eligible employees
will have the option of an equivalent composite safety-toed footwear during their next
issuance.
11.	Random pat searches of staff persons, random visual searches of staff belongings, and random
searches of staff vehicles are not permitted pursuant to these procedures.
12.	Staff remain subject to the same reasonable suspicion searches, detention, and arrest, as
provided in the Bureau policy on Searching, Detaining, or Arresting Visitors To Bureau
Grounds and Facilities.

46

Appendix 8:
1. What is Radio Frequency (RF) Communications - The Idea of Waves as
Energy
This section provides an overview of the physics of moving information or intelligence via a radio
wave generated by an electronic circuit.
What is a Radio Wave?
The best analogy is the waves that move across the surface of water. These waves are identical to
radio waves in the basic physics of motion as a result of some type of stimulus. Waves on water are
caused by a disturbance of the surface of the water. These waves are created when the surface of
the water is perturbed in some way, for example a rock is dropped into the water. As the rock passes
through the surface the stimulus of this passing pushes water out its path. This pushing action creates
waves that emanate outwards from the point of entry. The size of wave is directly proportional to the
weight of the rock and the spacing between the waves is directly proportional to the speed of the
rock. The speed and weight of the rock are directly coupled physically so the waves move outward
carrying both the frequency and power this physical transfer of energy created. These waves move in
perfect symmetry in all directions simultaneously, until an obstacle is encountered. When a portion
of the wave encounters an obstacle the wave shape, size and speed are changed. Now there are
multiple waves traveling across the water’s surface, each correlated to the others in that they came
from the same source, but different because some of the wave has been disturbed. Radio waves do
the same thing in air.
The relationship between these slow moving physical waves in the water and high-speed invisible
radio waves is in the use of the terms “power” and “frequency”. The power of the wave is how high
it is above the non-disturbed water’s surface, and the frequency is how many waves pass the same
point in one second. In radio waves the power is the “electronic force” pushing the electrons into
the air and the frequency is how many times per second does a “new” wave start moving into the air.
Another thing water and radio waves have in common is the physical phenomenon of the distance
they travel. Once generated, undisturbed water waves can travel extreme distances, continually
getting smaller and smaller, thus losing “power” but maintaining the number of waves per second
passing any point (frequency). Radio waves do the same thing. And, when water based waves
encounter other water based waves at the point of intersection they interfere with each other’s power
and frequency. Radio waves do the same thing.
Overview of RF
Radio Frequency (RF) transmissions are emissions of radio waves that transmit information. These
emissions can be transmitted and received by antennas to allow for wireless communication.
Common types of RF transmissions are radio (AM/FM) signals, terrestrial television signals (overthe-air television) and wireless communications such as cellular phones, Wi-Fi (IEEE 802.11 based
wireless local area networks) and Bluetooth (personal area network technology). Frequencies are
identified using the measurement of Hertz (Hz). Hertz refers to the number of oscillations per second;
therefore a signal at the frequency of 300Hz would oscillate 300 times every second, and a signal at
the frequency of 2.4GHz would oscillate 2.4 million times every second.

47

RF Frequencies
Frequencies can be thought of as channels (such as television) or stations (such as radio). In fact, both
TV channels and radio stations correspond directly to a frequency being used. KTXL in Sacramento,
CA is channel 40. This channel assignment corresponds with the frequencies of 626-632MHz with
picture, audio and other signals being broadcast at specific frequencies in that range. California State
University, Sacramento (CSUS) radio station KXJZ is broadcasting at the frequency of 88.9MHz.
Many people are familiar with 2.4GHz, which is the operating frequency for many household
products such as Wi-Fi and Bluetooth. Terms such as 2.4GHz are commonly used to describe a
range of frequencies that are allocated to a common use. In this instance, 2.4GHz refers to the
range of frequencies between 2.4GHz and 2.5GHz that are allocated for Industrial, Scientific and
Measurement (ISM) purposes. The most important parameter of this band is that it is unlicensed,
meaning that anybody can operate in that frequency range, which is why you can own a 2.4GHz
router and operate it without an FCC license. Most bands, which are licensed, require authorization
from the FCC (within the U.S.; similar agencies exist in other countries worldwide) to operate
using those frequencies. Examples of commonly used licensed bands are 850MHz and 1900MHz
cellular frequency bands. Shown below are the International Telecommunications Union (ITU)
band allotments for RF spectrum. The Very High Frequency (VHF) frequency band is broken up to
provide an example of how the frequencies within a band are utilized. In this image only a few of
the selected uses are shown, many more exist within the band.

SHF

3000GHz (3 THz)

UHF

300GHz

VHF

30GHz

HF

3000MHz (3 GHz)

MF

300MHz

LF

30MHz

VLF

3000kHz (3MHz)

ULF

EHF

THF

Satellite Radio

2.4GHz ISM

2360MHz
2310MHz

Cellular (3G)

2483.5MHz
2400MHz

2155MHz
2110MHz

900MHz ISM

Cellular

Public Safety

Public Safety

Television

Gov’t Use

“Walkie-Talkie”

1990MHz
Cellular (PCS)
1930MHz
Cordless Phones
1920MHz
1910MHz
Cellular (PCS)
1850MHz
1755MHz
Cellular (3G)
1710MHz

928MHz
896MHz
851MHz
824MHz
806MHz

470MHz
450MHz

Assigned Use
(Selected Freq’s)

300MHz

Frequency

SLF

300kHz

ELF

30kHz

ITU BAND

3000Hz (3kHz)

300Hz

30Hz

3Hz

Frequency

Common Uses
FRS and GMRS Radios
Police and Fire
Communications

Cordless Phones
Cellular Phones

Cellular Phones

Wifi, Bluetooth

UMTS Cellular

Figure 1. International Telecommunications Union (ITU) band allotments for RF spectrum.

RF Signals
To construct an RF signal, the data to be sent must be converted to a waveform, which will be
transmitted via an antenna. To do this, as shown in Figure. 2, data is recorded and converted (if
recorded digitally) to an analog waveform. This waveform is then modulated to the carrier frequency
(88.9MHz in the case of KXJZ). This signal is amplified and transmitted via an antenna. On the
receiver’s end, the receiver would be tuned to the desired frequency. This tuning will allow the
desired signal to be passed, with all other signals (e.g. other radio stations) blocked. The signal is
then demodulated to remove the carrier and the data can then be recovered.

48

Acquire

Convert

Modulate

Transmit

Tune
Demodulate

Convert

Receive

Figure 2. RF Signal Transmission

RF Transmission and Environmental Effects
Signal Propagation
Signal propagation refers to how an RF signal reacts between the transmitter and receiver due to
effects of the environment. Buildings, foliage, distance and antennas all play a part in how a signal
goes from point A to point B. The ability to receive a transmitted signal has to do with its signal
strength at the receiver. The signal strength is affected by the transmitted power level (generally, the
higher the transmitted power, the higher the received power), obstacles such as trees and buildings
(generally, the fewer obstacles, the higher the received power) and antenna height (generally, the
higher the antennas, the higher the received power).
Cellular dead spots, FM Radio static and poor Wi-Fi reception are just some of the examples of
negative effects on signal propagation that people experience on a daily basis.
Signal Multipath
Signal multipath refers to the signal effects when it bounces around, either due to external objects
such as land (e.g. mountains) or buildings. Multipath can be noticed by a receiver as a copy of the
original signal, similar to an echo.
Signal Interference
Signal interference occurs when another signal is transmitting at the same or a similar frequency. This
can be due to the fact that signals aren’t strict in their frequencies and will “bleed” to adjacent frequency
bands, or do to multiple signals at the same frequency, particularly in unlicensed operations, such as
Wi-Fi. When multiple signals are received at the same frequency, the receiver must differentiate the
two. This can be performed using very advanced methods such as code division, where each signal
is encoded with a specific code, or very simple methods such as power levels, where the strongest
signal is used.
In a perfect world, transmission would be limited to the desired bands and on a plot of frequency,
would look like a rectangle. Unfortunately, due to the real world effects on RF signals, signals tend
to look like figure 3 below, with power at the frequencies trailing off as you get further and further
from the desired frequency. This effect is called roll-off. This creates areas of overlap and therefore,
interference, as one signal is intruding on the space reserved for another.

49

Figure 3. Real-world Transmission Problems

Guard bands are implemented to help alleviate this problem. Guard bands are frequency allotments
that nobody can transmit in. But they only help so much. In many cases, interference from signals
exceeds these guard bands and still overlaps into the adjacent frequency.

50

Figure 4. Guard Bands

51

Summary
In summary, an RF signal is energy transmitted at a certain frequency, which is effected by many
outside influences. In many ways, RF is very similar to holding a discussion at a loud cocktail party.
Many of the functions have an analogous equivalent, as shown in the table below.
Function

RF

Cocktail Party Equivalent

Signal Acquisition

Acquire Data

Speaker makes sound

Signal Conversion

Format Data

Speaker uses words

Signal Modulation

Data modulated to carrier freq.

Speaker’s voice

Signal Transmission

Carrier freq. transmitted

Speaker speaks

Signal Propagation

Path loss due to distance, environment, etc.

Difficulty hearing due to distance

Signal Multipath

Difficulty hearing due to echo,
reverb

Signal Interference

Other signals at the same, or close
frequencies

Other speakers in the room

Signal Tuning/
Demodulation

Only the desired frequencies are passed,
undesired frequencies are blocked

Singling out the desired speakers
voice

Signal Conversion

Reading the data in the proper format

Understanding the speakers words
and language

Signal Reception

Playing data

Listening to the speaker

Table 1. Cocktail Party Comparisons

2. Communications Technologies
Mobile Phone Technology
There are many types of mobile communications technologies. The most common are cell phones.
Cell phones can be characterized by their radio access technologies, such as CDMA, GSM, iDEN,
WCDMA and LTE. These technologies determine the way in which data is transmitted between the
cell phone and the cell tower.
Multiple carriers provide service utilizing various access technologies in the state of California.
Licensed network operators in California, and their radio access technologies are shown in the table
below.
Operator

Radio Access Technologies

AT&T Wireless

GSM, GPRS, EDGE, UMTS/HSPA, LTE

Cricket

CDMA, CDMA2000, EV-DO

Metro PCS

CDMA2000, EV-DO, LTE

Sprint PCS

CDMA2000, EV-DO, iDEN

T-Mobile

GSM, GPRS, EDGE, UMTS

Verizon Wireless

CDMA, CDMA2000, EV-DO, LTE
Table 2. Network Operators in California

52

Mobile Phone Standards
Three families of cellular standards exist, and each is overseen by a standards organization. These
organizations are known as the 3rd Generation Partnership Project (3GPP), which sets the standards
for GSM based systems; 3rd Generation Partnership Project 2 (3GPP2), which sets the standards for
CDMA based systems; and the Institute of Electrical and Electronics Engineers (IEEE), which sets the
standards for WiMax based systems. The standards bodies have developed wireless communication
network protocols that are categorized by generation, and referred to as 1G, 2G, 3G and 4G.

Figure 5. Defining Generations of Networks

First generation (1G) networks (e.g. Analog AMPS) were analog, voice-only, circuit switched
networks, creating a wireless parallel to the common wire line telecommunications infrastructure.
Second generation (2G) networks (e.g. GSM, CDMA) advanced the existing networks by upgrading
to digital technologies that provided a more efficient use of resources. Enhancements were made to
2G networks to add a packet-switched data overlay to the existing networks. These enhancements
were referred to as both 2.5G and 2.75G (e.g. GPRS, EDGE, CDMA2000 1xRTT). Third generation
(3G) networks (e.g. CDMA2000 EV-DO Rev 0, UMTS) were required to meet a new international
standard, IMT-2000, which placed requirements on data transfer, most noticeably a transfer speed
in excess of 200kbits/second. The networks were enhanced with an all-IP based overlay, commonly
referred to as 3.5G (e.g. CDMA2000 EV-DO Rev. A, UMTS/HSPA). The newest generation, fourth
generation (4G) networks (e.g. LTE Advanced and WiMax Advanced), is currently being deployed as
all-Internet Protocol (IP) networks. These networks treat all traffic (including voice) as data, so voice
is provided through Voice-over-IP (VoIP) protocols. These networks are required to meet the IMTAdvanced standard, which places additional requirements on data transfer, notably transfer speeds
in excess of 100Mbits/second for mobile users and 1Gbit/second for stationary users. The following
table summarizes the common network protocols by generation and standards body.

53

Generation

Family

Voice Protocol

Data Protocol(s)

AMPS

N/A

3GPP

GSM

Circuit-Switched Data

3GPP2

CDMA

Circuit-Switched Data

3GPP

GSM

GPRS (2.5G), EDGE (2.75G)

3GPP2

CDMA2000

CDMA2000 1xRTT

3GPP

GSM

UMTS, WCDMA

3GPP2

CDMA2000

CDMA2000 1xEV-DO

3GPP

GSM

HSPA, LTE

3GPP2

CDMA2000

CDMA2000 1xEV-DO Rev A

IEEE

N/A

Mobile WiMax

3GPP

N/A

LTE-Advanced

IEEE

N/A

WiMax-Advanced

1G
2G
2G+
3G
3G+

4G

Table 3. Common Network Protocols by Generation and Standards Body

Regardless of the technology implemented, all mobile communication systems rely on a network
of terrestrial cellular towers with antennas to provide coverage to a given geographic area. Cell
towers are typically located in a manner to prevent them from interfering with each other. The
telephone carriers are allocated FCC licensed frequencies, so that extraneous interference should be
minimized. The selection of a particular tower a cell phone will connect to at any one time depends
on many variables such as signal strength. A cell phone will attempt to connect with a rogue device
emulating a tower if it meets the necessary criteria and operates on the appropriate frequencies.
Network Identities
CDMA devices use an electronic serial number, known as the Mobile Equipment IDentifier (MEID)
embedded in their devices, while GSM devices utilize the IMEI (International Mobile Equipment
Identifier) to identify the phone equipment and the IMSI (International Mobile Subscriber Identifier),
which resides on the SIM (Subscriber Identity Module), card to identify the user.
Frequency Use
Networks operate on a variety of licensed frequency bands and a specific network’s frequency may
change based on geographic area. In the U.S., the cellular frequency bands used are the 850MHz
and 1900MHz bands for 2G, 3G and 4G networks; as well as 700MHz and 2100MHz for newer
3G and 4G networks. Foreign countries permit cell phones to operate in different frequency ranges.
Worldwide, the most common frequency bands are 450MHz, 900MHz and 1800MHz.
Locating a Cellular Phone
Locating a cellular phone can be done in multiple ways. From the network side, it is possible to
identify which cellular towers are in close proximity to a specific cell phone. Typically, a cellular
phone can “see” as many as six cellular towers at any given point in time. Given the (up to) six
towers in range, and approximate RF power levels, a crude determination of location (to within 10s
or 100s of meters) can be calculated. Most modern cellular phones have GPS capabilities (due to
e911 requirements) that allow for the network to obtain the GPS location of the cellular phone.

54

Without network intervention, the presence and approximate location of a cellular phone (without
identifying the device) can be determined by looking for traffic in the cellular uplink frequency
channels. These uplink frequency channels are the range of frequencies used by cellular phones
to communicate to cellular towers. Downlink channels are the corresponding frequencies that the
cellular towers use to communicate with a cellular phone. Monitoring these frequencies will only
alert you to the presence of a cellular tower.
While locating a cellular phone using the uplink frequency channel isn’t extremely accurate, relative
power levels will provide an indication of proximity to the cellular phone. Just as a human can listen
to locate the source of a sound, an RF spectrum analyzer can listen to the RF emissions to locate the
source, in this case a cellular phone. Just as the volume gets louder as the listener nears the source
of the sound, the RF emissions get more powerful as the receiver nears the source of the emission, in
this case, the cellular phone. This is the basic premise for most cellular detection devices.
One drawback to locating a cellular phone this way is that it does require the phone to be powered
on. Phones do not emit RF energy when powered off and therefore cannot be located with this
technique. In addition, the output power level of the phone varies depending on the activity of the
phone (see Figure 6) and is directly correlated to the ability to detect the RF emission. As such it is
much easier to detect the presence of a cellular phone when in an active voice session, and much
harder to detect when idle.

Figure 6. Power level of the phone varies depending on the activity of the phone

55

Wi-Fi (WLAN) Technology
Wi-Fi is probably the most ubiquitous wireless network technology. It is based on the IEEE 802.11
standards. Specifically, 802.11a, 802.11b, 802.11g, 802.11n and 802.11p provide the specifications
for wireless Ethernet systems. With the maturity of Voice over Internet Protocol (VoIP) technology,
Wi-Fi networks are increasingly being used for voice communications and can be accessed via
many cellular phones. Wi-Fi networks operate in unlicensed frequency ranges, the most common of
which reside in the 2.4GHz and 5GHz bands. However the IEEE 802.11 working group is studying
the use of 60Ghz band systems. Current MAS implementations do not address Wi-Fi devices.
Satellite Communications Technology
Satellite phones are mobile phones that connect to a satellite rather than a terrestrial tower. The
satellite transmission is in the L band range (1-2 GHz). Due to advancements in electronics, the size
of the satellite phones has decreased significantly in the last 10 years. Satellite phone calls are very
difficult to intercept, as they only require an unobstructed path to the orbiting satellite. Current MAS
implementations do not address satellite phones.
Other (Ham Radio, Walkie-Talkie, CB, Etc.)
Point-to-Multipoint Radios
Land Mobile Radios (LMR) are typically push to talk devices (as opposed to dialing a phone number).
They generally operate in a point to multipoint mode with multiple devices on a particular channel.
Common examples are Citizens’ Band radio and walkie-talkies. These devices can commonly be
found in the HF, VHF and UHF ranges. They operate in both licensed and unlicensed frequency
ranges and can operate over long distances. Because these devices broadcast the signal to all units
that are on the same channel, they are very difficult to deny service. Current MAS implementations
do not address point-to-multipoint radios.
Personal Area Networks (PANs)
Personal Area Networks (PANs) are low-powered communication networks intended for the transfer
of data a short distance, on the order of a few meters. These networks typically operate in unlicensed
frequency bands, such as the 2.4GHz ISM band. A new technology using unlicensed spectrum
is ZigBee. Although originally intended for data, there are Voice over ZigBee (VoZ) devices now
available. This technology is based on the IEE 802.15 standards. VoZ, Wi-Fi systems and even a GSM
base station receiver (to act as a cell tower) can all be made as DIY projects for less than $1000.
Current MAS implementations do not address personal area networks.

3. Network Operation
Mobile Phone System Operation
Mobile phones rely on a network of terrestrial base stations to operate and provide an interface to
the Public Switch Telephone Network (PSTN) to complete calls to landline telephones. A legally
operating network will require the licensing of spectrum as well as the deployment of cellular towers
to provide coverage to a geographic area. Small cellular networks can be built, without connection
to the PSTN, to provide communications over a small geographic area. For legal operation these
networks require the licensing of frequency spectrum, though it is not a technical requirement to
their implementation.
In order for a mobile phone to place or receive calls (or SMS messages or data services), the phone
must first register with the network. Once registered, the mobile phone will remain in communication
with the network providing information on state and allowing for handoffs from one cell tower to
another as the mobile phone moves or due to network traffic.

56

Wi-Fi-Based Phone System Operation
Wi-Fi devices do not require similar infrastructure to operate as a cellular phone. Wi-Fi devices can
connect via the “infrastructure” method, which utilizes a Wi-Fi access point, or via the “Peer-toPeer” method, which allows devices to communicate directly. Because no infrastructure is required,
it is much easier to set up and tear down a Wi-Fi based communications network than a cellular
communications network.
Satellite Phone System Operation
Satellite phones communicate with space-based satellites which in turn communicate with terrestrial
ground stations to connect to the PSTN. Because of the nature of satellite communications and the
physics involved, typically a clear view of the satellite is required for a call to be placed.
These techniques have a long history in the search for contraband RF equipment, since all RF
equipment, by definition, broadcasts at some frequency (or frequencies). For most transmission
mediums, including cellular phones, any RF receiving equipment tuned to look at the proper
frequency will be able to determine that a transmitter is operating by seeing the relative power levels
at a given frequency. In the licensed cellular bands, it can be assumed that any emitter in these
frequency bands is a cellular phone.

Figure 7: Noise Floor of 850MHz Cellular Band (No Transmitters Present)

57

Figure 8: Power Level of Transmitting Cellular Phone

There are two standard types of detection techniques: Active and Passive. Active techniques rely on a
signal output by the detection device which requests that all cellular phones in the surveillance area
respond. This technique can be used to target individual devices once the IMEI or IMSI is known.
Passive techniques rely on the reception of signals typically transmitted from a cellular handset to the
base station (tower). In neither case is the content of the communication known.
In either technique, the relative signal strength determines the range to the handset. Absolute signal
strength cannot be used because most cellular networks utilize power control in order to save battery
power (cellular phones transmit at the lowest possible power level in order to close the link with the
tower). When the signal from a specific cellular phone gets stronger at the detector, the detector is
getting closer to the targeted cellular phone. By utilizing a direction finding (DF) technique (such as
triangulation) the location of the handset can be determined.
Benefits
There are many benefits to detection techniques for locating and identifying contraband cell phones.
These include ease of use, low cost, legality and covertness.
Ease of Use
Detection techniques are relatively easy to use. A portable RF receiver is tuned to the desired
frequency. Once an emitter is found, the signal levels can be tracked in order to determine the
location of the emitter.

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Low Cost
The hardware required for detecting a cellular signal is not specialized or expensive. Systems
that are able to identify devices become more expensive due to the nature of the algorithms and
the additional processing required.
Legality
The use of passive cell phone detection equipment is legal and is not regulated by any FCC statute.
Because active cell phone detection equipment requires transmission of signals on licensed
bands, FCC regulations would restrict use of active cell phone detection equipment. Use of
active equipment would require coordination with the FCC and the owners of the frequency
spectrum.
Covertness
Passive cell phone detection equipment does not transmit any signal and is therefore undetectable
by the cellular phone. Users of contraband cell phones will have no indication if cell phone
detection equipment is deployed and currently locating their cell phone.
Active cell phone detection equipment will typically look like a cellular phone tower to which
the cellular phone cannot connect. This process would occur in the background and the user
would not be aware of the occurrence.
Drawbacks
Drawbacks to cell phone detection techniques include the fact that it does not interdict a cell phone
call, it is manpower intensive, and it requires the device to be powered on.
Does not Interdict a Cell Phone Call
Detection techniques merely detect the presence of a powered-on cell phone. These techniques
will not prevent calls or text messages from being placed.
Manpower Intensive
Since each detector needs to be mobile to effectively locate a device, it requires a commitment of
manpower to operate multiple detectors. While a fixed detector arrangement could be installed
into a facility, the amount of physical integration required would be high.
Requires the Cellular Device to be Powered On
The detector can only operate when a cellular phone is powered on, therefore the device must
be powered on during the entire detection session. If an inmate were to power on a cellular
phone for a short period of time only to receive and send a couple of text messages, or place one
short duration call, it would be difficult for detection techniques to locate this user.
Comparison with Managed Access Technologies
Cell phone detection can provide the location of contraband cellular phones during some usage
scenarios. Because these techniques do not prevent cellular phones from making or receiving calls,
or sending or receiving text messages, this technique requires further action to prevent unwanted
communications from occurring. Detection techniques have been implemented in prison facilities
around the country to detect contraband cellular phones.
Examples of Detection Technologies
ITT Exelis manufactures the CellHound cellular detection system that monitors the cellular frequency
bands using distributed, fixed mounted receivers that are networked together. The system has a 100-

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foot range and alerts the command center when a device is present and locates the device to an area
approximately the size of three prison cells.
Cellbusters manufactures the Zone Detector system, which monitors both the cellular frequency
bands as well as the 2.4GHz ISM band using distributed, fixed mounted receivers that are networked
together. The system has a 100-foot range and alerts the command center when a device is present
and locates the device to approximately 10 feet.
BVS manufactures the Wolfhound Pro system, which monitors the cellular frequency bands using a
handheld receiver. The system has a 50-foot range and alerts the operator when a device is present
and locates the device to approximately 10 feet. Netline, CJAM and SecIntel also manufacture cell
phone detection equipment.
Jamming Techniques
Overview
Jamming techniques utilize a wide-band RF transmitter to transmit noise at the frequencies which are
to be jammed. This noise makes it hard for communications to occur at the frequencies and therefore
would inhibit the use of contraband cell phones in the area of interest. Jammers can be thought of as
analogous to somebody shouting loudly in close proximity. The shouting will drown out most of the
normal conversations making it difficult to talk normally. When this occurs in an RF communication
system, the link between the cell phone and the tower cannot be made and results in a denial of
service to the user.
Benefits
There are three main benefits to the use of jamming: Ease of Use, Cost and Preventing Calls.
Ease of Use
Jammers are easy to use and set up, since they are by their very nature, a simple RF device.
Transmitters are placed in areas that need to be covered and the resulting output signal provides
enough noise in order to prevent communications over the frequencies in that area.
Cost
Jammers require no specialized hardware in order to operate, therefore are very inexpensive
to build and maintain.
Preventing Calls
Jammers will prevent the connection between a cell phone and tower thereby preventing any
communications over the cellular network. This will therefore prevent even short duration
sessions from occurring.
Drawbacks
There are many potential drawbacks to jamming techniques, including interference with adjacent
bands, inability to discriminate between users, difficulty in limiting the area, the overt nature of the
technology, and the legality of jamming.
Interference with Adjacent Bands
It is very difficult to create jammers that affect only specific frequencies while not affecting
close by frequencies. This is particularly true in the lower 800MHz bands where cellular phone
frequencies are very close to public safety frequencies. It is likely that any jammer that is
effective at disallowing cellular phones that use the 850MHz spectrum allotment would also

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be an effective jammer of the public safety frequencies.

Figure 9. Public safety and cellular bands

Inability to Discriminate between Users
Jammers are a non-intelligent system, meaning that they do not have any knowledge of the users
they are jamming. Therefore the lawful use of cellular devices is prevented just as well as the
unlawful use. While inside the prison itself this may not be an issue, when coupled with the
difficulty in limiting the affected area, this can prevent cell phones from being used near prisons
as well (such as adjacent roads, etc.).
Difficulty in Limiting the Area of Coverage
Because of the nature of RF propagation, it is not possible to precisely limit the coverage area for
an RF jamming signal. Due to the environment, coverage in one direction may be much greater
than coverage in another. This allows for two issues to occur: unintended denial of services and
jamming “deadspots”.
Unintended denial of services occurs when the jamming signal extends beyond the desired
coverage area. In the case of prisons, this could mean a road adjacent to the prison, or even parts
of the prisons not used by inmates, which may allow the use of cellular phones.
Jamming “deadspots” occur where the jamming signal is not strong enough due to environmental
effects and will not jam a cellular signal in that area. Unlike traditional “deadspots”, jamming
“deadspots” mean that the jamming signal isn’t received, but the towers signal may still be
received, resulting in pockets of coverage (instead of pockets of no coverage). Over time, these
locations may become known to the prison population, and the use of cell phones will migrate
to these physical locations.

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Overt
A jamming signal is overt. It can be easily detected and is apparent to the user when they no longer
have service where service was once present. This may or may not be an issue in the prison scenario.
Legality
Jammers are illegal to operate in the United States. The FCC forbids the use of jamming equipment in
licensed bands (including cellular) without an FCC waiver. However South Carolina prison officials
received FCC approval to test jamming technology that intercepts and terminates cell phone calls.
South Carolina officials reported that the technology was very effective at jamming cell signals
without interfering with cell signals in areas adjacent to the facility. However, the approval to test
was for a limited time and the FCC has not granted approval to implement the use of jamming
technology.30
Comparison with Managed Access Technologies
Jammers can provide many of the same benefits of managed access systems (mainly denial of
service) at a much lower cost. But there are drawbacks to the technique including the inability to
discriminate users, unintended denial of service and legal right to operate the jammers in licensed
bands. Netline, CJam, and SecIntel all manufacture cellular jammers.
Security Screening Techniques at Points of Ingress and Egress
Overview
Standard inspection techniques, such as metal detectors and x-rays can be used to identify
mobile phones at entry points. These techniques focus on detecting the devices, or parts of the
device, and would require physically removing the device after detection. Metal detectors and
x-rays are commonly used to search for contraband devices in prisons, airports and other secure
facilities. New York has trained dogs to detect certain components found in cell phones and has
implemented their use at Riker’s Island.
Benefits
Security screening techniques are well understood due to their common use. Rather than
identifying a device only when in use, as many of the RF based systems do, this technique
identifies devices that are not operating, as well as operating.
Drawbacks
A thorough security screening can be manpower intensive and does not target contraband
cellular phones specifically.

30	 Special Report- “Inmate Cell Phone Use and Endangers Prison Security and Public Safety”, Office of the Inspector General,
David R. Shaw, Inspector General, State of California, May 2009.

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Appendix 9: Technical Evaluation Report: CCST Challenges, Sandia National
Laboratory, April 2012

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Bibliography - Source Documents
Legislative Request Letter to CCST Requesting a Study on Technology to Prevent Cell Phone Use in
California Prisons
Request Letter to CCST from Senators Alquist, Hancock, Kehoe and Padilla, July 7, 2011
Letter From Senators to CDCR Secretary Matthew Cate
Letter to Matthew Cate,
November 6, 2011
CCST Contraband Cell Phones in Prisons Letter to Senators
Letter to Senators,
October 28, 2011
State of California Department of General Services
(IFB) Invitation for Bid - Inmate Ward Telephone System and Managed Access System Services
Report
California Technology Agency, July 7, 2011
Bid RFI 10-001 - Cell Phone Interdiction: Shawntech Communications Pilot Response (Bid)
April 2011
Addendum to the Inmate/Ward Telephone System and Managed Access System Invitation for Bid
(IWTS/MAS IFB)
IWTS Call Analysis - California Department of Corrections and Rehabilitation
Daily Phone Analysis (March 11-15, 2011)
March 2011
C5 System - Testing Results for CDCR SOL Facility
March 2011
Inmate Ward Phone System
Inmate Ward Telephone System - Solano State Prison Overall Call Volume 2009-2011
March 2011
SOL - Facility 1 - Daily Phone Analysis
March 2011
Comparing Inmate telephone use for Yard 1 against Yards 2 through 3 for the last 26 days
SOL Total Number of Completed Calls 2009 through 2011 By Day of Week (2/18 – 3/16/11)
SOL Take Nightops by Provider (March 24, 2011)
U.S. Department of Commerce
Contraband Cell Phones in Prisons: Possible Wireless Technology Solutions
December 2010
Office of the Inspector General
Special Report: Inmate Cell Phone use Endangers Prison Security and Public Safety
Office of the Inspector General, 2009
Articles
Inmates Harass Victims via Facebook
The Associated Press, November 21, 2011
Background Materials
Cell Phones in Prison
By: Tim Vice, Cell Phone Interdiction Manager, California Department of Corrections and

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Rehabilitation
Bureau of Prisons: Improved Evaluations and Increased Coordination Could Improve Cell Phone
Detection
September 2011
Electronic Searches of Bureau of Prison Staff Protocols

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Glossary
3GPP
3GPP2
Bluetooth
Circuit-Switched (CS)
Code Division Multiple Access
(CDMA)
CDMA2000
Cell Phone
Contraband Cell Phone
Cell Phone Carrier/Provider/
Network
Enhanced Data Rates for GSM
Evolution (EDGE)
General Packet Radio Service
(GPRS)
Global System for Mobile
Communications (GSM)
Institute of Electrical and
Electronics Engineers (IEEE)
Internet Protocol (IP)
Invitation for Bid (IFB)
Licensed Frequency Bands

Long Term Evolution (LTE)
MicroSD Cards
Managed Access System (MAS)

Packet-Switched (PS)
Personal Area Network (PAN)

Specification writing body for the GSM (including GPRS, EDGE,
UMTS and LTE) family of standards.
Specifications writing body for the CDMA (including CDMA2000)
family of standards.
Short-range RF communications protocol standardized by the
Bluetooth Special Interest Group (SIG).
A telecommunications network that requires a dedicated path
between the two nodes.
One of two major cellular radio technologies. Invented by Qualcomm
and used primarily by Sprint and Verizon Wireless in the United States.
Advanced CDMA standard adding high-speed data capabilities to the
CDMA standard.
Radio-telephonic instrument used to make telephone calls, send and
receive text (SMS and MMS) message, or send and receive data using
licensed radio spectrum.
Cell phones in the unauthorized possession of inmates in the
confinement of prisons.
Company, which operates a cellular network, such as AT&T Wireless,
Sprint, T-Mobile and Verizon Wireless in the United States.
High-speed data capability for GSM networks. Typically referred to as
a 2.75G network standard.
High-speed data capability for GSM networks. Typically referred to as
a 2.5G network standard.
One of two major cellular radio technologies. Primarily used by AT&T
Wireless and T-Mobile in the United States.
Specifications writing body for the WiMax family of standards.
Primary protocol for transferring data packets on the Internet.
Formal request for proposal by the California state government.
Bands of the RF spectrum set aside for licensed operation only.
Cellular frequency bands, TV and Radio transmission frequencies are
examples of licensed frequency bands. An FCC license is required to
transmit in licensed frequency bands.
All-IP advanced wireless standard from the 3GPP specifications body.
Can refer to both LTE, and LTE Advanced services.
A flash memory card used in cell phones measuring only 11mm x
15mm.
A cellular network system which manages user access to cellular
networks by preventing unauthorized users from connecting to a
public cellular network, while allowing authorized users to connect to
public cellular networks.
A telecommunications network that utilizes a shared-path between
nodes, segmenting traffic into packets for transmission between nodes.
Short-range, low-power wireless data networks used for the
transmission of (typically) small amounts of data. Examples of PAN
technology include Bluetooth and Zigbee.

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Unlicensed Frequency Bands

Wireless Fidelity (Wi-Fi)
WiMax
Wireless Local Area Network
(WLAN)

Bands of the RF spectrum set aside for unlicensed operations. The
Industrial, Scientific and Medical frequency bands are examples
of unlicensed frequency bands. An FCC license is not required to
transmit in unlicensed frequency bands as long as certain regulations,
such as power levels, are observed.
Most common standard of Wireless Local Area Network technology.
Defined by the IEEE 802.11 family of standards.
All-IP advanced wireless standard from the IEEE specifications body.
Can refer to both WiMax, and WiMax Advanced services.
Medium-range (up to 100s of meters) wireless data networks used
for the transmission of large amounts of data. An example of WLAN
technology is Wi-Fi.

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Cover Photo Credits
© iStockphoto.com/ccstaccountant
Production Team
CCST Executive Director, Susan Hackwood
Project Team
Cover, Layout and Design, Sandra Vargas-De La Torre