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a
GAO
United States Government Accountability Office
Report to Congressional Requesters
May 2005
INTERNET PROTOCOL
VERSION 6
Federal Agencies
Need toPlanfor
Transition andManage
Security Risks
GAO-05-471
What GAO Found
United States Government Accountability Office
Why GAO Did This Study
Highlight s
Accountability Integrity Reliability
www.gao.gov/cgi-bin/getrpt?GAO-05-471.
To view the full product, including the scope
and methodology, click on the link above.
For more information, contact David Powner
at (202) 512-9286 or Keith Rhodes at (202)
512-6412.
Highlights of GAO-05-471, a report to
congressional requesters
Ma
y
2005
INTERNET PROTOCOLVERSION 6
Federal AgenciesNeedtoPlanfor
Transition andManageSecurityRisks
The key characteristics of IPv6 are designed to increase address space,
promote flexibility and functionality, and enhance security. For example, by
using 128-bit addresses rather than 32-bit addresses, IPv6 dramatically
increases the available Internet address space from approximately 4.3 billion
addresses in IPv4 to approximately 3.4 × 10
38
in IPv6 (see figure).
Comparison of IPv4 and IPv6 Address Spaces
Source: GAO.
= 8 bits
= 16 bits
32-bit IPv4 address
YYY
YYY
YYYYYYYYY
128-bit IPv6 address
(Resulting in approximately 4 x 10
9
unique IP addresses)
(Resulting in approximately 3.4 x 10
38
unique IP addresses)
Describes network location Provides unique identifying number
X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X
X X X X
Key planning considerations forfederalagencies include recognizing that the
transition is already under way, because IPv6-capable software and
equipment already exists in agency networks. Other important agency
planning considerations include developing inventories and assessing risks;
creating business cases that identify organizational needs and goals;
establishing policies and enforcement mechanisms; determining costs; and
identifying timelines and methods for transition. In addition, managing the
security aspects of an IPv6 transition is another consideration since IPv6 can
introduce additional securityrisksto agency information. For example,
attackers of federal networks could abuse IPv6 features to allow
unauthorized traffic or make agency computers directly accessible from the
Internet.
DOD has made progress in developing a business case, policies, timelines,
and processes for transitioning to IPv6. Despite these efforts, challenges
remain, including finalizing plans, enforcing policy, and monitoring for
unauthorized IPv6 traffic. Unlike DOD, the majority of other major federal
agencies reported not yet having initiated key planning efforts for IPv6. For
example, 22 agencies lack business cases; 21 lack transition plans; 19 have
not inventoried IPv6 software and equipment; and none had developed cost
estimates.
The Internetprotocol (IP) provides
the addressing mechanism that
defines how and where information
such as text, voice, and video move
across interconnected networks.
Internet protocolversion 4 (IPv4),
which is widely used today, may
not be able to accommodate the
increasing number of global users
and devices that are connecting to
the Internet. As a result, IP version
6 (IPv6) was developed to increase
the amount of available IP address
space. It is gaining momentum
globally from regions with limited
address space.
GAO was asked to (1) describe the
key characteristics of IPv6;
(2) identify the key planning
considerations forfederalagencies
in transitioning to IPv6; and
(3) determine the progress made by
the Department of Defense (DOD)
and other major agenciesto
transition to IPv6.
What GAO Recommends
GAO recommends, among other
things, that the Director of the
Office of Management and Budget
(OMB) instruct agenciesto begin to
address key planning
considerations for the IPv6
transition, and that agencies act to
mitigate near-term IPv6 security
risks.
Officials from OMB, DOD, and
Commerce generally agreed with
the contents of this report and
provided technical corrections,
which were incorporated as
appropriate.
Page i GAO-05-471 Internet Protocol
Contents
Letter 1
Results in Brief 2
Background 3
IPv6 Key Characteristics Increase Address Space, Improve
Functionality, Ease Network Administration, and Enhance
Security 10
IPv6 Considerations Include Significant Planning Efforts and
Immediate Actions to Ensure Security 16
Progress Has Been Made at Defense but Is Lacking at Other Federal
Agencies 24
Conclusions 30
Recommendations for Executive Action 31
Agency Comments and Our Evaluation 32
Appendixes
Appendix I: Objectives, Scope, and Methodology 34
Appendix II: GAO Contacts and Staff Acknowledgments 36
Table
Table 1: IPv6 Reported Actions of 23 CFO Agenciesto Address an
IPv6 Transition 30
Figures
Figure 1: Internet ProtocolVersion 4 Address 4
Figure 2: An InternetProtocol Header Contains IP Addresses for
the Source and Destination of Information Transmitted
across the Internet 5
Figure 3: An Example of a Network Address Translation 7
Figure 4: Comparison of IPv6 and IPv4 Address Scheme 11
Figure 5: Major Differences between the IPv6 and IPv4 Headers 13
Figure 6: Example of a Dual Stack Network 21
Figure 7: Example of Tunneling IPv6 Traffic inside an IPv4-Only
Internet 22
Figure 8: DOD Envisions Mapping the Globe with Unique IP
Addresses 25
Figure 9: DOD’s Schedule for Transitioning to IPv6 27
Contents
Page ii GAO-05-471 Internet Protocol
Abbreviations
CFO chief financial officer
DOD Department of Defense
FAR Federal Acquisition Regulation
GIG global information grid
ICANN Internet Corporation for Assigned Names and Numbers
ID identification
IETF Internet Engineering Task Force
IP Internet protocol
IPv4 Internetprotocolversion 4
IPv6 Internetprotocolversion 6
NIST National Institute of Standards and Technology
OMB Office of Management and Budget
TCP transmission control protocol
Y2K year 2000
US CERT United States Computer Emergency Response Team
This is a work of the U.S. government and is not subject to copyright protection in the
United States. It may be reproduced and distributed in its entirety without further
permission from GAO. However, because this work may contain copyrighted images or
other material, permission from the copyright holder may be necessary if you wish to
reproduce this material separately.
Page 1 GAO-05-471 Internet Protocol
United States Government Accountability Office
Washington, D.C. 20548
Page 1 GAO-05-471 Internet Protocol
A
May 20, 2005 Letter
The Honorable Tom Davis
Chairman
Committee on Government Reform
House of Representatives
The Honorable Adam H. Putnam
House of Representatives
In 2003, the President’s National Strategy to Secure Cyberspace
1
identified
the development of secure and robust Internet mechanisms as important
goals because of the nation’s growing dependence on cyberspace. The
Internet protocol (IP) is one of the primary mechanisms that defines how
and where information such as text, voice, and video moves across
networks. Internetprotocolversion 4 (IPv4), which is widely used today,
may not be able to accommodate the increasing number of global users and
devices that are connecting to the Internet. As a result, IP version 6 (IPv6)
was developed to increase the amount of available IP address space. There
has been increasing interest in this new version of IP and its implications
for federal agencies.
As agreed with your office, our objectives were to (1) describe the key
characteristics of IPv6, (2) identify the key planning considerations for
federal agencies in transitioning to IPv6, and (3) determine the progress
made by the Department of Defense (DOD) and other major federal
agencies totransitionto IPv6.
To accomplish these objectives, we researched and documented key IPv6
attributes, including security features, and analyzed technical and planning
information from experts in government and industry. Additionally, we
obtained and analyzed documents from the Department of Commerce. We
also studied DOD plans, procedures, and actions for transitioning to IPv6.
Finally, we identified efforts undertaken by the other 23 Chief Financial
1
President George W. Bush, The National Strategy to Secure Cyberspace (Washington, D.C.:
February 2003).
Page 2 GAO-05-471 Internet Protocol
Officer (CFO) Act agencies
2
to determine their progress in addressing IPv6
transition challenges. We conducted our work from August 2004 through
April 2005 in accordance with generally accepted government auditing
standards. Details of our objectives, scope, and methodology are included
in appendix I.
Results in Brief
The key characteristics of IPv6 are designed to increase address space,
promote flexibility and functionality, and enhance security. For example,
using 128-bit addresses rather than 32-bit addresses dramatically increases
the available Internet address space from approximately 4.3 billion in IPv4
to approximately 3.4 × 10
38
in IPv6. Other characteristics increase flexibility
and functionality, including improved routing of data, enhanced mobility
features for wireless, configuration capabilities to ease network
administration, and improved quality of service. Further, IPv6 integrates
Internet protocolsecurityto improve authentication and confidentiality of
information being transmitted. These characteristics offer various
enhancements relative to IPv4 and are expected to enable advanced
Internet communications and foster new software applications.
Key planning considerations forfederalagencies include recognizing that
an IPv6 transition is already under way because IPv6-capable software and
equipment exist in agency networks. Other important agency planning
considerations include: developing inventories and assessing risks;
creating business cases that identify organizational needs and goals;
establishing policies and enforcement mechanisms; determining costs; and
identifying timelines and methods for transition. As we have previously
reported, planning for system migration andsecurity are often problematic
in federal agencies. However, proactive integration of IPv6 requirements
into federal contracts may reduce the costs and complexity of transition by
ensuring that federal applications can operate in an IPv6 environment
without costly upgrades. Managing the security aspects of the transition is
another consideration, since IPv6 can introduce additional securityrisksto
agency information. For example, attackers of federal networks could
2
The 24 CFO departments andagencies are the Departments of Agriculture, Commerce,
Defense, Education, Energy, Health and Human Services, Homeland Security, Housing and
Urban Development, the Interior, Justice, Labor, State, Transportation, the Treasury, and
Veterans Affairs, the Environmental Protection Agency, General Services Administration,
National Aeronautics and Space Administration, National Science Foundation, Nuclear
Regulatory Commission, Office of Personnel Management, Small Business Administration,
Social Security Administration, and U.S. Agency for International Development.
Page 3 GAO-05-471 Internet Protocol
abuse features to allow unauthorized traffic or make agency computers
directly accessible from the Internet.
Recognizing the importance of planning, DOD has made progress in
developing a business case, policies, timelines, and methods for
transitioning to IPv6. These efforts include creating a transition office,
developing guidance and policies, drafting transition plans, and fielding a
pilot. Despite these accomplishments, challenges remain, including
finalizing plans, enforcing policy, and monitoring for unauthorized IPv6
traffic. Regarding other major federal agencies, most report little progress
in planning for an IPv6 transition. For example, 22 agencies lack business
cases; 21 lack transition plans; 19 have not inventoried IPv6 software and
equipment; and 22 have not developed cost estimates.
Transitioning to IPv6 is a pervasive and significant challenge forfederal
agencies that could result in significant benefits to agency services. But
such benefits may not be realized if action is not taken to ensure that
agencies are addressing key planning considerations or security issues.
Accordingly, we are recommending, among other things, that the Director
of the Office of Management and Budget (OMB) instruct the federal
agencies to begin addressing key IPv6 planning considerations, and that
federal agency heads take immediate actions to address the near-term
security risks.
In commenting on a draft of this report, officials from OMB, DOD, and
Commerce generally agreed with its contents and provided technical
corrections, which we incorporated, as appropriate.
Background
The Internet is a worldwide network of networks comprised of servers,
routers, and backbone networks. Network addresses are used to help send
information from one computer to another over the Internet by routing the
information to its final destination. The protocol that enables the
administration of these addresses is the Internetprotocol (IP). The most
widely deployed version of IP is version 4 (IPv4).
Internet Protocol Transmits
Information across
Interconnected Networks
The two basic functions of IP include (1) addressing and (2) fragmentation
of data, so that information can move across networks. An IP address
consists of a fixed sequence of numbers. IPv4 uses a 32-bit address format,
Page 4 GAO-05-471 Internet Protocol
which provides approximately 4.3 billion unique IP addresses. Figure 1
provides a conceptual illustration of an IPv4 address.
Figure 1: Internet ProtocolVersion 4 Address
By providing a numerical description of the location of networked
computers, addresses distinguish one computer from another on the
Internet. In some ways, an IP address is like a physical street address. For
example, in the physical world, if a letter is going to be sent from one
location to another, the contents of the letter must be placed in an envelope
that contains addresses for the sender and receiver. Similarly, if data is
going to be transmitted across the Internet from a source to a destination,
IP addresses must be placed in an IP header. Figure 2 provides a simplified
illustration of this concept. In addition to containing the addresses of
sender and receiver, the header also contains a series of fields that provide
information about what is being transmitted.
Source: GAO.
= 8 bits
32-bit IPv4 address
YYY
YYY
YYYYYYYYY
(Resulting in 4,294,967,296 unique IP addresses)
Page 5 GAO-05-471 Internet Protocol
Figure 2: An InternetProtocol Header Contains IP Addresses for the Source and
Destination of Information Transmitted across the Internet
The fields in the header are important to the protocol’s second main
function: fragmentation of data. IP fragments information by breaking it
into manageable parts. Each part has its own header that contains the
sender’s address, destination address, and other information that guides it
through the Internetto its intended destination. When the various packets
arrive at the final destination, they are put back together into their original
form.
Internet andProtocol
Management and
Development Involve
Several Key Organizations
Several key organizations play a role in coordinating protocol development
and Internet management issues, including the following:
• The Internet Corporation for Assigned Names and Numbers, (ICANN),
is a nonprofit corporation responsible forInternet address space
allocation and management of the Internet domain name system.
3
Source address
Internet protocol header
Destination address
Source: GAO.
Internet
Destination
address
Source
address
Source Destination
3
The Web site for ICANN is www.icann.org.
Page 6 GAO-05-471 Internet Protocol
• Regional Internet Registries allocate Internet address blocks from
ICANN in various parts of the world and engage in joint projects, liaison
activities, and policy coordination. The registries include the African
Network Information Center, Asia Pacific Network Information Centre,
American Registry forInternet Numbers, Latin American and Caribbean
Internet Addresses Registry, and Réseaux IP Européens Network
Coordination Centre.
• Competing companies known as registrars are able to assign domain
names, the mnemonic devices used to represent the numerical IP
addresses on the Internet (for example, www.google.com). More than
300 registrars have been accredited by ICANN and are authorized to
register domain names ending in .biz, .com, .coop, .info, .name, .net,
.org, or .pro. A complete listing is maintained on the InterNIC
4
Web site.
• The Internet Society is a large, international, professional organization
that provides leadership in addressing issues that may affect the future
of the Internetand assists the groups responsible forInternet
infrastructure standards. The Internet Society also provides legal,
financial, and administrative support to the Internet Engineering Task
Force (IETF).
5
• IETF is the principal body engaged in the development of Internet
standards. It is composed of working groups that are organized by topic
into several areas (e.g., routing, transport, security, etc.).
6
IPv4 Address Limitations
and Mitigation Efforts
Limited IPv4 address space prompted organizations that need large
amounts of IP addresses to implement technical solutions to compensate.
For example, network administrators began to use one unique IP address
to represent a large number of users. By employing network address
translation, an enterprise such as a federal agency or a company could have
large numbers of internal IP addresses, but still use a single unique address
that can be reached from the Internet. In other words, all computers behind
4
InterNIC is a registered service of the U.S. Department of Commerce. It is licensed to
ICANN, which operates the InterNIC Web site: http://www.internic.net/.
5
The Web site for the Internet Society is www.isoc.org.
6
The Web site for IETF is www.ietf.org.
[...]... IT planning efforts and immediate actions to ensure the security of agency information and networks Important planning considerations include • developing inventories and assessing risks, • creating business cases for an IPv6 transition, • establishing policies and enforcement mechanisms, • determining costs, and • identifying timelines and methods for the transition Furthermore, specific security risks. .. be needed; and • policies for configuration management methods, to ensure that agency information and systems are not compromised because of improper management of information technology and systems Without appropriate policies and effective enforcement mechanisms, federalagencies could incur significant cost andsecurityrisks As we have previously reported,14 planning for system migration and security. .. able to operate in an IPv6 environment without costly upgrades 16 48 C.F.R 39.106 Page 20 GAO-05-471 InternetProtocol Identifying Timelines and Methods forTransition Identifying timelines and the various methods available toagenciesfor transitioning to IPv6 are important management considerations The timeline can help keep transition efforts on schedule and can provide for status updates to upper management... issues—whether agenciesplantotransition immediately or not—they will face potentially increased costs andsecurityrisksFor example, if federal contracts for IT systems and services do not require IPv6 compatibility, agencies may needto make costly upgrades Finally, if not managed, existing IPv6 features in agency networks can be abused by attackers who have access tofederal information and resources... Transition Planning Efforts Unlike DOD, the majority of other federalagencies reporting have not yet initiated transition planning efforts for IPv6 For example, of the 22 agencies that responded, only 4 agencies reported having established a date or goal for transitioning to IPv6 The majority of agencies have not addressed key planning considerations (see table 1) For example, Page 28 GAO-05-471 Internet Protocol. .. the Department of Homeland Security, issued an IPv6 cyber security alert tofederalagencies based on our testing and discussions with DHS officials The alert warned federalagencies that Page 23 GAO-05-471 InternetProtocol unmanaged, or rogue, implementations of IPv6 present network management securityrisks Specifically, the US-CERT notice informed agencies that some firewalls and network intrusion... Policies and Enforcement Mechanisms Developing and establishing IPv6 transition policies and enforcement mechanisms are important considerations for ensuring an efficient and effective transitionFor example, IPv6 policies can address • agency management of the IPv6 transition, • roles and responsibilities of key officials and program managers, • guidance on planning and investment, • authorization for. .. key planning considerations and taking immediate actions to ensure the security of agency information and networks By recognizing that an IPv6 transition is under way, agencies can begin developing risk assessments, business cases, policies, cost estimates, timelines, and methods for the transition If agencies do not address these key planning issues and seek to understand the potential scope and complexities... transition tasks and milestones, and program and budget The Chief Information Officer has responsibility for ensuring a coherent and timely transition, establishing and maintaining the overall departmental transition plan, and is the final approval authority for any IPv6 transition waivers Other key players in the department’s transition are the Defense Information Systems Agency, Joint Forces Command, the... ability to accommodate new features, or extensions For example, the next header field provides instructions to the routers transmitting the data across the Internet about how tomanage the information Page 12 GAO-05-471 InternetProtocol Figure 5: Major Differences between the IPv6 and IPv4 Headers Version: Internet protocolversion number IHL: IP Header length in 32-bit words IPv4 header Version IHL . Office
Report to Congressional Requesters
May 2005
INTERNET PROTOCOL
VERSION 6
Federal Agencies
Need to Plan for
Transition and Manage
Security Risks
GAO-05-471
What. a report to
congressional requesters
Ma
y
2005
INTERNET PROTOCOL VERSION 6
Federal Agencies Need to Plan for
Transition and Manage Security Risks
The