Our ubiquitous network society, in which anyone can connect to the Internet at any time and from any location, is progressing at an ever-increasing rate. It requires that IPv6 (or next generation Internet Protocol), with its almost inexhaustible address space, be adopted sooner rather than later. Knowledge Center contributors Bob Fischman and Steve Grassi explain how to choose the right strategy for your IPv6 migration.
companies and organizations across our Internet-connected society,
transitioning to the next generation Internet is becoming an
increasingly imperative need. Nowhere is the need to transition to IPv6
more pressing than with the U.S. federal government.
On Aug. 2, 2005, the department of E-Government and Information Technology
of the Office of Management and Budget
issued OMB Memorandum 05-22
which directed all U.S. federal government agencies to transition their
network backbones to IPv6. The memorandum requires that the agencies'
network backbones be ready to transmit both IPv4 and IPv6 traffic, and
support IPv4 and IPv6 addresses, all by June 30, 2008.
But, transitioning to the next generation Internet has been
described by some IT professionals as something akin to changing the
engine on a moving airplane. The degree of difficulty in transitioning
to IPv6 is enormous, particularly for large, complex organizations such
as the U.S. federal government or global companies. The main hurdle
associated with wide-scale deployment of IPv6 is the problem of moving
from a large, installed base of IPv4 networks and applications. The
requirement to upgrade current networks that will enable IPv6
represents a significant economic challenge to most organizations
because of inherent legacy issues. In the case of the U.S. federal
government, some have put the price tag for transitioning to IPv6
anywhere from $25 billion to $75 billion.
Staying with IPv4 for the long term, however, is not an option. In May of 2007, the American Registry for Internet Numbers
(ARIN) issued an advisory to the Internet technical community
suggesting that transition to IPv6 will be necessary. With only 19
percent of IPv4 address space remaining, IPv6 migration will be
necessary for any application requiring ongoing availability of
contiguous IP addresses.
Transitioning to IPv6 is a necessity
It's a necessity to begin transitioning to IPv6. So, what's an
organization to do? Most IT experts agree that interoperability is the
answer. Being able to communicate between the two protocols provides
the best transition strategy. There are currently three transition
mechanisms: dual stack, tunneling and translators.
Transition mechanism #1: Dual stack
One of the main transition techniques used is the dual stack method,
which can be used in both the network nodes (workstations and servers)
and routers. In order to work effectively, the dual stack must be
implemented in all the routers in a network. There is no communication
between IPv4 and IPv6; applications must be able to support both modes.
The challenge with the dual stack method is that all network resources
need to have enough processing power and memory to support two
different IP stacks. Also, two IP stacks mean dual management
support--which increases IT expenditures.
Transition mechanism #2: Tunnels
Another transitioning technique is the use of tunnels. Tunneling
solutions encapsulate one protocol type within another protocol. This
requires a dual stack at each end of the tunnel. The routers involved
in this method must be able to map the end addresses to each other. The
engineering complexity of this method makes large-scale deployment
extremely difficult, and would undoubtedly require, for most
organizations, the support of internal and external engineering
Transition mechanism #3: Translators
A recent development in transitioning technology is a significant
promise held by translation devices. Once considered the tool of last
resort by the IETF (Internet Engineering Task Force
translation schemes are becoming increasingly popular transitioning
approaches. Translation technology is used when an IPv6-only host is
required to communicate with an IPv4 host. Translation remains the only
method of IPv6 transition that permits network nodes to completely
remove IPv4 addresses.
This offers significant advantages over other transition approaches:
the ability to integrate IPv6-only devices into their networks while
maintaining support for IPv4-only legacy devices. Plus, it preserves
end-to-end connection security and accountability. A critical aspect of
translation technology is its single-stack approach, which reduces the
amount of routing hardware needed (thereby minimizing the IT support
resources needed to maintain the network).
The single-stack approach offers a simpler, more economic path to
IPv6-only networks. As IPv6 applications emerge, IT departments can
simply remove elements of the IPv4 stack and replace them with IPv6
Select the right transitioning strategy
Recently, the IETF initiated a working group to explore translation
approaches, which suggests that the Internet technical community is
seeing translation technology in a whole new light. It is clear that
IPv6 is the answer to a ubiquitous society that desires extensions to
more devices, such as phones, PDAs, televisions, toasters and coffee
makers. IPv4 solutions proposed for scaling the Internet address space
seem only to delay the inevitable.
Migrating to IPv6 will be difficult for larger organizations, but
strategies do exist that will ease transitioning. These mechanisms are
not alternative to one another, but require that you know your
environment so that you can select the transitioning strategy that is
appropriate to your goal. For most of us, that goal is to migrate to
IPv6 inexpensively, and with few headaches.
Robert W. Fischman is VP of North American Field Operations at Stratus Technologies. He
joined the company in 1989 as the District Manager for New York
Financial Services. Throughout his tenure with Stratus, he has
continued to assume increased responsibility, reaching his current
position in 2000. Prior to joining Stratus, Robert spent 15 years at
Unisys and its predecessor, Burroughs Corporation. He has a B.A. from
Union College and an MBA from Columbia. He can be reached at firstname.lastname@example.org.
Steve Grassi is the CIO and founding partner of Ambriel Technologies.
He provides executive leadership for the strategic use of IT resources
in support of the mission and goals of the organization. Ambriel
Technologies has been certified as approved products to aid the
Department of Defense in transitioning its computer networks to
Internet Protocol Version 6. As CIO, Grassi was instrumental in the
development process of that product. He has more than 15 years of
experience developing technology solutions, including extensive
training and experience in systems engineering and project management.
He holds a degree in Computer Information Systems from Strayer
University, and numerous certifications from top hardware and software
vendors in the industry. He has taught courses for vendors of firewalls
and several third-party applications. He can be reached at email@example.com.