Appeared in Summer 2001 AEA Magazine
Why You should care about IPv6
By Brian McGehee
Few
will question the fact that the Internet has revolutionized our world. It has changed how we live our daily
lives. How we read the news, shop, do
business, and communicate with each other.
The Internet today is connecting people, businesses, organizations,
communities, and countries throughout the world.
However,
the current version of the Internet Protocol version 4 (IPv4), is suffering
under the strains of old age, abuse, and exploitation. Even the ARPA visionaries that began the
Internet in the early 70’s couldn’t predict the breadth of its proliferation
and diversity of its usage.
The
most notable concern with IPv4 is its restricted address space. IPv4 has a limitation of 232nd or
4,294,967,296 total addresses and numerous factors make many of the addresses
“unavailable” for end users (i.e. Multicasting, CIDR, etc.) There are more people in the world today than
Internet addresses and most people access the Internet form multiple locations
and multiple devices. Activities like
surfing “Internet references” from work, looking up a movie theater schedule
from a home computer, and checking stock prices from a cell phone or personal
digital assistant (PDA) all require a separate, unique IP address.
Another
problem with the original IPv4 specifications was the introduction of “classfull”
networks that pre-defined blocks of IP addresses. Organizations were issued theses large blocks
of IP addresses that often exceeded their actual requirements, which led to
wasted addresses. In the early 90’s a
new method for assigning IP addresses was implemented called Classless Inter
Domain Routing (CIDR), which extended the supply of IPv4 addresses. This allowed large IP networks to be broken
up into multiple smaller networks.
Unfortunately, each network requires a route be advertised on the
Internet so that data can find its way to that network. This has created a new problem on the
Internet of too many routes in the routing table. At the time of this writing there are over
100,000 routes on the Internet, requiring more costly hardware to support
Internet connectivity.
And
it’s not just end users that are being affected by the shortcomings of
IPv4. Business everywhere, from large
enterprises to small organizations, have adopted IP as their standard
networking protocol. Not only are they
feeling the address space shortage, but are affected by other limitations of
the IPv4 protocol. For example, the
original specifications for IPv4 didn’t consider or include features for
security, authentication, or “Quality of Service” (QOS). Working support for some of these features
was added over a decade later. Another
IPv4 addition is Network Address Translation (NAT), which allows many computers
on a corporate network to share a single Internet IP address and was readily
adopted by many companies. However,
there are several downfalls to NAT.
Besides the administration overhead, it also creates a network
bottleneck and breaks “end to end” application connectivity without specific workarounds
and fine-tuning.
Another
failing of IPv4 is its inability to provide a ubiquitous “Quality of Service”
(QoS) on networks, which has been a lost source of revenue for some network
providers. QoS allows controlled
delivery of data depending on its “classification”. For example, e-commerce traffic has critical
delivery requirements whereas web browsing doesn’t. With a QoS standard implemented worldwide,
such services as Voice Over IP (VOIP) are a global reality. In IPv4 several QoS standards (MPLS, RSVP,
etc.) have been introduced and implemented to varying degrees, but none
globally.
It
was in 1993 when the Internet community realized the need for a new protocol to
support the future of IP networking that ultimately resulted in the IPv6
standard. Today, IPv6 co-exists on the
Internet and may ultimately subsume the current protocol. IPv6 is a culmination of technology,
knowledge, and experience from the past 30 years and it incorporates the desires
of tomorrow, for creating a flexible, feature-rich protocol.
The
most notable benefit of IPv6 is the number of addresses 2128th. This works out to be
340,282,366,920,938,463,463,374,607,431,768,211,4546 addresses. Providing billions on billions of addresses
per person in the world today, quickly solving any address depletion
issues. This also alleviates any need
for businesses to use NAT.
Instead
of requiring protocols like Dynamic Host Configuration Protocol (DHCP) and
BOOTP, which have been added upon IPv4, IPv6 uses a new feature called Neighbor
Discovery for interface configuration information. This new feature allows automatic
configuration of hosts on a network, alleviating the need for extra hardware
and administrative overhead to support DHCP.
Neighbor Discover in IPv6 supports host transition from one network to
another supporting real-time roaming and wireless.
As
network devices get smaller and take advantage of wireless technology the need
for global addressability becomes more critical. Taking advantage of IPv6 technology will
allow such innovations as the “IPv6 pacemaker”.
Pacemakers that, when entering a hospital, will connect to a network and
download vital information on trending statistics, report trouble, and upload
new firmware if necessary. Standards,
like the wireless 3GPP and IPv6, will drive this technology to fruition.
IPv6
also introduces both a “Traffic Class” and a “Flow Label” feature that will be
implemented across networks ubiquitously.
This will support QoS, and allow network providers to collect billing
information on “data flows”. Providers
can better guarantee delivery of data to their customers, and bill them based
on their traffic usage.
IPv6
wasn’t developed to be a different protocol, just a better one. The creators and early adopters realized that
IPv6 must co-exist with IPv4. Currently
there are numerous methods in place to assist and facilitate the transition
from IPv4 to IPv4. Transition standards
include; dual stacking, translating, and tunneling IPv6 to and from IPv4. There are a few companies today, such as
Seattle-based Zama Networks, that are on the forefront of this technology
working to be IPv6 transition agents for the IP community.
IPv6
provides a revolutionary way to network, and with the adoption of this standard
globally, new possibilities will be realized.
More and more smart devices in the home and business will be connected
to the Internet, allowing you to activate the microwave for dinner, turn up the
thermostat for the evening, check the refrigerator for milk, and even have your
bathtub fill up all from the convenience of a PDA in your car on the way
home. No matter whether you are an end
user, a Webmaster, an e-commerce site, or a large business, IPv6 will be an
integral part of your future.
About
the Author:
Brian McGehee is a Senior Network
Engineer for Zama Networks with over 20 years of experience in the networking
and computer field. He can be contacted
via email at doc@tavian.com