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