The Internet has grown at exponential rates since the late 1980s with the introduction and success of electronic commerce, and the wealth of information, places to go, and things to do on the Net. The Internet has simplified many ordinary tasks from shopping, to enrolling for college courses, to online banking and billing. This doing things from the "comfort of your own home" has had a tremendous success. According to NUA Ltd., global online users went from 26 million in 1995, to 605.6 million users in 2002. Of those 605.6 million users, 31.5 percent are from Europe, 30.9 from Asia/Pacific, 30.1 percent from the U.S. and Canada, 5.5 percent Latin Americans, 1 percent from Africa, and 0.8 percent from the Middle East. The Internet has not only simplified mundane activities, but has, also, served the greater good of improving and promoting research and collaboration among scientists and scholars, which have led to prominent advancements in science and technology. This advancement in science and technology require more sophisticated network infrastructure, hardware, software, applications, and underlying protocols.

The current Internet uses Internet Protocol version 4 (IPv4), which incredibly has been around for over 20 years (IPv4's RFC 791 was released in 1981.) Obviously, IPv4 is pretty resilient, and robust. However, the exponential growth of Internet users, and the inefficient allocation of IP addresses could lead to a shortage of IP addresses if there were an increase in the use of mobile devices connected to the Internet. Currently, two schemes Network Address Translation (NAT) and Classless Inter-Domain Routing (CIDR) serve as patches for expanding the pool of IP addresses, but these are not permanent solutions if the Internet is to continue to improve and innovate the medical and scientific communities. Moreover, NAT is an obstacle to the development of more sophisticated applications, and to secure end-to-end transactions. If the Internet is to continue to evolve and provide solutions to the scientific and medical communities, and everyday problems, it has to keep growing and offering sophisticated applications. As such, in 1995, the Internet Engineering Task Force (IETF) specified the Next Generation Internet Protocol, namely Internet Protocol version 6 (IPv6), in its RFC 1883 (this RFC has been obsoleted by RFC 2460.) The adoption of IPv6 has been slow. There is not much demand for it from customers. The main obstacle to deploying this protocol is the absence of an immediate need for it. There is not an absolute shortage of IP addresses, and the IPSec protocol, built into IPv6, can also be implemented with IPv4. Furthermore, mobility (Mobile IP) can be deployed using IPv4, even though Mobile IP with IPv4 generates what is called "Triangle Routing", which causes increased latency and uses more bandwidth than Mobile IPv6.

What happened to IPv5?

As mentioned previously, the Internet is currently using Internet Protocol version 4. The next generation of the internet Protocol is version 6. Curious to know what happened to version 5? Go to the References section on the side bar to find out. =>

IPv6 Capabilities/Features

• Expanded Addressing/Scalability (address size increased from 32 bits to 128 bits)
• Header Format Simplification (new IPv6 header is only twice as large as the IPv4 header, even though IPv6 addresses are four times as large as IPv4 addresses)
• Improved Support for Extensions and Options
• Flow Labeling (For QoS)
• Built-in Security (authentication, data integrity, and data confidentiality)
• Auto-configuration (RFC 2462)
• Peer-to-peer applications/transparency
• Easy renumbering

As seen above, alleviating the possible shortage of IP addresses is not the only solution provided for by IPv6. Besides increasing the number of IP addresses from around 4.3 billion (2^32) to about 340 trillion trillion trillion (2^128), IPv6 offers built-in security and mobility. These three features alone will revolutionize the Internet allowing always-on devices, global routable addresses, and secure automatic roaming between different networks for mobile devices. As mentioned earlier, security and mobility are viable with IPv4, but require extra configuration, and in the case of mobile IP increased latency and bandwidth use. In the biomedical community the benefits of IPv6 could be applied to electronic sharing of medical records on a wireless network. This technology could be used by paramedics at the scene of an accident, for instance, to gain access to the victim's records immediately, and possibly saving his life. Secure/mobile technology could also be used by ambulatory medical services, again, to access medical records.

Barriers to IPv6 Implementation

At the launch of IPv6 the greatest barrier to IPv6 implementation seemed to be a lack of hardware and software supporting IPv6. As of the date of this writing (December, 2003), that obstacle seems to have dissipated as evidenced by the 6Bone's "IPng Implementations" web page.

Status of IPv6 Deployment at the National Library of Medicine (NLM)

NLM is in the planning stage of implementing an IPv6 testbed via a native link to the Internet2 (I2). NLM has been assigned IPv6 address space from the Maxgigapop (MAX), which is the gigapop used to connect to the Internet2 network. I2 offers through Abilene, its backbone, native IPv6 services to its participants. NLM has the hardware, software, and other resources necessary to implement an IPv6 testbed. The first objective in implementing such a testbed is to gain first-hand experience configuring and operating co-existing IPv4 and IPv6 networks. Other objectives will follow, such as identifying and testing a biomedical application (advanced or high-performance) that uses, depends, or is enhanced by IPv6.