FAQ: What you need to know about IPv6

Computerworld - Vendors and government agencies are pushing the use of Internet Protocol Version 6 as the number of addresses available in IPv4 diminishes, and researchers find that network administrators are unprepared for the new protocol. Here's more on what you need to know about IPv6.

What is IPv6?

Internet Protocol Version 6 is a network protocol that will succeed IPv4, the protocol widely in use today. (IPv5 was designed for testing, not practical use.) Both protocols help IP-networked devices talk to one another, providing security and specific addresses for devices such as printers, desktops, servers and more.

Why change?

The biggest improvement in IPv6 is a vast increase in the number of addresses that can be doled out for networked devices. Many vendors and the American Registry for Internet Numbers, which gives out the addresses in the U.S., suggest that only 19% of the addresses for IPv4 are left, and the situation is much worse in nations outside the U.S. The University of New Hampshire's InterOperability Laboratory says its members generally believe there are only enough addresses to last until 2010 or 2012, which could pinch unprepared network administrators who are planning to buy a large amount of networked gear, all needing IP addresses, at about that time.

So how big is this IPv6?

Expressed in available addresses, it's so big that only math teachers might care. It is expressed several ways numerically: IPv4, the current one, has about 2³² (about 4.3 billion) addresses. In comparison, IPv6 has 2¹²⁸ (or 3.4 by 10³⁸) addresses or it can be expressed as 340,282,366,920,938,463,463,374,607,431,770,000,000. UNH's InterOperability Lab guru for IPv6, Erica Johnson, said one theory she learned during her research was that Ipv6 has so many addresses that it compares to the number of grains of sand on the Earth. That is certainly more lyrical than the mathematical expression and might actually impress somebody (and is, of course, impossible to disprove). A spokesman at UNH's test lab added that the number of addresses can be expressed as "nearly" 340 undecillion. (Oddly, undecillion is defined as 1 followed by 36 zeros in the U.S., but by 66 zeros in Great Britain, according to Dictionary.com.)

While we are on the subject, does IPv6 have anything to do with Moonv6?

Yes! Glad you asked. Moonv6 is a network over many sites to test the interoperability of various vendors' IPv6 hardware and software offerings. It has been in operation since 2003, using the UNH lab testbeds at the behest of a group led by the North American IPv6 Task Force and involving Department of Defense officials, the U.S. Cyberspace Security Office and others. Some 60 vendors have tested over Moonv6.