Thursday, December 31, 2009

IPV6, Things have changed...

Hey Guys,

Hope new years eve is finding you well. While waiting for someone to come and pick me up for a party I have been doing some IPv6 study (I sure do know how to paint the town red don't I ;).)

So, IPv6: It's coming guys. No avoiding it, I recommend if you haven't started reading up on it you better start now.

Bit of a gotcha with that though, ya see a lot of the information out on the Internet at the moment regarding IPv6 is a little outdated. With the IETF feverishly working on the RFC it's getting very hard to get a "Current state" of IPv6

Super Duper Quick Primer on IPv6:

  • All Addresses are 128 Bits Long
  • The 128 bits are made up of groupings of hexadecimal characters
  • You can compress the format of the IPv6 address to make it more readable
  • More than one address on an interface is now quite normal
  • Broadcast has been done away with
  • what bits an address start with now control what "Scope" that address is used for. The Scope defines the "Role" of that address (think loop back, or RFC 1918 addresses)

For me personally, when I did my CCIE in 2007 IPv6 was in quite a diffirent state to what it is now. Here are things that have changed since I started studying it. I hope that you find them useful.

1. Site Local Addressing = Gone

Site Local addressing has been replaced, in its place we now get "Unique Local Addressing" which is essentially the same thing, the major diffirence being what the prefix starts with (FF0C/7)

2. Before they wanted to make it so you could NOT get any address allocations directly for an enterprise, you had to go through an ISP. They have changed that now. you can get Provider indepedent addresses allocated to you should you be able to prove the need. The reason they did not want this at first was because they where worried about how big the routing tables could get if we had tons of ipv6 prefixes floating around instead of being nicely aggregated as they should be.

Thats the two major things I can see so far, I can also see they have dropped most of the IPv6 to IPv4 translation mechanisms, that I will cover later on in my next IPv6 related blog post

Untill next time!