RFC 5453 is one of the shortest RFC’s I have ever read.

RFC 5453, the most recent RFC dealing with IPv6 (a statement that will be true for about the next 10 minutes), addresses a real, albeit fairly unlikely, scenario.  The 64-bit interface identifier of a node’s global unicast address is randomly derived (via one of many possible mechanisms).  There is a possibility that a node can randomly choose an interface ID (IID) that is reserved for a standardized service or process.  This can have any number of negative effects on the unfortunate node as well as the service.

RFC 5453 simply starts a standardized list of 64-bit IIDs that are unavailable for node use.  Vendors will be able to use this list to make sure their OS’ don’t let nodes select addresses from the ranges defined in the RFC.

As of today there are two ranges defined; a short list no doubt.  It will grow over time and now there is a standardized way to keep track of them all.

Simple.  Efficient.  Necessary.

Cheers,

Colin Weaver