Mac OS X 10.5 and the LKDC:SHA1. realm

[Hamish]

Hi,

Kerberos is one of those technologies I've been meaning to find out
about but never had any real cause to, as I've never administered a
network beyond my home LAN. However, with the advent of Mac OS X 10.5
Leopard, it seems that Kerberos is now being used for authentication
on my home LAN!

Sam Hartman's page at http://www.painless-security.com/blog/2007/10/p2p-kerberos/
describes LKDC: realms (which are based on the hash of a public key)
and says that "a KDC location plugin allows the Mac to find out how to
contact the appropriate KDC for one of these peer-to-peer realms".
However, I haven't been able to find out any further information about
this from anywhere.

Does anyone know where I might find a description of this KDC location
plugin, or better yet, a fuller explanation of all of these extensions
to Kerberos?

Many thanks,
Hamish