Thanks to Sebastien Bertholet, an esteemed engineer in the Directory services quality engineering team, for producing this amazing picture of a fully partially connected topology of 150 Master Directory Servers (each master is connected to 5 other servers).
Click on the picture for the full size version for the details, but be patient the image is huge.
Technorati Tags: directory-server, ldap, Sun
Ludo Sketches 
Wow – that’s very pretty. But how many replication agreements are there for each server? Only 6 lines are shown for each server in the picture – if it was "fully connected", then wouldn’t each server have 149 replication agreements?
Mark, you’re right. Each master is only connected to 6 other masters.
I’m correcting the post.