In his entry XMLRPC vs REST vs SOAP vs CIM vs RMI vs Message Bus vs … Lots of RPC Options, Michael DeHaan opens his experience with RPC protocols and pours it out on the page.

This is based on not only a few apps like Cobbler and Func, but also past work where I’ve touched almost all of these first hand — I always seem to get stuck working on the backend server components wherever I go. This is by design — I like it there.
Michael then goes down a list of RPC protocols, noting positives (+) and negatives (-) about each based on his time working with remote procedure calling. He is the founder and lead developer for Cobbler, a next generation Linux provisioning server, and a Func hacker, a “secure (and) scriptable remote control framework and API.”

(Edited to clarify that Michael is a hacker in the Func collective, not a presumptive leader.)