Good description of how Exchange Direct Push works

Search Exchange has a tutorial about configuring Direct Push in Exchange 2003 SP2 written by Exchange MVP Brien M. Posey.

Part 1 of this article has one of the best descriptions of how Direct Push works I have ever read. Well worth a read.

The article also covers Configuring Direct Push technology on Exchange Server 2003 SP2 and Configuring Direct Push technology on Windows Mobile devices