document TCP parameters
There are several basic TCP parameters that the system supports that are not documented. The one I ran across is TCP_ABORT_THRESHOLD, which appears to determine how long data packets may be outstanding before a connection is terminated due to a timeout. HP-UX has documented this and a few similar tunables1. There's also an ARC case that describes some of them.
Even if it's not important for users to change them, it would be helpful to have documentation explain that these parameters exist so that users can understand under precisely what conditions connections may be terminated.