I have written a OO system in Perl that connects to SMSC's of mobile operators to send SMS messages. Currently it works as follows:
The main process checks to see if there are SMS messages to be send. If there are, it forks off a child process which connects to the SMSC and sends all messages. After that, the connection is closed again.
The problem is that I need to keep the connections alive. So I have to develop some kind of socket connection pool in the main process, which the child processes can use to send their messages. The main process just needs to take care of the connections and restore them when needed.