As we saw earlier, each child server (be it a thread or a process) is engaged in processing connections. Each connection may be served by different connection protocols, e.g., HTTP, POP3, SMTP, etc. Each connection may include more than one request, e.g., several HTTP requests can be served over a single connection, when several images are requested for the same webpage.
The following diagram depicts the connection life cycle and highlights which handlers are available to mod_perl 2.0:
