Perdition use cases
Perdition is a proxy for the POP and IMAP protocols that allows a user to connect to any Perdition server, regardless of their account's zimbraMailHost, and use a POP or IMAP client to access their mail.
Perdition is also useful for offloading the SSL connection from the tomcat server, and handling it in the proxy. This can reduce the load on the mailstore server, as well as work around some IMAP SSL bugs.
Setting the ports
"Real" and proxied ports
In any perdition setup, there are 2 ports defined for every service.