In
addition to SMTP traffic, IMSS can
scan POP3 messages at the gateway as your clients retrieve them.
Even if your company does not use POP3 email, your employees might
access personal, web-based POP3 email accounts, which can create
points of vulnerability on your network if the messages from those
accounts are not scanned.
The most common email scanning deployments will use IMSS to scan
SMTP traffic, which it does by default. However, to scan POP3 traffic
that your organization might receive from a POP3 server over the
Internet, enable POP3 scanning.
With POP3 scanning enabled, IMSS acts
as a proxy, positioned between mail clients and POP3 servers, to
scan messages as the clients retrieve them.
To scan POP3 traffic, configure your email clients to connect
to the IMSS server
POP3 proxy, which connects to POP3 servers to retrieve and scan
messages.