Control Access to the Internet
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VDSL Voice Gateway
6.
When your gateway receives the incoming message to destination port 33333, it checks its
session table to see if a session is active for port number 33333. Finding an active session,
the gateway restores the original address information replaced by NAT and sends this reply
message to your computer.
7.
When your gateway receives the incoming message to destination port 113, it checks its
session table and finds an active session for port 113 associated with your computer. The
gateway replaces the message’s destination IP address with your computer’s IP address
and forwards the message to your computer.
When you finish your chat session, your gateway eventually senses a period of inactivity in the
communications and removes the session information from its session table, and incoming traffic
is no longer accepted on port numbers 33333 or 113.