NETGEAR Nighthawk RS700 User Manual page 199

4. Noting your port triggering rule and observing the destination port number of 6667,
your router creates another session entry to send any incoming port 113 traffic to
your computer.
5. The IRC server sends a return message to your router using the NAT-assigned source
port (for example, port 33333) as the destination port and also sends an "identify"
message to your router with destination port 113.
6. When your router 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 router restores the original address information replaced by NAT and
sends this reply message to your computer.
7. When your router 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 router replaces the message's destination IP address with your
computer's IP address and forwards the message to your computer.
8. When you finish your chat session, your router eventually reaches its port triggering
time-out period due to inactivity in the communications. The router then removes
the session information from its session table, and incoming traffic is no longer
accepted on port numbers 33333 or 113.
Manage Port Forwarding and
Port Triggering
Nighthawk WiFi 7 Tri-Band Router Model RS700
199 User Manual