Port Triggering - Cisco QuickVPN - PC Administration Manual

Firewall Configuration

Port Triggering

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Port Triggering
Cisco SA 500 Series Security Appliances Administration Guide
- Permit and block the rest: All addresses in the MAC Addresses table
are permitted. All other addresses are blocked.
- Click Apply to save your settings, or click Reset to revert to the saved
settings.
To add a MAC address to the table, click Add.
Other options: Click the Edit button to edit an entry. To delete an entry, check the
box and then click Delete. To select all entries, check the box in the first column of
the table heading.
After you click Add or Edit, the MAC Filtering Configuration page appears.
Enter the MAC Address.
Click Apply to save your settings, or click Reset to revert to the saved settings.
Port triggering opens an incoming port for a specified type of traffic on a defined
outgoing port. When a LAN device makes a connection on one of the defined
outgoing ports, the security appliance opens the specified incoming port to
support the exchange of data. When the exchange is completed, the ports are
closed.
Port triggering is more flexible than the static port forwarding that you can
configure in a firewall rule. Port triggering rules do not have to reference specific
LAN IP addresses or IP addresses ranges. In addition, the ports are not left open
when they are not in use, thereby providing a level of security that static port
forwarding does not offer.
Port triggering is required for some applications. Such applications require that,
when external devices connect to them, they receive data on a specific port or
range of ports in order to function properly. The security appliance must send all
incoming data for that application only on the required port or range of ports. The
gateway has a list of common applications and games with corresponding
outbound and inbound ports to open. You can also specify a port triggering rule by
defining the type of traffic (TCP or UDP) and the range of incoming and outgoing
ports to open when enabled. See Appendix B, "Standard Services."
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