Policy Routing Technical Reference; Nat And Snat; Port Triggering - ZyXEL Communications ZyWALL USG 300 User Manual

Table 81 Network > Routing > Static Route > Add (continued)
LABEL
Gateway IP
Interface
Metric
OK
Cancel

12.4 Policy Routing Technical Reference

Here is more detailed information about some of the features you can configure in
policy routing.

NAT and SNAT

NAT (Network Address Translation - NAT, RFC 1631) is the translation of the IP
address in a packet in one network to a different IP address in another network.
Use SNAT (Source NAT) to change the source IP address in one network to a
different IP address in another network.

Port Triggering

Some services use a dedicated range of ports on the client side and a dedicated
range of ports on the server side. With regular port forwarding, you set the port(s)
and IP address to forward a service (coming in from the remote server) to a client
computer. The problem is that port forwarding only forwards a service to a single
IP address. In order to use the same service on a different computer, you have to
manually replace the client computer's IP address with another client computer's
IP address.
Port triggering allows the client computer to take turns using a service
dynamically. Whenever a client computer's packets match the routing policy, it
can use the pre-defined port triggering setting to connect to the remote server
without manually configuring a port forwarding rule for each client computer.
ZyWALL USG 300 User's Guide
DESCRIPTION
Select the radio button and enter the IP address of the next-hop
gateway. The gateway is a router or switch on the same segment as your
ZyWALL's interface(s). The gateway helps forward packets to their
destinations.
Select the radio button and a predefined interface through which the
traffic is sent.
Metric represents the "cost" of transmission for routing purposes. IP
routing uses hop count as the measurement of cost, with a minimum of 1
for directly connected networks. Enter a number that approximates the
cost for this link. The number need not be precise, but it must be 0~127.
In practice, 2 or 3 is usually a good number.
Click OK to save your changes back to the ZyWALL.
Click Cancel to exit this screen without saving.
Chapter 12 Policy and Static Routes
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