Netopia 2200 manual Policy-based Routing using Filtersets, TOS field matching, 173

Policy-based Routing using Filtersets

Policy-based Routing using Filtersets

Netopia Firmware Version 7.6 offers the ability to route IP packets using criteria other than the destination IP address. This is called policy-based routing.

You specify the routing criteria and routing information by using IP filtersets to determine the forwarding action of a particular filter.

You specify a gateway IP address, and each packet matching the filter is routed according to that gateway address, rather than by means of the global routing table.

In addition, the classifier list in a filter includes the TOS field. This allows you to filter on TOS field settings in the IP packet, if you want.

To use the policy-based routing feature, you create a filter that forwards the traffic.

•Check the Forward checkbox. This will dis- play the Force Routing options.

•Check the Force Route checkbox.

•Enter the Gateway IP address in standard dotted-quad notation to which the traffic should be forwarded.

•You can enter Source and Destination IP Address(es) and Mask(s), Protocol Type, and Source and Destination Port ID(s) for the

filter, if desired.

TOS field matching

Netopia Firmware Version 7.6 includes two parameters for an IP filter: TOS and TOS Mask. Both fields accept values in the range 0

– 255.

Certain types of IP packets, such as voice or multimedia packets, are sensitive to latency introduced by the network. A delay-sensitive packet is one that has the low-latency bit set in

the TOS field of the IP header. This means that if such packets are not received rapidly, the quality of service degrades. If you expect to route significant amounts of such traffic you can configure your router to route this type of traffic to a gateway other than your normal gateway using this feature.

The TOS field matching check is consistent with source and destination address matching.

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