ZyXEL P-660HN-T1A Support Guide - Page 73

P-660HN Series Support Notes Use IPPR to distribute traffic among multiple paths  Benefits Source-Based Routing - Network administrators can use policy-based routing to direct traffic from different users through different connections. Quality of Service (QoS)- Organizations can differentiate traffic by setting the precedence or TOS (Type of Service) values in the IP header at the periphery of the network to enable the backbone to prioritize traffic. Cost Savings- IPPR allows organizations to distribute interactive traffic on high-bandwidth, high-cost path while using low-path for batch traffic. Load Sharing- Network administrators can use IPPR to distribute traffic among multiple paths.  How does the IPPR work? A policy defines the matching criteria and the action to take when a packet meets the criteria. The action is taken only when all the criteria are met. The criteria include the source address and port, IP protocol (ICMP, UDP, TCP,etc), destination address and port, TOS and precedence (fields in the IP header) and length. The inclusion of length criterion is to differentiate between interactive and bulk traffic. Interactive applications, e.g., Telnet, tend to have short packets, while bulk traffic, e.g., file transfer, tends to have large packets. The actions that can be taken include routing the packet to a different gateway (and hence the outgoing interface) and the TOS and precedence fields in the IP header. IPPR follows the existing packet filtering facility in style and in implementation. The policies are divided into sets, where related policies are grouped together. A use defines the policies before applying them to an 73 All contents copyright © 2010 ZyXEL Communications Corporation.