Cabletron Systems CyberSWITCH CSX200 Configuration Manual

Also see for CyberSWITCH HSIM-W6: Setup guide User guide User guide Installation guide

Contents

Configuration with QuickSET128QuickSET Configuration GuideNext HopEntries in RIP-2 routing tables always have a Next Hop field. The Next Hop is the IP address of thenext router along the path to the destination. The purpose of the Next Hop in the routing table is toprevent packets from being routed through extra hops in the system. The limitation of a maximumnetwork diameter of 15 hops for the Next Hop field is common to both RIP-1 and RIP-2. Thisstatement of the limit assumes that a cost of 1 is used for each network (see Metrics, below). TheNext Hop field will contain a number between 1 and 15 inclusive. A number of 16 means that thenetwork is unreachable.MetricsThe RIP-1 and RIP-2 protocols use fixed “metrics” to compare alternative routes. This is notappropriate where routes need to be chosen based on real-time parameters such as measured delay,reliability, or load. RIP is intended to allow routers to exchange information for computing routesthrough an IP-based network. Any router that uses RIP is assumed to have interfaces to one ormore networks, otherwise it isn't a router. These are referred to as directly connected networks.The RIP protocol relies on access to certain information about each of these networks, the mostimportant of which is its metric. This metric represents the total “cost” of getting a datagram fromthe router to that destination.The routing table has the entries listed below for each destination that is reachable:• The IP prefix of the destination• A metric, described above• The IP address of the next router along the path (the Next Hop)• A flag to indicate the information about the route has changed recently• Various timers associated with the routeSplit HorizonSplit Horizon is an algorithm for avoiding problems caused by including routes in the updates sentto the gateway from which they were learned. The basic split horizon algorithm omits routeslearned from one neighbor in updates sent to that neighbor.