200 Configuring Enterprise Edge ServicesEnterprise Edge 2.0 Programming Operations Guide P0911588 Issue 01IP RoutingThe IP Routing service setting allows you to select, add or delete routing protocolon specific interfaces, choose routing protocol options, and add or delete staticroutes.Enterprise Edge supports the following IP routing protocols:• Routing Information Protocol (RIP)• Open Shortest Path First (OSPF)Routing Information Protocol (RIP)Enterprise Edge supports RIP, a widely-used protocol for managing routinginformation in a self-contained network, such as a corporate intranet. RIP measuresthe shortest path between two points on a network in terms of the number of hopsbetween those points.Enterprise Edge router sends RIP routing information updates that list all the otherhosts it knows about, to its nearest neighbor host every 30 seconds. The neighborhost sends the information to its next neighbor, until all the hosts in the networkknow the routing paths, a state known as network convergence. RIP uses a hopcount to determine network distance. Each router in the network uses the routingtable information to determine the next host for the packet, until it reaches thedestination.Enterprise Edge supports on demand routing table update and periodic routing tableupdate. On demand routing table update is available only on demand-dialinterfaces. Periodic update operates efficiently on persistent linksFor information on how to select RIP as your routing protocol, see Configuring IPRouting on page 201.Open Shortest Path First (OSPF)Open Shortest Path First protocol bases its path descriptions on “link states” thattake into account additional network information. OSPF also lets the user assigncost metrics to a given host router so that some paths are given preference. OSPFsupports a variable network subnet mask so that a network can be subdivided intoareas. For information on how to select OSPF as your routing protocol, seeConfiguring IP Routing on page 201.WARNINGBecause OSPF is a “link-state” based routing protocol, you must not use OSPF ondemand dial interfaces. Frequent link status (between “up” and “down”) may causethe protocol to become unstable.
