3Com 5500G-EI Command Reference Guide - Page 210

210 CHAPTER 6: USING ROUTING PROTOCOL COMMANDS Description Use the ospf network-type command to configure the network type of OSPF interface. Use the undo ospf network-type command to restore the default network type of the OSPF interface. OSPF divides networks into four types by link layer protocol: ■ Broadcast: If Ethernet or FDDI is adopted, OSPF defaults the network type to broadcast. ■ Non-Broadcast Muli-access (nbma): If Frame Relay, ATM, HDLC or X.25 is adopted, OSPF defaults the network type to NBMA. ■ Point-to-Multipoint (p2mp): OSPF will not default the network type of any link layer protocol to p2mp. The general undertaking is to change a partially connected NBMA network to p2mp network if the NBMA network is not fully-meshed. ■ Point-to-point (p2p): If PPP, LAPB or POS is adopted, OSPF defaults the network type to p2p. NBMA means that a network is non-broadcast and multi-accessible. ATM is a typical example. A user can configure the polling interval to specify the interval of sending polling hello packets before the adjacency of the neighboring routers is formed. Configure the interface type to nonbroadcast on a broadcast network without multi-access capability. Configure the interface type to p2mp if not all the routers are directly accessible on an NBMA network. Change the interface type to p2p if the router has only one peer on the NBMA network. When the network type of an interface is NBMA or it is changed to NBMA manually, the peer command must be used to configure the neighboring point. Related command: ospf dr-priority. Example Set the interface Vlan-interface 1 to NBMA type. system-view System View: return to User View with Ctrl+Z. [SW5500]interface Vlan-interface 1 [SW5500-Vlan-interface1]ospf network-type nbma ospf timer dead Syntax ospf timer dead seconds undo ospf timer dead View VLAN Interface View