3Com Switch 8800 Configuration Guide Chapter 19 OSPF Configuration19-2019.2.14 Configuring an Interval Required for Sending LSU PacketsTrans-delay seconds should be added to the aging time of the LSA in an LSU packet.Setting the parameter like this mainly considers the time duration that the interfacerequires for transmitting a packet.The user can configure the interval of sending LSU message. Obviously, more attentionshould be paid to this item over low speed networks.Perform the following configuration in interface view.Table 19-20 Configure an interval required for sending LSU packetsOperation CommandConfigure an interval for sending LSU packets ospf trans-delay secondsRestore the default interval for sending LSUpackets undo ospf trans-delayBy default, the LSU packets are transmitted per second.19.2.15 Configuring the Cost for Sending Packets on an InterfaceThe user can control the network traffic by configuring different packet sending costs fordifferent interfaces.Perform the following configuration in interface view.Table 19-21 Configure the cost for sending packets on an interfaceOperation CommandConfigure the cost for sending packets on an interface ospf cost valueRestore the default cost for packet transmission on theinterface undo ospf costFor the Switch 8800, the default cost for running OSPF on the VLAN interface is 10.19.2.16 Configuring to Fill the MTU Field When an Interface Transmits DDPacketsOSPF-running routers use Database Description (DD) packets to describe their ownLSDBs during LSDB synchronization.You can manually specify an interface to fill in the MTU field in a DD packet when ittransmits the packet. The MTU should be set to the real MTU on the interface.Perform the following configuration in interface view.