Table 10-4 lists the LSA types and their descriptions for reference; following the table, each type is explained in more detail, in the context of a working network. Table 10-4 OSPF LSA Types Before diving into the coverage of LSA types, two more definitions are needed: ■ Transit network—A network over which two or more OSPF routers have become neighbors, so traffic can transit from one to the other. ■ Stub network—A subnet on which a router has not formed ..
BGP Configuration Stencil for Large Networks
The following basic configuration summarizes the commentary of this section. It is not necessary to include the complete configuration as part of your default BGP configuration. You should study this section to see what is suitable for your environment: interface loopback 0 ip address 1.0.0.1 255.255.255.255 router bgp 100 no synchronization bgp router-id 1.0.0.1 no bgp fast-external-fallover bgp log-neighbor-changes ..
Four-Step STP Decision Sequence
When creating a loop-free logical topology, Spanning Tree always uses the same four-step decision sequence: • Lowest Root BID • Lowest Path Cost to Root Bridge • Lowest Sender BID • Lowest Port ID Bridges pass Spanning Tree information between themselves using special frames known as bridge protocol data units (BPDUs). A bridge uses this four-step decision sequence to save a copy of the best BPD..
UplinkFast: Access-Layer Uplinks
Consider an access-layer switch that has redundant uplink connections to two distribution- layer switches. Normally, one uplink would be in the Forwarding state and the other would be in the Blocking state. If the primary uplink went down, up to 50 seconds could elapse before the redundant uplink could be used. The UplinkFast feature on Catalyst switches enables leaf-node switches or switches at the ends of the spanning-tree branches to have a functioning root port whil..
v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} Frame Relay is a packet-switched technology. It is a high-speed WAN protocol designed primarily for interconnecting geographically dispersed LANs or WANs through a shared network. Frame Relay uses statistical multiplexing, which allows multiple users to access a Frame Relay virtual circuit and port from a single location. Compar..
