Using Sync and Redistributing Routes
BGP synchronization is best understood when considered in the context in which it was intended to be used—namely, in conjunction with the redistribution of BGP routes into the IGP. This method is seldom used by ISPs today, mainly because of the large number of routes that would be injected into the IGP. However, using BGP sync in conjunction with redistribution solves both problems related to the routing black hole. The key to understanding BGP sync is to know that redistr..
ERSPAN supports source ports, source VLANs, and destinations on different switches, which provides remote monitoring of multiple switches across your network (see Figure 41-3). ERSPAN uses a GRE tunnel to carry traffic between switches. ERSPAN consists of an ERSPAN source session, routable ERSPAN GRE-encapsulated traffic, and an ERSPAN destination session. You separately configure ERSPAN source sessions and destination sessions on different switches. To configure an ERSPAN so..
When building a wireless LAN based on Cisco SWAN, a company must choose components designed to fit into the architecture. Cisco SWAN includes the components described in Table 23-2. Table 23-2 Cisco SWAN Hardware
In recursive lookup, the next hop for IBGP routes is not directly connected. This problem must be resolved, as shown in the following output of show ip route for an IBGP-learned route: Routing entry for 200.200.200.0/24 Known via "bgp 2", distance 200, metric 0 Tag 1, type internal Last update from 171.68.181.1 00:45:07 ago Routing Descriptor Blocks: * 171.68.181.1, from 150.150.3.11, 00:45:07 ago Route metric is 0, traf..
Setting Payload Scrambling on an ATM Circuit
The command to enable scrambling varies depending on the type of circuit. For a T3 ATM circuit, you must use the command atm ds3-scramble, as follows: Router2#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router2(config)#interface ATM0/0 Router2(config-if)#atm ds3-scramble Router2(config-if)#exit Router2(config)#end Router2# For E3 circuits, scrambling is actually enabled by default, but you can disable it with the no form of the comm..
