Abilene[] is another project of UCAID. It's complementary to Internet2 in the sense that the main goal of Abilene is to provide a primary backbone network for the Internet2 project. UCAID, in partnership with Qwest Communications, Nortel Networks, and Cisco Systems, has developed the Abilene network. Abilene provides the high-performance interconnect services among the Internet2 regional aggregation points. The primarily OC48c (2.5 Gbps) POS (Packet Over SONET) Abilene netw..
Interdomain Multicast: MSDP and MBGP
How do RPs learn about sources in other PIM domains? This problem is solved by the Multicast Source Discovery Protocol (MSDP). At the time of this writing, MSDP was still an Internet draft, and therefore this section describes only a work-in-progress. MSDP uses simple, one-to-one, BGP-like peering sessions to establish communication between RPs. Unlike BGP, however, no connection collision mechanism exists. Instead, the peer with the higher address listens on TCP port..
External BGP (EBGP) neighbors are usually directly connected. In Figure 8-13, you configure EBGP between Routers A and B and investigate the operation and configuration of EBGP neighbors. Figure 8-13. Configuring EBGP The first step in configuring EBGP is to configure a loopback interface on Routers A and B. (See Example 8-2.) As with OSPF, the IP address assigned to the loopback interface is used as the BGP router ID. Example 8-2. Configuring Loopback Interfaces on Routers..
Interframe Spaces, shown in Figure 11-3, allow 802.11 to control which traffic gets first access to the channel when carrier sense declares the channel to be free. Figure 11-3. IEEE 802.11 DCF Interframe Spaces [View full size image] 802.11 currently defines three interframe spaces: • Short interframe spaces (SIFS), which are 10 long • Point interframe spaces (PIFS), which are 30 long (SIFS + 1 [20 ] slot time..
Use the ntp authentication command to authenticate NTP traffic between associations. To configure an NTP enabled router to require authentication when other devices connect to it, use the following commands: Router1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router1(config)#ntp authentication-key 2 md5 oreilly Router1(config)#ntp authenticate Router1(config)#ntp trusted-key 2 Router1(config)#end Router1# Then you must configure th..
