Protocol Filtering and Controlling LAN Floods
Attackers can cause broadcast floods to disrupt communications over the LAN. You saw an example of this in the section "MAC Address Floods and Port Security." Therefore, it is important to control flooding on the switches. There are two main ways to do this: Set up threshold limits for broadcast/multicast traffic on ports Use protocol filtering to limit broadcasts/multicasts for certain protocols Catalyst switches allow thresholds for broadcast traffic to be set up on a pe..
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..
MPLS Traffic Engineering with Autoroute
This recipe uses Cisco's Autoroute feature for managing Traffic Engineering (TE) with OSPF in an MPLS network. For this method, we must explicitly define all of the traffic paths and associate them with Tunnels on the PE routers: Router-PE1#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Router-PE1(config)#mpls traffic-eng tunnels Router-PE1(config)#interface Loopback0 Router-PE1(config-if)#ip address 10.0.0.2 255.255.255.255 Router..
hoosing Where to Summarize Routes
EIGRP supports route summarization at any router, unlike OSPF, which requires that summarization be performed only at area border routers (ABR) or autonomous system border routers (ASBR). EIGRP’s flexibility helps when designing the internetwork, but it also poses some questions as to where to summarize EIGRP routes. In some cases, the options are relatively obvious. For example, consider the 10.17.32.0/19 address block in manufacturing in Figure 1-1. The manufacturing divi..
