route and relay traffic through a series of routers. Routers Chapter 6 Local Area Networking are protocol sensitive, SO the more internetworking protocols they support, the more complex the software and the greater the number of routing tables and algorithms required to support those protocols. IP Switches The network core is responsible for providing interconnectivity, server access, and network management to the edge devices on the network periphery. At the edge of a LAN, a shortage of network capacity, coupled with proliferation of broadcasts and multicasts, can create significant network problems. When the edge demand exceeds the capacity of the core, buffer overruns create capacity overload and lead to lost packets, reducing the availability and reliability of the network. As a result, users today suffer from congestion, inadequate server access, and slow response times. (But to be truthful, this is often a symptom of poor design and planning rather than technological inferiority.) People want to see information in a matter of a few seconds, so these problems are increasingly frustrating. The solution to the problem of these increases in traffic in the core and at the edge is the IP switch. The IP switch was designed to speed up choked networks. IP switches replace the slower, more processing-intensive routers. Routers, in general, are slower than switches because they must examine multiple packet fields, make substitutions in the packet headers, and then compute the routes on a packet-by- packet basis. All this activity introduces congestion and latency. The idea behind IP switching is to make what is essentially a connectionless data technology behave like the more reliable circuit-switched network. The goal is to make networks- intranets, extranets, and the Internet-faster, as well as to enable the deployment of new genres of applications, including voice, video, and other streaming traffic. IP switching has two major objectives. One is to add quality of service (QoS) support to IP. (QoS is discussed in d