In October 2002, RFC 3376 defined specifications for IGMPv3. IGMPv3 is a major revision of the protocol and is very complex. To use the new features of IGMPv3, last-hop routers have to be updated, host operating systems have to be modified, and applications have to be specially designed and written. Unfortunately, at the time of this writing (mid-2005), a very limited number of IGMPv3 applications are available. Therefore, this section does not examine IGMPv3 in detail; inste..
OSPF is an Interior Gateway Protocol (IGP), whereby each router belonging to a single area maintains an identical database. The routing table is constructed from the information in this database by running a Shortest Path First algorithm. The route is installed in the table by first resolving the least-cost route to the destination. OSPF routes packets are based solely on the IP destination, so there is no room for source-based routing. OSPF also uses IP multicast for updates..
When mainframe computers dominated the industry, user terminals attached either directly to ports on the computer or to a controller that gave the appearance of a direct connection. Each wire connection was dedicated to an individual terminal. Users entered data, and the terminal immediately transmitted signals to the host. Performance was driven by the horsepower in the hosts. If the host became overworked, users experienced delays in responses. Note, though, that the connec..
Creating an Encrypted Router-to-Router VPN in a GRE Tunnel
There are several steps to these configurations, but they are the same on both routers. The first step is to create an appropriate key exchange policy using ISAKMP. The following set of commands defines the policy with priority 10. When ISAKMP negotiates the security association (SA) parameters, it starts with the lowest priority and goes to the highest. The highest possible priority value is 10,000: Router1(config)#crypto isakmp policy 10 Router1(config-isakmp)#encr aes 256..
EIGRP redistribute Command Reference
First, for reference, the following lines show the generic syntax of the redistribute command when used as a router eigrp subcommand. Note that the syntax differs slightly depending on the routing protocol into which routes will be redistributed. Following that, Table 9-2 lists the options on the command with a brief description. redistribute protocol [process-id | as-number] [metric bw delay reliability load mtu ] [match {internal | nssa-external | external 1 | extern..
