Setting Up Multicast Networking
There are three steps to setting up IP multicast routing on a Cisco router: Step 1. Enable multicast routing Step 2. Turn on PIM in appropriate mode on selected interfaces Step 3. Set up rendezvous points (RPs) The following sections describe each step in greater detail.’
Summary of Rules for Routes Advertised in BGP Updates
The following list summarizes the rules dictating which routes a BGP router sends in its Update messages: ■ Send only the best route listed in the BGP table. ■ To iBGP neighbors, do not advertise paths learned from other iBGP neighbors. ■ To eBGP neighbors, do not advertise paths for which the neighbor’s AS is already in the AS_PATH PA. ■ Do not advertise suppressed or dampened routes. ■ Do not advertise routes filtered via configuration. The first two rules..
Case Study: Virtual Private Networks in SuperCom Service Provider Network
As with all complex topics, the MPLS/VPN concepts are best explained through use of a case study. Imagine a service provider (let’s call it SuperCom) that is offering VPN services based on MPLS/VPN technologies. The service provider has two points of presence (POP), a U.S. POP in the San Jose area and a French POP in the Paris area. The POPs are linked through a core router located in Washington, D.C. The service provider has two customers: FastFood, with headquarters in Sa..
For very large networks, it is quite common to have a large number of areas. It also is not uncommon to have low-end routers in these areas. Therefore, receiving a large amount of summary LSA data is a cause for concern. As a solution, OSPF created the totally stubby area. As with a stub area, external LSAs are not advertised in a totally stubby area; unlike a stub area, however, a totally stubby area does not pass interarea traffic. Now, even summary link state..
When CB Policing re-marks packets instead of discarding them, the design might call for marking more than one field in a packet. For instance, when transmitting into a Frame Relay cloud, it might be useful to mark both DSCP and FR DE when a packet violates the contract. Marking multiple fields in the same packet with CB Policing is called multi-action policing. The police command uses a slightly different syntax to implement multi-action policing. By omitting the actions fro..
