MPLS: OSPF sham-links

Introduction The provider's MPLS cloud has three routers namely - R1 (P-router), R2 (PE-R2) and R3 (PE-R3). These routers formed OSPF adjacency with one another. R2 and R3 are iBGP neighbors peering with each other's loopback address. The TTL propagation within the MPLS cloud was suppressed with no mpls ip propagate-ttl command. This is to … Continue reading MPLS: OSPF sham-links

BGP: Injecting IGP route into BGP without redistribution

The diagram is complicated with an additional link, and instead of full BGP route in AS65000, the BGP route is propagated with the help of OSPF. In previous lab, the BGP full mesh was established by peering both subnets of a BGP router. However this step can be simplified by peering the BGP speaker's loopback … Continue reading BGP: Injecting IGP route into BGP without redistribution

Web Cache Communication Protocol (WCCP)

Purpose To offset the load of edge router in http request. A http request sent by a host is redirected to local content cache engine (aka content engine), content engine will then send the content back to the requesting host. Operation Other things about WCCP 1. Only works with IPv4. 2. Has two versions. 3. … Continue reading Web Cache Communication Protocol (WCCP)

An introduction to Point-to-Point Protocol

The big picture PPP is a layer 2 WAN technology that is designed to establish connection between two nodes over a variety of network mediums. Features 1. It has built-in error detection. 2. Monitoring the quality of the link before sending frames. 3. Capability to encapsulate frames and carry them over various layer2 WAN technologies … Continue reading An introduction to Point-to-Point Protocol

Frame relay: Multilink point to point frame relay

Reference: http://www.cisco.com/en/US/docs/ios/12_2s/feature/guide/fs_mfr.html Multilink Frame Relay (FRF.16.1) 1. This technology aggregates multiple number of physical serial interfaces into one bundle. a. This provides link redundancy i.e. if a physical link of a bundle has failed, the frame relay link will still be available. b. This also provides bandwidth aggregation from multiple serial interfaces. (See http://www.cisco.com/en/US/docs/ios/12_2s/feature/guide/fs_mfr.html#wp1054102) 2. The aggregated … Continue reading Frame relay: Multilink point to point frame relay