GRE tunneling can be used to encapsulate Multicast traffic. This could be useful for; An advantage of GRE tunneling relative to IPsec tunneling is that GRE can offer finer-grained QoS because routers have visibility into the IP packet header Tunnel Multicast traffic over unicast only networks GRE …

MSDP describes a mechanism to connect multiple PM-SM domains together. Each PM-SM domains uses its own RP and does not have to depend on RP in other domains. This topic has been boken down into the following; MSDP MSDP to an Anycast Rendezvous Point

Using Anycast RP within PIM-SM domains is an implementation strategy that provides RP redundancy, rapid RP failover and RP load sharing Anycast RP allows two or more RPs to share the load for source registration and the ability to act as hot backup routers for each other MSDP is the key protocol in …

Multicast Source Discovery Protocol (MSDP); MSDP has been designed for interdomain usage Creates a web of communicating RPs to exchange information about active multicast sources Each RP knows about the sources that are registered to it and this information is flooded to all MDSP peers using …

LDP esstablishes a session in 2 steps; hello messages peridically sent on all MPLS-enabled interfaces MPLS enabled routers respond to received hello messages by attampting to esstablish a session with teh source of the hello message LDP link hello is UDP sent to “all routers on this subnet” …

RFC1771 – you have control only over your AS, you cannt tell other AS how to route traffic passing through (attributes). Neighbor relationship; Neighbors start in IDLE 1st Stage: ACTIVE 2nd Stage: OPEN SENT 3rd Stage: OPEN CONFIRMED 4th Stage: ESSTABLISHED Hello messages sent every 60 sec and …

BGP process in MPLS VPN; Global BGP routes (Internet routing) are exchanges as in traditional BGP setup VPNv4 Prefixes are exchanged through MP-BGP VPN routes are exchanged with CE routers through per-VRF External BGP sessions Configuring; (config)# router bgp (config-router)# address-family vpn4 …

VRF Configuration tasks; Create a VRF table Assign RD to the VRF Specify export and import route targets (optional) Configure a VPN ID Assign interfaces to VRFs Commands; (config)# ip vrf <name> (config-vrf)# rd route-distinguisher - can be 16 bit AS number: 32 bit decimal no OR 32 bit IP:16 …

Mandatory Enable CEF switching Configure LDP on every label-enabled interface Optional Configure MPLS ID Configure MTU size for labelled packets Configure IP TTL propagation Configure conditional label advertising Config mpls ldp router-id interface [force] router(config-if)# mpls ip …

IP aggregation/sumerisation breaks an LSP into 2 segments Aggregation should not be used where end-to-end LSP’s are required such as witin; MPLS VPNs MPLS TE MPLS enabled ATM network Transit BGP where core routers are not running BGP Label allocatation and distribution in a frame-mode MPLS network …