SPB-PIM Gateway Node

The Gateway Selection Agent (Agent) resides in the Gateway BEB Node in the SPB network. The Gateway BEB has connections into the foreign network over SPB-PIM Gateway Interfaces. The Agent receives foreign network source information from the Controller BEB or the Controller BCB Node. The source information consists of the following components:

• Sender IP address (S)

• Group IP address (G)

• VSN identifier (I-SID)

• Gateway assigned to the stream

The Agent interacts with SPB-PIM Gateway interface and creates the multicast path. The Agent receives foreign source information from the Controller and creates a foreign source address (SA) cache after validating the reachability to S. The Agent interacts with the SPB-PIM Gateway interface to validate that the next-hop ip address toward the source is a valid PIM adjacency. The foreign SA cache includes the following components:

• Source IP address (information received from the Gateway Controller)

• Group IP address (information received from the Gateway Controller)

• Ingress port (The port through which S is accessible)

• Upstream IP address (The next-hop IP address, which is also the PIM neighbor across the SPB-PIM Gateway interface which is used to reach S as indicated by the unicast routing entry)

• Ingress VLAN ID

If multiple next-hops are available, then the first valid PIM neighbor next-hop is used for the upstream.

The SPB-PIM Gateway interface provides inter-domain multicast services. The SPB-PIM Gateway interface connects senders and receivers of multicast streams across a PIM Domain and a SPB network boundary over a Gateway interface. The SPB-PIM Gateway interface provides the following functionality:

• PIM HELLO exchanges

• Issuing Joins and Leaves

• Process received Joins and Leaves

• Implements the Gateway assignment table by acting as the Ingress BEB for streams for which the SPB-PIM Gateway interface is the selected Gateway

• Enforces the Gateway assignment table and does not forward streams for which the SPB-PIM Gateway interface is not the selected Gateway

• Forwards local and remote SPB streams to satisfy stream requests from neighboring multicast domains

• SPB-PIM Gateway Interfaces supports both SM and SSM multicast group range joins and prunes. *G joins are only supported in SM group range.

The PIM Gateway interface resides in the SPB-PIM Gateway Node (Gateway). The SPB-PIM Gateway interface connects to a PIM router in a PIM network or to another Gateway BEB in an SPB network. Local hosts (IGMP member hosts and multicast data source hosts) are not supported on SPB-PIM Gateway interfaces, only PIM Routers or another SPB BEB with SPB-PIM Gateway interface configured. Multicast data from local source hosts and IGMP reports from local hosts are dropped. An SPB Node must be configured as a SPB-PIM Gateway Node if the SPB Node is connected to a foreign PIM network or a foreign SPB network. A single Gateway Node can have multiple SPB-PIM Gateway interfaces. The SPB-PIM Gateway interface can be a VLAN or a brouter port, can reside on an MLT and is fully virtualized. The SPB-PIM Gateway interface is a translation mechanism between the PIM protocol and SPB TLVs. The SPB-PIM Gateway interface communicates with the PIM router through the standard PIM protocol messaging HELLO, JOIN, and PRUNE. The SPB-PIM Gateway interface then forms a normal PIM adjacency with the PIM router or another SPB Gateway Node. The SPB-PIM Gateway Interface processes received SG joins and prunes, *G joins and prunes, and SG-RPT joins and prunes. The SPB-PIM Gateway interface transmits SG joins and prunes, but never *G joins.The SPB-PIM Gateway Interface does not have RP capabilities, and therefore has no need for group-to-RP mapping configurations. A *G JOIN received on a SPB-PIM Gateway Interface is accepted if the destination IP is the IP address of the interface or of a neighbor on the interface if the neighbor is learned on another port in the interface. However, the RP address within the *G JOIN message is ignored by the SPB-PIM Gateway Interface.