Related Documentation
- LN, SRX Series
- MPLS Traffic Engineering and Signaling Protocols Overview
- LN, MX, SRX, T Series
- Point-to-Multipoint LSP Configuration Overview
- Additional Information
- MPLS Feature Guide for Security Devices
Understanding Point-to-Multipoint LSPs
A point-to-multipoint MPLS label-switched path (LSP) is an LDP-signaled or RSVP-signaled LSP with a single source and multiple destinations. By taking advantage of the MPLS packet replication capability of the network, point-to-multipoint LSPs avoid unnecessary packet replication at the inbound (ingress) router. Packet replication takes place only when packets are forwarded to two or more different destinations requiring different network paths.
This process is illustrated in Figure 1. Device PE1 is configured with a point-to-multipoint LSP to Routers PE2, PE3, and PE4. When Device PE1 sends a packet on the point-to-multipoint LSP to Routers P1 and P2, Device P1 replicates the packet and forwards it to Routers PE2 and PE3. Device P2 sends the packet to Device PE4.
Figure 1: Point-to-Multipoint LSPs
Following are some of the properties of point-to-multipoint LSPs:
- A point-to-multipoint LSP allows you to use MPLS for point-to-multipoint data distribution. This functionality is similar to that provided by IP multicast.
- You can add and remove branch LSPs from a main point-to-multipoint LSP without disrupting traffic. The unaffected parts of the point-to-multipoint LSP continue to function normally.
- You can configure a node to be both a transit and an outbound (egress) router for different branch LSPs of the same point-to-multipoint LSP.
- You can enable link protection on a point-to-multipoint LSP. Link protection can provide a bypass LSP for each of the branch LSPs that make up the point-to-multipoint LSP. If any primary paths fail, traffic can be quickly switched to the bypass.
- You can configure subpaths either statically or dynamically.
- You can enable graceful restart on point-to-multipoint LSPs.
Related Documentation
- LN, SRX Series
- MPLS Traffic Engineering and Signaling Protocols Overview
- LN, MX, SRX, T Series
- Point-to-Multipoint LSP Configuration Overview
- Additional Information
- MPLS Feature Guide for Security Devices
Modified: 2013-06-10
Related Documentation
- LN, SRX Series
- MPLS Traffic Engineering and Signaling Protocols Overview
- LN, MX, SRX, T Series
- Point-to-Multipoint LSP Configuration Overview
- Additional Information
- MPLS Feature Guide for Security Devices
