Techniques for determining local repair connections
View Patent ↗Techniques for configuring a local repair connection for a protected connection including determining a path for the local repair connection. The path traversed by a local repair connection starts at a node in the path associated with the protected connection and ends at a merge point node in the path associated with the protected connection that is downstream from the start node. In one embodiment, the merge point node may even be more than two hops downstream from the start node in the path associated with the protected connection. The local repair path may include zero or more nodes that are not included in the path associated with the protected connection. Techniques are also described for optimizing the path associated with a local repair connection.
1. A method of facilitating creation of a local repair connection for a first connection, the first connection traversing an original path comprising a plurality of nodes, the method comprising:
determining a first local repair path from a point of local repair (PLR) node to a merge point (MP) node, wherein the PLR node and the MP node are in the original path and the MP node is downstream from the PLR node in the original path;
determining that the first local repair path comprises a first node that is also in the original path, where the first node is downstream from the PLR node in the first local repair path and is upstream from the MP node in the first local repair path, and wherein the first node is downstream from the PLR node in the original path;
determining a second local repair path starting at the PLR node of the first local repair path and ending at the first node; and
establishing a local repair connection using the second local repair path instead of the first local repair path.
2. The method of claim 1 wherein each node in the second local repair path is in the first local repair path.
3. The method of claim 1 wherein a total number of nodes in the first local repair path is less than a total number of nodes in the second local repair path.
4. The method of claim 1 wherein a total number of nodes that are both in the original path and second local repair path is less than a total number of nodes that are both in the original path and the first local repair path.
5. The method of claim 1 wherein the PLR node and the first node are the only nodes that are both in the original path and in the second local repair path.
6. The method of claim 1 wherein establishing the local repair connection comprises using Multi-Protocol Label Switching (MPLS) protocol to establish the local repair connection.
7. The method of claim 1 further comprising:
receiving data at the PLR node; and
forwarding, by the PLR node, the received data using the local repair connection.
8. A system comprising:
a memory configured to store information for a first connection, the first connection traversing an original path comprising a plurality of nodes; and
a processor configured, based upon the information stored in the memory, to:
determine a first local repair path from a point of local repair (PLR) node to a merge point (MP) node, wherein the PLR node and the MP node are in the original path and the MP node is downstream from the PLR node in the original path;
determine that the first local repair path comprises a first node that is also in the original path, where the first node is downstream from the PLR node in the first local repair path and is upstream from the MP node in the first local repair path, and wherein the first node is downstream from the PLR node in the original path;
determine a second local repair path starting at the PLR node of the first local repair path and ending at the first node; and
establish a local repair connection using the second local repair path instead of the first local repair path.
9. The system of claim 8 wherein each node in the second local repair path is in the first local repair path.
10. The system of claim 8 wherein a total number of nodes in the first local repair path is less than a total number of nodes in the second local repair path.
11. The system of claim 8 wherein a total number of nodes that are both in the original path and second local repair path is less than a total number of nodes that are both in the original path and the first local repair path.
12. The system of claim 8 wherein the PLR node and the first node are the only nodes that are both in the original path and in the second local repair path.
13. The system of claim 8 wherein the processor is configured to establish the local repair connection using Multi-Protocol Label Switching (MPLS) protocol.