Computing forward and reverse paths and checking the liveness thereof
Systems and methods for computing forward and reverse paths and checking the liveness, keep-alive status, or continuity of the forward and reverse paths are provided. A method ( 90 ), according to one implementation, includes the step of creating ( 92 ) one or more messages related to a computation of a forward path from a head-end node ( 12, 32 ) to a tail-end node ( 14, 34 ) and a computation of a reverse path from the tail-end node ( 14, 34 ) to the head-end node ( 12, 32 ). The method ( 0 ) also includes the step of adding ( 94 ) a data object to the one or more messages, the data object including an intent to check the liveness of the forward path and reverse path.
1 . A method comprising steps of:
responsive to a request for path computation and an intent to perform a liveliness check of a forward path and a reverse path subsequent to the path computation, including a data object in a path computation message where the data object includes details to program the liveliness check on the forward path and the reverse path, wherein the liveliness check utilizes Seamless BFD (S-BFD), wherein the data object comprises an S-BFD object and includes one or more discriminator values for identifying at least a head-end node and a tail-end node for the liveliness check; and
transmitting the path computation message with the data object included therein, wherein the liveliness check is stateless at the tail-end node.
2 . The method of claim 1 , wherein the request is initiated by a head-end node with the transmitting to a Path Computation Element (PCE), and the steps further include the PCE
subsequent to the path computation, transmitting path computation messages to the head-end node and a tail-end node with additional data objects to set up the liveliness check on the forward path and the reverse path.
3 . The method of claim 1 , wherein the transmitting is by a Path Computation Element (PCE), and the steps further include
transmitting the path computation message with the data object to both a head-end node and a tail-end node to set up the liveliness check on the forward path and the reverse path.
4 . The method of claim 1 , wherein the steps further include
utilizing the data object to program the liveliness check at a head-end node and a tail-end node.
5 . The method of claim 1 , wherein the path computation message is a Path Computation Element Protocol (PCEP) message.
6 . The method of claim 1 , wherein the path computation message is a request for a new path.
7 . The method of claim 1 , wherein the path computation message is an update message for an existing path.
8 . The method of claim 1 , wherein the data object defines a transport type of the reverse path.
9 . The method of claim 1 , wherein the data object defines a transport type of the reverse path that is different from a transport type of the forward path.
10 . The method of claim 1 , wherein the data object includes discriminator values for the liveliness check.
11 . An apparatus comprising:
one or more processors, a network interface, and memory storing instructions that, when executed by the one or more processors, cause the one or more processors to
responsive to a request for path computation and an intent to perform a liveliness check of a forward path and a reverse path subsequent to the path computation, include a data object in a path computation message where the data object includes details to program the liveliness check on the forward path and the reverse path, wherein the liveliness check utilizes Seamless BFD (S-BFD), wherein the data object comprises an S-BFD object and includes one or more discriminator values for identifying at least a head-end node and a tail-end node for the liveliness check; and
transmit the path computation message with the data object included therein, wherein the liveliness check is stateless at the tail-end node.
12 . The apparatus of claim 11 , wherein the apparatus is a head-end node with the path computation message transmitted to a Path Computation Element (PCE) such that, subsequent to the path computation, the PCE transmits path computation messages to the head-end node and a tail-end node with additional data objects to set up the liveliness check on the forward path and the reverse path.
13 . The apparatus of claim 11 , wherein the apparatus is a Path Computation Element (PCE), and the instructions are further configured to
transmit the path computation message with the data object to both a head-end node and a tail-end node to set up the liveliness check on the forward path and the reverse path.
14 . The apparatus of claim 11 , wherein the data object is utilized to program the liveliness check at a head-end node and a tail-end node.
15 . The apparatus of claim 11 , wherein the path computation message is a Path Computation Element Protocol (PCEP) message.
16 . The apparatus of claim 11 , wherein the path computation message is a request for a new path.
17 . The apparatus of claim 11 , wherein the path computation message is an update message for an existing path.
18 . The apparatus of claim 11 , wherein the data object defines a transport type of the reverse path.
19 . The apparatus of claim 11 , wherein the data object defines a transport type of the reverse path that is different from a transport type of the forward path.
20 . The apparatus of claim 11 , wherein the data object includes discriminator values for the liveliness check.