Communication network, path setting method, network management system and node

Abstract

A hierarchized path setting system in a communication network efficiently contains lower order paths in higher order path. The communication network has a plurality of nodes capable to perform switching process and demultiplexing process not only for lower order paths in a predetermined hierarchical level among hierarchized paths but also for higher order paths in a hierarchical level higher than the predetermined hierarchical level, and a plurality of links connecting these nodes. The system is responsive to a new path setting demand for setting the lower order path, for setting the lower order path in the higher order path when a single higher order path is set from a predetermined transmitter node group, in which a transmitter node of the lower order path belongs, to a predetermined receiver node group including a receiver node.

1 . A communication network comprising:
 a plurality of nodes capable to perform switching process and demultiplexing process not only for predetermined order paths in a predetermined hierarchical level (hereinafter referred to lower order path) among hierarchized paths but also for higher order paths in a hierarchical level higher than said predetermined hierarchical level;   a plurality of links connecting these nodes; and   path setting control means responsive to a new path setting demand for setting the lower order path, said path setting control means setting the higher order path between said transmitter node group consisted of the nodes reachable from said transmitter node via said higher order path and said receiver node group consisted of the nodes reachable from said receiver node when the single higher order path is not set between said transmitter node of said lower order path and the receiver node, and setting said lower order path via the set higher order path and the node containing in said transmitter node group and said receiver node group.   
   
   
       2 . A path setting method in a communication system comprising:
 a plurality of nodes capable to perform switching process and demultiplexing process not only for predetermined order paths in a predetermined hierarchical level (hereinafter referred to lower order path) among hierarchized paths but also for higher order paths in a hierarchical level higher than said predetermined hierarchical level; and   a plurality of links connecting these nodes;   said path setting method comprising:   path setting control step to be activated in responsive to a new path setting demand for setting the lower order path, in said path setting control step, step, the higher order path being set between said transmitter node group consisted of the nodes reachable from said transmitter node via said higher order path and said receiver node group consisted of the nodes reachable from said receiver node when the single higher order path is not set between said transmitter node of said lower order path and the receiver node, and said lower order path being set via the set higher order path and the node containing in said transmitter node group and said receiver node group.   
   
   
       3 . A path setting method as set forth in  claim 2 , wherein in said path setting control step, a database is provided for storing reachable path information indicative of a route through which each node belonging in said transmitter node group is reachable to said receiver node group or said receiver node via the higher order path, and path setting control is performed with reference to the information in said database. 
   
   
       4 . A node comprising:
 a switch for switching not only predetermined order paths in a predetermined hierarchical level (hereinafter referred to lower order path) among hierarchized paths but also higher order paths in a hierarchical level higher than said predetermined hierarchical level;   multiplexing means for multiplexing a plurality of said lower order paths in said higher order path;   demultiplexing means for demultiplexing said higher order path into said lower order paths; and   path setting control means responsive to a new path setting demand for setting the lower order path, said path setting control means setting the higher order path between said transmitter node group consisted of the nodes reachable from said transmitter node via said higher order path and said receiver node group consisted of the nodes reachable from said receiver node when the single higher order path is not set between said transmitter node of said lower order path and the receiver node, and setting said lower order path via the set higher order path and the node containing in said transmitter node group and said receiver node group.   
   
   
       5 . A network management system in a communication network including a plurality of nodes capable to perform switching process and demultiplexing process not only for predetermined order paths in a predetermined hierarchical level (hereinafter referred to lower order path) among hierarchized paths but also for higher order paths in a hierarchical level higher than said predetermined hierarchical level, and a plurality of links connecting these nodes;
 said network management system comprising:   path setting control means responsive to a new path setting demand for setting the lower order path, said path setting control means setting the higher order path between said transmitter node group consisted of the nodes reachable from said transmitter node via said higher order path and said receiver node group consisted of the nodes reachable from said receiver node when the single higher order path is not set between said transmitter node of said lower order path and the receiver node, and setting said lower order path via the set higher order path and the node containing in said transmitter node group and said receiver node group.   
   
   
       6 . A network management system as set forth in  claim 5 , wherein said path setting control means has a database storing reachable path information indicative of a route through which each node belonging in said transmitter node group is reachable to said receiver node group or said receiver node via the higher order path, and performs path setting control with reference to the information in said database. 
   
   
       7 . A storage medium storing a program to be executed by a computer for path setting control in a communication network comprising:
 a plurality of nodes capable to perform switching process and demultiplexing process not only for predetermined order paths in a predetermined hierarchical level among (hereinafter referred to lower order path) hierarchized paths but also for higher order paths in a hierarchical level higher than said predetermined hierarchical level; and   a plurality of links connecting these nodes;   said program comprising:   path setting control step to be activated in responsive to a new path setting demand for setting the lower order path, in said path setting control step, in said path setting control step, the higher order path being set between said transmitter node group consisted of the nodes reachable from said transmitter node via said higher order path and said receiver node group consisted of the nodes reachable from said receiver node when the single higher order path is not set between said transmitter node of said lower order path and the receiver node, and said lower order path being set via the set higher order path and the node containing in said transmitter node group and said receiver node group.