Path routing system for communication network

• US 5,343,466 A
• Filed: 02/19/1993
• Issued: 08/30/1994
• Est. Priority Date: 02/21/1992
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Kawamura, Hajime
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Jung, Min
• Application Number:
  US08/020,332
• Time in Patent Office: 557 Days
• Field of Search: 370/54, 370/60, 370/94.1, 370/58.1, 370/58.2, 370/58.3
• US Class Current: 370/238
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/26 Route discovery packet

Abstract

In a path routing system for a communication network having a plurality of nodes and a plurality of transmission lines, an originate node transmits a routing message with a transmission line attribute designation to a bypass node for establishing a path between the originate node and a terminal node. A repeater node searches for a transmission line having the same attribute as the transmission line attribute designation upon receipt of the routing message with the transmission line attribute designation, and transmits the message to an adjacent node through the searched transmission line. A path between the originate node and the terminal node is autonomously selected to pass through transmission lines having the desired attribute by repeatably searching the transmission lines and transmitting the message between nodes disposed between the originate node and the terminal node.

Claims

1. A path routing system for a communication network comprising a plurality of nodes and a plurality of transmission lines, said path routing system comprising:

an originate node including means for transmitting a routing message with a transmission line attribute designation to a bypass node for establishing a path between said originate node and a terminal node;

a repeater node including means for searching for a transmission line having the same attribute as said transmission line attribute designation upon receipt of said routing message with the transmission line attribute designation, and means for transmitting said message to an adjacent node through the searched transmission line,

whereby, a path from said originate node to said terminal node is autonomously selected to pass through transmission lines having the desired attribute by repeatably searching the transmission lines and transmitting the message between nodes disposed between said originate node and said terminal node.

2. A path routing system as set forth in claim 1, wherein the node in receipt of said routing message with the transmission line attribute designation searches for a vacant transmission line having the same attribute as said transmission line attribute designation.

3. A path routing system for a communication network including a plurality of nodes and a plurality of transmission lines, in which each node comprises a multiplexer for multiplexing multi-media information, wherein said multiplexer comprises:

means for transmitting a routing message with a transmission line attribute designation for establishing a path in said communication network;

a transmission line attribute table preliminarily storing attributes of transmission lines, including at least the attributes of the transmission lines between the own node and an adjacent node;

searching means for searching for a transmission line having the same attribute as said transmission line attribute designation on the basis of the content of said transmission line attribute table; and

message transmitting means for transmitting said routing message with said transmission line attribute designation to an adjacent node according to the result of the search of said searching means.

4. A path routing system as set forth in claim 3, which further comprises:

judgement means for making a judgement as to whether the transmission line searched by said searching means has a vacant band; and

means for controlling transmission of said routing message with said transmission line attribute designation to the adjacent node on the basis of the result of the judgement made by said judgement means. PG,26

5. A path routing system as set forth in claim 3, which further comprises:

judgement means for making a judgement as to whether said routing message with said transmission line attribute designation is already received; and

means for controlling said searching means for terminating searching when said judgement means judges that said routing message with said transmission line attribute designation is already received.

6. A path routing system as set forth in claim 3, which further comprises:

judgement means for making a judgement as to whether the own node is designated as a terminal node on the basis of said routing message with said transmission line attribute designation; and

means for controlling said searching means for terminating the search of the transmission line when a judgement is made that the own node is the terminal node.

7. A path routing system as set forth in claim 3, which further comprises:

judgement means for making a judgement as to whether a number of repeater nodes passed before reaching the own node meets a predetermined maximum repeater node number on the basis of said routing message with the transmission line attribute designation; and

means for controlling said searching means for terminating the search for the transmission line when a judgement is made that the number of repeater nodes reaches the maximum number.

8. A path routing system as set forth in claim 3, wherein said multiplexer of an originate node further includes:

means for adding a hop count indicative of an available number of repeater nodes for connection, representing a maximum number of the repeater nodes in the path;

and said multiplexers of each repeater node further include;

means for decrementing said hop count in said routing message with said transmission line attribute designation and adding the updated hop count to said routing message with said transmission line attribute designation;

means for determining whether the hop count provided in said routing message with the transmission line attribute designation is zero; and

means for controlling said searching means for terminating the search when a determination is made that the hop count is zero.

9. In a communication network for communication between a plurality of nodes through a plurality of transmission lines respectively having various, mutually distinct attributes, in which a communication path is established between a first node as an originate node and a second node as a desired terminal node for communication therebetween, a path routing system comprising:

first means incorporated in each node for generating a request message for establishing a path to said second node, said request message including designated attribute information identifying a desired attribute of a transmission line to be used for establishing said communication path;

second means incorporated in each node for preliminarily storing attribute information of said transmission lines connecting the node to at least one adjacent node;

third means incorporated in each node and responsive to said request message received from an upstream side adjacent node in terms of the path to be established, for searching an available transmission line having the attribute matching the designated attribute for establishing said path on the basis of said designated attribute information included in said request message and said stored attribute information; and

fourth means incorporated in each node for transmitting said request message to a downstream side adjacent node through the searched available transmission line.

10. A path routing system as set forth in claim 9, which further comprises a fifth means incorporated in each node for storing the status of each transmission line disposed between a node and its at least one adjacent node, and said third means checks the availability of each transmission line in terms of an assignment of a time slot in addition to a matching of an attribute to the designated attribute.

11. A path routing system as set forth in claim 10, wherein said request message further includes a repeater node count indicative of a number of repeater nodes included in the upstream side routed path, and said path routing system further comprises sixth means for checking whether said repeater node count reaches a predetermined allowable maximum number of repeater nodes to be disposed in the path to be established between said first and second nodes and disabling said third means to terminate routing when said allowable maximum number is reached.

12. A path routing system as set forth in claim 11, which further comprises seventh means incorporated in each node for checking whether the own node is said second node and disabling said third means to terminate routing when the own node is said second node.