Transmission method for control information in communication network

• US 4,875,208 A
• Filed: 01/26/1988
• Issued: 10/17/1989
• Est. Priority Date: 03/06/1987
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Furuhashi, Koshi, Furuya, Masakazu, Miyazaki, Satoshi, Kawatobi, Tatsuo, Kashio, Jiro, Kouyama, Sinichi
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Jung, Min
• Application Number:
  US07/148,532
• Time in Patent Office: 630 Days
• Field of Search: 370/94, 370/60, 370/13, 370/16, 370/54, 340/825.06, 340/825.16, 340/825.52
• US Class Current: 370/400
• 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

Herein disclosed is a communication network, in which two terminal nodes transmit and receive messages containing a destination node discriminator and a source node discriminator by way of a communication route composed of at least one relay node and a plurality of information links connecting the terminal nodes and the relay node. In this communication network, the relay node is stored in advance, in accordance with the combination of a destination node and a source node, with both the information link for transmitting the messages received and the flag information indicating the establishment of the communication route from said source node to the relay node itself. When any of the terminal nodes designates the other terminal node as the destination node and transmits the control message for the communication route establishment to the destination node, the relay node having received the control message sets the flag information, which corresponds to the combination of the source node and the destination node, in a state indicating the link establishment, and transmits said received message to said information link in case the information link corresponding to said combination is in the connected state. The relay node on the communication route transmits the control message to an adjacent node, when it detects the state change of the adjacent information link, under a condition that the flag information corresponding to said information link is in the set state.

Claims

1. A method for transmitting control information in a communication network having a plurality of nodes comprising:

a first step of sending out from a message source node a first control message including a destination node discriminator and a source node discriminator for establishing a communication route between a message destination node and the message source node to an information link determined in accordance with said destination node discriminator;

a second step of operating a relay node on said communication route having received said first control message to set route flag means corresponding to the communication route defined by the source node discriminator and destination node discriminator of said first control message, at a first state which indicates that the route from said source node to said relay node has been established, and to relay said first control message to an information link determined in accordance with said communication route; and

a third step of operating said relay node when said relay node detects that the condition of the information link connected to said relay node has changed, to send out a second control message for informing an adjacent node of the change in condition of said communication route detected by the relay node if said route flag means corresponding to the communication route composed partially of said information link indicates said first state.

2. A method of transmitting control information in a communication network having a plurality of nodes comprising:

a first step of sending out from a message source node a first control message including a destination node discriminator and a source node discriminator for establishing a communication route between a message destination node and the message source node to an information link determined in accordance with said destination node discriminator;

a second step of operating a relay node on said communication route having received said first control message to set route flag means corresponding to the communication route defined by the source node discriminator and destination node discriminator of said first control message, at a first state which indicates that the route from said source node to said relay node has been established, and to relay said first control message to an information link determined in accordance with said communication route; and

a third step of operating said relay node to change the state of route flag means, when said relay node receives from an information link at the side of the source node a second control message indicating a disconnection of said communication route, to a second state which indicates that the communication route from said source node to said relay node has been disconnected, and to relay said second control message to an information link composing a part of destination node side of said communication route.

3. A method of transmitting control information in a communication newwork having a plurality of nodes connected to one another through information links, comprising:

a first step of operating a message source node to send out a first control message containing a destination node discriminator and a source node discriminator for establishing a communication route with a message destination node to one information link determined in accordance with said destination node discriminator;

a second step of operating a relay node on said communication route having received said first control message to set route flag means prepared to correspond to the communication route defined by the source node discriminator and the destination node discriminator of said first control message, at a first state which indicates that the route from said source node to said relay node has been established, and to relay said first control message received by said relay node to an information link determined in accordance with said communication route;

a third step of operating said relay node to change the state of said route flag means, when it receives from an information link at the side of said source node a second control message indicating the disconnection of said communication route, to a second state which indicates that the communication route from said source node to said relay node has been disconnected, and to relay said second control message to an information link determined by a destination node discriminator of said second control message; and

a fourth step of operating said relay node to refer, when said relay node detects that the condition of the information link connected to said relay node has changed, to said route flag means corresponding to the communication route composed partially of said information link, in order to judge whether or not a third control message for informing an adjacent node of the change in condition of said communication route detected by the relay node is to be sent out by itself.

4. A control information transmitting method according to claim 3, wherein said relay node includes link flag means for indicating the state of each of a plurality of information links connected to said relay node, and wherein said relay node transmits each of said control messages in accordance with the state of the link flag means corresponding to the information link.

5. A control information transmitting method according to claim 3, wherein said relay node refers to the route flag means corresponding to the communication route containing said information link at its upstream side if during, said fourth step the information link changes from its connect state to its disconnect state, and transmits the third control message to indicate the disconnection of said route to the information link at the downstream side of said communication route if said route flag is in the first state.

6. A control information transmitting method according to claim 3, wherein said relay node refers to the route flag means corresponding to the communication route containing said information link at its upstream side if during, said fourth step it is determined that the information link has changed from its disconnect state to its connect state, and transmits said third control message for establishing said route to said information link if said route flag is in its first state.

7. A communication network including a plurality of nodes connected through information links for establishing a communication route between two communicating nodes which includes a relay node positioned in said communication route comprising:

a plurality of interface means connected to different information links, respectively, for receiving messages from said information links, transmitting messages to said information links and detecting the connections of said information links;

selection means connected to said interfaces for selecting the information link to transmit said messages in accordance with the destinations of the received messages;

table means for storing route flags indicating whether or not the routes from the source node to the destination nodes of said messages have been established, for each communication route defined by said source nodes and said destination nodes; and

control means coupled to both said plurality of interface means and said selection means, respectively, for rewriting said route flags corresponding said communication routes selectively, when one of said interface means receives the control message for establishing or disconnecting said communication route from an adjacent node, and for transmitting the control messages for notifying said adjacent node of the state changes of said information links in accordance with the state of the route flag corresponding to the communication route composed partially of one of said information links when any of said interface means detects the state changes of one of said information links.