Data transmission installation of the radio network type, and corresponding method

• US 6,023,457 A
• Filed: 11/07/1997
• Issued: 02/08/2000
• Est. Priority Date: 04/02/1992
• Status: Expired due to Term

• Current Assignee: MOSAID Technologies Inc. (f/k/a Conversant Intellectual Property Management)
• Original Assignee: Inria Institut National de Recherche EN Informatique et EN Automatique
• Inventors: Jacquet, Philippe, Muhlethaler, Paul
• Primary Examiner(s): TON, DANG T
• Application Number:
  US08/966,016
• Time in Patent Office: 823 Days
• Field of Search: 370/310, 370/312, 370/252, 370/257, 370/346, 370/347, 370/320, 370/335, 370/342, 370/437, 370/445, 370/449, 370/451, 370/450, 370/460, 370/461, 370/463, 370/465, 370/466 , 370/467, 370/503, 370/241, 370/903, 370/351, 370/352, 370/389, 370/276, 375/205, 375/354, 375/356, 375/363, 375/364-366, 375/200, 455/13.2, 455/235.1, 455/3.2
• US Class Current: 370/276
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 40/24 Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 40/30 for proactive routing
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 84/22 with access to wired networks

Abstract

A data transmission installation includes at least two data processing tenals(Pa,Pb), each equipped with a network interface(Ia,Ib) fro transmitting messages on request, and collecting received messages, a transmission/reception management device(ARC) giving instructions confirming transmission or reception, a test unit for defining a recognized collision, and a unit for resolving collisions, following a recognized collision condition. Each of the data processing terminals includes a multi-directional radio transmission/reception device controlled in accordance with the confirming instructions fro the transmission of messages to be exchanged. In response at least to the start of an instruction confirming transmission, the radio transmission/reception device operates in rapidly alternating transmission/reception, according to a pattern chosen in order to be peculiar to the data processing terminal. The test unit is configured to recognize a collision if a signal of a level greater than a first level threshold is received during a substantial part of at least one silence in the rapidly alternating transmission/reception.

Claims

1. A data transmission installation, of a radio network type comprising at least two data processing terminals, each equipped with a network interface, said interface comprising:

a management device for the transmission and reception of messages according to a chosen protocol, and

a routing unit capable of deducing, from at least some of the received messages, which network terminals are at a symmetrical range from said routing unit, a first terminal being at a symmetrical range from a second terminal when said first and second terminals exchange messages without the intermediary of a third terminal, and capable of determining whether a received message is addressed to a local terminal comprising said network interface, and of ordering the retransmission of said received message, with a possible modification, if said received message is not addressed to the local terminal or if said received message is addressed to the local terminal and also to at least one other network terminal, where the local terminal is used as a relay terminal.

2. An installation according to claim 1, wherein each network interface further comprises a memory capable of storing at least one list of terminals that it receives and one list of terminals able to receive it.

3. An installation according to claim 2, wherein the routing unit is capable of maintaining and transmitting said list of terminals that it receives, and maintaining the list of terminals that received it, from said at least some of the received messages.

4. An installation according to claim 3, wherein the routing unit is capable of storing in a memory a local routing table establishing a correspondence between a final destination terminal and a relay terminal at a symmetrical range from said local terminal.

5. An installation according to claim 3, wherein each network interface is capable of storing information that it receives, said information being of the type such that a second terminal is received by such other third terminal.

6. An installation according to claim 5, wherein each network interface is capable of forcing an emission of artificial messages.

7. An installation according to claim 6, wherein at least some of said artificial messages emitted by a network interface are used for services, and especially for the transmission to terminal(s) stored in its local routing table, of the list of terminals that it receives and/or at least a part of the information included in its routing table.

8. An installation according to claim 6, wherein at least some of said artificial messages are used for the exchange of information useful for understanding the messages.

9. An installation according to claim 2, wherein each routing unit is also capable of storing in the memory another table forming a topological directory and comprising multiplets, each of said multiplets comprising:

a first element which is one of the symmetrical range terminals of the list of terminals that received it,

an intermediary element which is a terminal that may directly or indirectly receive it,

and a last element which is a figure indicating a number of skips that are necessary for reaching the terminal corresponding to said intermediary element, thereby allowing to determine a relay terminal at symmetrical range required for relaying a message to a chosen terminal of the network.

10. An installation according to claim 9, wherein the routing unit is capable of maintaining and modifying the multiplets of the topological directory according to said at least some of the received messages.

11. An installation according to claim 9, wherein a message to relay comprises a definition of maximum number of relay terminals.

12. An installation according to claim 2, wherein each routing unit is also capable of storing in the memory a broadcast table comprising at least a part of said terminals at symmetrical range, each terminal of said part being able to reach at least one network terminal, in view of the broadcast of a message with multiple destinations.

13. An installation according to claim 12, wherein the routing unit is capable of maintaining and modifying the broadcast table according to said at least some of the received messages.

14. An installation according to claim 1, wherein a message with multiple destinations comprises a broadcast number.

15. An installation according to claim 4, wherein each routing unit is capable of modifying at least a part of a received message, before its retransmission in view of a relay or a broadcast, according to its routing table.

16. An installation according to claim 15, wherein the message comprises:

a header including at least information designating one or more destination terminals of the message, and

a body,

wherein the modification of a received message to broadcast concerns the modification of at least a part of the destination terminal information included in its header, said information being comprised in the broadcast table.

17. An installation according to claim 15, wherein the message comprises:

a header including at least information designating the destination terminal of the message, and

a body,

wherein the modification of a message to transmit includes the addition of information relative to at least one relay terminal required for the routing of said message, said information being comprised in the routing table.

18. An installation according to claim 2, wherein the memory is rewritable and is comprised in the routing unit.