TRANSMISSION CONTROL METHOD, NODE, AND NON-TRANSITORY COMPUTER-READABLE RECORDING MEDIUM

• US 20140247821A1
• Filed: 05/15/2014
• Published: 09/04/2014
• Est. Priority Date: 12/12/2011
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: KOGA, Syunsuke, Yamada, Kenji, TAKAHASHI, Yuji
• Granted Patent: US 9,730,140 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 40/125 using a measured number of retransmissions as a link metric
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 40/34 Modification of an existing route
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

Each of the nodes counts the number of other nodes located in a communication area of the node among nodes in a multi-hop network, and determines the number of times to retransmit a frame based on the counted number of the other nodes. Each of the nodes transmits a frame to a destination node, and repeats retransmission of the frame the determined number of times until receiving a response to the transmitted frame. Subsequently, each of the nodes changes a route to the destination node to another route when it does not receive the response after repeating the retransmissions the determined number of times.

Claims

1. A transmission control method executed by a node in an ad hoc network, the transmission control method comprising:

counting number of other nodes located in a communication area of the node among nodes in the ad hoc network;

determining number of times to retransmit a frame based on the counted number of the other nodes;

transmitting the frame to a destination node;

repeating retransmission of the frame the determined number of times until a response to the transmitted frame is received; and

changing a route to the destination node to another route when the response is not received after repeating the retransmissions the determined number of times.

2. The transmission control method according to claim 1, wherein the counting includes

transmitting control messages to the other nodes in the ad hoc network;

and

counting number of responses to the control messages.

3. The transmission control method according to claim 1, wherein the counting includes

receiving, from each of the other nodes in the ad hoc network, a control message including location information on each of the other nodes;

calculating a distance from the node to each of the other nodes based on the received location information and location information on the node; and

counting number of nodes for each of which the calculated distance is equal to or smaller than a predetermined value.

4. The transmission control method according to claim 1, wherein the counting includes counting number of neighboring nodes of the node from a link management storage unit in which information on the neighboring nodes is stored.

5. The transmission control method according to claim 4, wherein

the link management storage unit stores therein an evaluation value indicating quality of a communication path to the node, for each of the neighboring nodes, and

the counting includes counting number of nodes for each of which the evaluation value exceeds a threshold among the neighboring nodes stored in the link management storage unit.

6. A node comprising:

a counting unit configured to count number of other nodes located in a communication area of the node among nodes in the ad hoc network;

a determining unit configured to determine number of times to retransmit a frame based on the number of the other nodes counted by the counting unit;

a retransmitting unit configured to transmit a frame to a destination node and repeat retransmission of the frame the number of times determined by the determining unit until receiving a response to the transmitted frame; and

a route changing unit configured to change a route to the destination node to another route when the response is not received after the retransmitting unit repeats.

7. The node according to claim 6, wherein the counting unit transmits control messages to the other nodes in the ad hoc network, and counts number of responses to the control messages.

8. The node according to claim 6, wherein the counting unit receives, from each of the other nodes in the ad hoc network, a control message including location information on each of the other nodes, calculates a distance from the node to each of the other nodes based on the received location information and location information on the node, and counts number of nodes for each of which the calculated distance is equal to or smaller than a predetermined value.

9. The node according to claim 6, further comprising:

a link management storage unit configured to store therein information on neighboring nodes of the node, wherein

the counting unit counts number of the neighboring nodes by referring to the link management storage unit.

10. The node according to claim 9, wherein

the link management storage unit stores therein an evaluation value indicating quality of a communication path to the node, for each of the neighboring nodes, and

the counting unit counts number of nodes for each of which the evaluation value exceeds a threshold among the neighboring nodes stored in the link management storage unit.

11. A non-transitory computer-readable recording medium having stored therein a control program causing a computer included in an ad hoc network to execute a process comprising:

counting number of other nodes located in a communication area of the computer among nodes in the ad hoc network;

determining number of times to retransmit a frame based on the counted number of the other nodes;

transmitting the frame to a destination node;

repeating retransmission of the frame the determined number of times until a response to the transmitted frame is received; and

changing a route to the destination node to another route when the response is not received after repeating the retransmissions the determined number of times.

12. The non-transitory computer-readable recording medium according to claim 11, wherein the counting includes

transmitting control messages to the other nodes in the ad hoc network;

and

counting number of responses to the control messages.

13. The non-transitory computer-readable recording medium according to claim 11, wherein the counting includes

receiving, from each of the other nodes in the ad hoc network, a control message including location information on each of the other nodes;

calculating a distance from the computer to each of the other nodes based on the received location information and location information on the computer; and

counting number of nodes for each of which the calculated distance is equal to or smaller than a predetermined value.

14. The non-transitory computer-readable recording medium according to claim 11, wherein the counting includes counting number of neighboring nodes of the computer from a link management storage unit in which information on the neighboring nodes is stored.

15. The non-transitory computer-readable recording medium according to claim 11, wherein

the link management storage unit stores therein an evaluation value indicating quality of a communication path to the computer, for each of the neighboring nodes, and

the counting includes counting number of nodes for each of which the evaluation value exceeds a threshold among the neighboring nodes stored in the link management storage unit.