PACKET COMMUNICATION SYSTEM, COMMUNICATION METHOD AND PROGRAM

• US 20110128912A1
• Filed: 11/22/2010
• Published: 06/02/2011
• Est. Priority Date: 11/30/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Okazaki, Atsuya, Negishi, Yasushi, Katayama, Yasunao
• Granted Patent: US 8,442,028 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04J 3/0658 Clock or time synchronisation among packet nodes
• CPC Class Codes: H04L 45/40 Wormhole routing
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 40/06 based on characteristics of available antennas
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A system including multiple nodes performing radio communication, wherein each node stores routing information, uses it to determine a transmission path, and performs cut-through transmission by transmitting and receiving packets to and from a node on the determined path through transmission and reception radio waves given a directivity by controlling their phases. In the system, time synchronization and transmission and reception of packet communication records are performed during a certain time period by carrying out the cut-through transmission while controlling phases of the radio waves so that all of the nodes form one or more closed loops. The node transmits and receives packets in accordance with routing information and a time frame assigned to each of the nodes as a time when each node is allowed to transmit and receive a packet, updates the routing information, and shares it with each node.

Claims

1. A packet communication system for transferring a packet to a destination address, the system comprising:

a plurality of nodes performing radio communication, wherein each of the said nodes;

stores therein routing information for determining a transmission path of said packet,

transmits and receives said packets to a transfer destination node and from a transfer source node on a transmission path determined by use of said routing information, through transmission and reception radio waves each of which is given a certain directivity by controlling a phase of said radio wave, and

has a function of performing a cut-through transmission in which transfer of said packet to said transfer destination node is initiated after reading of a destination address included in said packet and before reception of said packet is completed, and

wherein said packet communication system;

performs time synchronization and transmission and reception of packet communication records during a certain time period by carrying out said cut-through transmission, while controlling said phases of said transmission and reception radio waves so that all of the said nodes form one or more closed loops, and

transfers said packet to said destination address at a time other than said certain time period in accordance with said routing information and a time frame assigned to each of the said nodes as a time when each said node is allowed to transmit and receive a packet, updates said routing information held by each said node on the basis of said packet communication records, and shares said updated routing information among said nodes after said time synchronization.

2. The packet communication system according to claim 1, wherein:

said node comprises an antenna formed of a plurality of antenna elements arranged in a certain order, phase control means for controlling said phases of said transmission and reception radio waves of each of the said antenna elements, and transmission and reception means for transmitting and receiving said packet through said transmission and reception radio waves, and

said phase control means converts said destination address included in said packet into a phase difference of a radio wave to be applied to each of the said antenna elements included in said transfer destination node.

3. The packet communication system according to claim 1, wherein:

said node comprises an antenna formed of a plurality of antenna elements arranged in a certain order, phase control means for controlling said phases of said transmission and reception radio waves of each of the said antenna elements, and transmission and reception means for transmitting and receiving said packet through said transmission and reception radio waves, and

said phase control means, after reading said destination address included in said packet and before reception of said packet is completed, converts said destination address included in said packet into a phase difference of a radio wave to be applied to each of the said antenna elements included in said transfer destination node.

4. The packet communication system according to claim 1, wherein said time synchronization and said transmission and reception of said packet communication records are performed at predetermined intervals.

5. The packet communication system according to claim 1, wherein said time synchronization and said transmission and reception of said packet communication records are initiated by transferring an initiation request made by one of the said plurality of nodes among said other nodes sequentially from one to another.

6. The packet communication system according to claim 1, wherein said packet communication records each include a transfer rate and a data transfer amount between said nodes.

7. The packet communication system according to claim 1, wherein each of the said nodes further stores therein address information of communicable nodes and channel information used for communication.

8. The packet communication system according to claim 1, wherein said packet communication system comprises a plurality of wireless nodes performing said radio communication and a plurality of wired nodes mutually connected via a cable.

9. A communication method in a packet communication system, including a plurality of nodes performing radio communication, for transferring a packet to a destination address, the communication method comprising:

storing, in each of the said nodes, routing information for determining a transmission path of said packet;

transmitting and receiving said packets, by each of the said nodes, to a transfer destination node and from a transfer source node on a transmission path determined by use of said routing information, through transmission and reception radio waves each of which is given a certain directivity by controlling a phase of said radio wave;

performing, by each of the said nodes, a cut-through transmission in which transfer of said packet to said transfer destination node is initiated after reading of a destination address included in said packet and before reception of said packet is completed;

performing time synchronization and transmission and reception of packet communication records during a certain time period by carrying out said cut-through transmission, while controlling said phases of said transmission and reception radio waves so that all of the said nodes form one or more closed loops;

transferring said packet to said destination address at a time other than said certain time period in accordance with said routing information and a time frame assigned to each of the said nodes as a time when each said node is allowed to transmit and receive a packet;

updating said routing information held by each said node on the basis of said packet communication records; and

sharing said updated routing information among said nodes after said time synchronization.

10. The communication method according to claim 9, wherein performing transmission and reception of packet communication records further comprises determining whether said packet communication records have been acquired from all of the nodes.

11. The communication method according to claim 9, wherein:

said node includes an antenna formed of a plurality of antenna elements arranged in a certain order, phase control means for controlling phases of said transmission and reception radio waves of each of the said antenna elements, and transmission and reception means for transmitting and receiving said packet through said transmission and reception radio waves, and

transmitting and receiving said packets further comprises converting, by said phase control means, said destination address included in said packet into a phase difference to be applied to each of the said antenna elements included in said transfer destination node.

12. The communication method according to claim 9, wherein:

said node includes an antenna formed of a plurality of antenna elements arranged in a certain order, phase control means for controlling phases of said transmission and reception radio waves of each of the said antenna elements, and transmission and reception means for transmitting and receiving said packet through said transmission and reception radio waves, and

transmitting and receiving said packets, after reading said destination address included in said packet and before reception of said packet is completed, further comprises converting, by said phase control means, said destination address included in said packet into a phase difference to be applied to each of the said antenna elements included in said transfer destination node.

13. The communication method according to claim 9, wherein performing transmission and reception of packet communication records is executed at predetermined intervals.

14. The communication method according to claim 9, wherein performing transmission and reception of packet communication records further comprises initiating said time synchronization and said transmission and reception of said packet communication records by transferring an initiation request made by one of the said plurality of nodes, among said other nodes sequentially from one to another.

15. The packet communication system according to claim 9, wherein said packet communication records each include a transfer rate and a data transfer amount between said nodes.

16. The packet communication system according to claim 9, wherein each of the said nodes further stores therein address information of communicable nodes and channel information used for communication.

17. A computer program product for executing a communication method for transferring a packet to a destination address, the program being readable by a packet communication system including a plurality of nodes performing radio communication, the computer program product comprising:

a computer readable storage medium having computer readable program code embodied therewith, the computer readable program code comprising;

computer readable program code configured to;

store in each of the said nodes routing information for determining a transmission path of a packet;

transmit and receive packets to and from a transfer destination and a transfer source node on the transmission path determined by use of said routing information, said transmission and reception being performed by controlling phases of transmission and reception radio waves and giving the radio waves a certain directivity;

perform cut-through transmission in each of the said nodes in which transfer of said packet to said transfer destination node is initiated after reading a destination address included in said packet and before reception of said packet is completed;

perform time synchronization and transmission and reception of packet communication records during a certain time period by carrying out said cut-through transmission, while controlling said phases of said transmission and reception radio waves so that all of the said nodes form one or more closed loops; and

transfer said packet to said destination address at a time other than said certain time period in accordance with said routing information and a time frame assigned to each of the said nodes as a time when each said node is allowed to transmit and receive a packet, update said routing information held by each said node on the basis of said packet communication records and share said updated routing information among said nodes after said time synchronization.

18. The computer program product according to claim 17, wherein performing transmission and reception of packet communication records further comprises said packet communication system determining whether said packet communication records have been acquired from all of the said nodes.

19. The computer program product according to claim 17, wherein:

said node includes an antenna formed of a plurality of antenna elements arranged in a certain order, phase control means for controlling phases of said transmission and reception radio waves of each of the said antenna elements, and transmission and reception means for transmitting and receiving said packet through said transmission and reception radio waves, and

transmitting and receiving said packets further comprises said packet communication system converting, by said phase control means, said destination address included in said packet into a phase difference to be applied to each of the said antenna elements included in said transfer destination node.

20. The computer program product according to claim 17, wherein:

said node includes an antenna formed of a plurality of antenna elements arranged in a certain order, phase control means for controlling phases of said transmission and reception radio waves of each of the said antenna elements, and transmission and reception means for transmitting and receiving said packet through said transmission and reception radio waves, and

transmitting and receiving said packets, after said phase control means reads said destination address included in said packet and before reception of said packet is completed, further comprises said packet communication system converting, by said phase control means, said destination address included in said packet into a phase difference to be applied to each of the said antenna elements included in said transfer destination node

21. The computer program product according to claim 17, wherein performing transmission and reception of packet communication records is executed at predetermined intervals.

22. The computer program product according to claim 17, wherein performing transmission and reception of packet communication records further comprises said packet communication system initiating said time synchronization and said transmission and reception of said packet communication records by transferring an initiation request made by one of the said plurality of nodes, among said other nodes sequentially from one to another.