Resource reservation in a wireless network with distributed medium access control

• US 20070002821A1
• Filed: 08/21/2003
• Published: 01/04/2007
• Est. Priority Date: 08/21/2003
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Prehofer, Christian, Karl, Holger, Carlson, Emma
• Granted Patent: US 7,693,122 B2
• Time in Patent Office: Days
• US Class Current: 370/349
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements
• CPC Class Codes: H04L 67/62 Establishing a time schedule for servicing the requests
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 28/26 Resource reservation
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A wireless network with distributed medium access control allows establishing of a virtual channel between a source node and a destination node via at least one intermediate node. The virtual channel may be established for the entire duration of a communication between the source node and the destination node, and, to establish the virtual channel, a request handler can transmit a virtual channel request, requesting an allocation of transmission resources for the virtual channel. Based on the virtual channel request, a virtual channel confirmation can be generated by the destination node and can be returned to the source node, indicating an allocation of the resources for the virtual channel. A communication handler can then transmit data from the source node to the destination node using the available transmission resources.

Claims

1-37. -37. (canceled)

38. A method of virtual channel reservation in a wireless network with distributed medium access control, including:

transmitting, from a source node, a virtual channel request over a transmission path including at least one intermediate node to a destination node, the virtual channel request requesting an allocation of transmission resources for a virtual channel from the source node through the at least one intermediate node to the destination node;

receiving a virtual channel confirmation from the destination node, the virtual channel confirmation indicating an allocation of the resources for the virtual channel; and

transmitting data from the source node to the destination node using the allocated transmission resources.

39. A method of claim 38, wherein the transmission resources include at least one of a repeating time period for transmission, a transmission frequency and a transmission code.

40. A method of claim 38, wherein the virtual channel request includes reservation information on at least one of the duration of the time period, a repetition of a time period and a time reference.

41. A method of claim 38, wherein reservation information is transmitted in association with messages or data packets according to a communication protocol, particularly according to the IEEE 802.11 standard.

42. A method of claim 38, wherein the source node or an intermediate node listens to signaling between other nodes of the wireless network to determine unreserved transmission resources in the wireless network.

43. A method of claim 42, wherein the virtual channel request requests establishment of the virtual channel using the determined unreserved transmission resources.

44. A method of claim 38, wherein the source node or an intermediate node analyses virtual channel requests or data packets including reservation information of other nodes, or analyzes release messages, to determine at least one of unreserved time periods, a transmission frequency and a transmission code.

45. A method of claim 38, wherein the virtual channel request requests the at least one intermediate node and the destination node to determine transmission resources for the virtual channel and to reserve the transmission resources, if available.

46. A method of claim 45, wherein each of the at least one intermediate node and the destination node, if available transmission capacity during the repeating time period is not available, determine alternate available transmission capacity during an alternate repeating time period.

47. A method of claim 45, wherein each of the at least one intermediate node and the destination node calculate individual time delays associated with a transmission using the alternate available transmission capacity and report same to the source node.

48. A method of claim 38, wherein the source node determines a total time delay for the virtual channel based on individual time delays and accepts the virtual channel, if the total time delay does not exceed a predetermined maximum delay.

49. A method of claim 38, wherein an additional node present in or moving into the wireless network determines unreserved transmission resources and starts transmission of data during the unreserved transmission resources.

50. A method of claim 38, wherein an additional node present in or moving into the wireless network analyses virtual channel requests or data packets including reservation information of other nodes, or analyzes release messages, to determine unreserved transmission resources.

51. A method of claim 38, including monitoring the transmission path between the source node and the destination node to determine whether at least one of the intermediate nodes leaves the wireless network or if a connection is disturbed or broken.

52. A method of claim 38, wherein, if one of the at least one intermediate nodes leaves the wireless network or if a connection is disturbed or broken, the source node emits an additional virtual channel request to re-establish the virtual channel through an alternate path.

53. A method of claim 38, wherein, if one of the at least one intermediate nodes leaves the wireless network, an intermediate node preceding the leaving intermediate node determines an alternate path for the virtual channel to an intermediate node succeeding the leaving intermediate node.

54. A method of claim 38, including determining, if a connection between nodes is disturbed or broken, at an intermediate node preceding the disturbed or broken connection an alternate path for the virtual channel to an intermediate node succeeding the disturbed or broken connection.

55. A method of claim 38, wherein the source node, the at least one intermediate node and the destination node synchronize clocks using the periodic transmissions of a virtual channel.

56. A method of claim 38, wherein the wireless network is a multi hop wireless ad hoc network and/or forms part of a cellular network.

57. A program having instructions adapted to carry out the method of claim 38.

58. A computer readable medium, in which a program is embodied, wherein the program is to make a data processing device execute the method of claim 38.

59. A computer program product comprising the computer readable medium of claim 58.

60. A source node in a wireless network with distributed medium access control, including:

a request handler for transmitting a virtual channel request over a transmission path including at least one intermediate node to a destination node, the virtual channel request requesting an allocation of transmission resources for a virtual channel from the source node through the at least one intermediate node to the destination node and for receiving a virtual channel confirmation from the destination node, the virtual channel confirmation indicating an allocation of the resources for the virtual channel; and

a communication handler for transmitting data from the source node to the destination node using the allocated transmission resources.