Method and apparatus for contention management in a radio-based packet network

• US 20030002442A1
• Filed: 06/27/2001
• Published: 01/02/2003
• Est. Priority Date: 06/27/2001
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Metricom, Inc.
• Inventors: Paulsen, David L., Flammer, George H. III, Ritter, Michael W.
• Granted Patent: US 6,999,441 B2
• Time in Patent Office: Days
• US Class Current: 370/230
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 74/06 using polling

Abstract

In a mesh communication network, a poll request protocol (PRP) is provided in which a special packet is broadcast by the congested node when it is ready to provide services. The controlling node (usually the more congested node) broadcasts a packet to request poll signals from nodes desiring resources of the controlling node. The contending nodes then have equal chances to request the services of the controlling node by sending poll signals. The controlling node can then arbitrate the requests, determine the most fair and efficient use of its resources, and broadcast a scheduling packet to inform the contending nodes when to inform the contending nodes of controlling node scheduling. The contending nodes then send their packets to the controlling node without lost packets caused by congestion collisions. The controlling node can then send data to the contending nodes also without lost packets.

Claims

1. A method for requesting access to a congested communication node in a mesh communication packet network comprising:

withholding, at a requesting node, requests for access to said congested communication node while awaiting receipt, at said requesting node, of a poll request packet containing a first datum of information indicating availability of a communication slot;

broadcasting from said congested communication node said poll request packet when said congested communication node is ready to provide services; and

thereafter

directing from said requesting node a poll packet to request access to the congested node.

2. The method according to claim 1, wherein the controlling node is a more congested node, the method further comprising

broadcasting from the controlling node a packet which is operative to request poll signals from those nodes desiring resources of the controlling node;

sending from the controlling nodes requests of optimally transmitting data between the controlling node and the requesting nodes;

broadcasting a control packet with information from the congested node that directs the requesting nodes when to send and receive data; and

thereafter

causing each individual requesting node to transmit local data in turn to the controlling node.

3. The method of claim 2 farther including thereafter:

scheduling each individual requesting node which receives data from the controlling node, if such data is available, as scheduled by the controlling node;

thereafter

receiving at each individual requesting node acknowledgments of corresponding individually transmitted data packets from the controlling node; and

thereafter

transmitting from each individual requesting node further acknowledgments to receipt of data if data has been previously transmitted to it by the controlling node.

4. The method according to claim 3 further comprising:

purging data packets from a transmitting node upon receipt of acknowledgment of successful reception of said data packets.

5. An apparatus for requesting access to a congested communication node in a mesh communication packet network comprising:

means for withholding, at a requesting node, requests for access to said congested communication node while awaiting receipt, at said requesting node, of a poll request packet containing a first datum of information indicating availability of a communication slot;

broadcasting means for broadcasting from said congested communication node said poll request packet when said congested node is ready to provide services; and

thereafter

means at said requesting node for directing from said requesting node a poll packet to request access to the congested node.

6. The apparatus according to claim 5, wherein the controlling node is a more congested node and wherein the controlling node is operative to broadcast a packet requesting poll signals from the nodes desiring resources of the controlling node and the controlling node is operative to have sent the requests of optimally transmitting data between the controlling node and the requesting nodes, further comprising:

means operative to broadcast a control packet from the congested node that directs the requesting nodes when to send and receive data packets; and

means to cause thereafter each individual requesting node to transmit its data packets in turn to the controlling node.

7. The apparatus according to claim 6 further including:

means at said controlling node for scheduling transmitting times for each individual requesting node which receives data from the controlling node, if such data is available;

means for receiving at each individual requesting node acknowledgments of corresponding individually transmitted data packets from the controlling node; and

means for transmitting from each individual requesting node further acknowledgments to receipt of data if data has been previously transmitted to it by the controlling node.

8. The apparatus according to claim 7 further comprising:

means for purging data packets from a transmitting node upon receipt of acknowledgment of successful reception of said data packets.