Detecting congestion by comparing successive loss of packets in windows to provide congestion control in reliable multicast protocol

• US 6,526,022 B1
• Filed: 06/18/1999
• Issued: 02/25/2003
• Est. Priority Date: 06/30/1998
• Status: Expired due to Term

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems (Oracle Corporation)
• Inventors: Perlman, Radia J., Chiu, Dah Ming, Hanna, Stephen R., Kadansky, Miriam C., Wesley, Joseph S., Hurst, Stephen A., Rosenzweig, Philip M.
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): PHAM, BRENDA H
• Application Number:
  US09/336,670
• Time in Patent Office: 1,348 Days
• Field of Search: 370/229, 370/230, 370/231, 370/232, 370/234, 370/235, 370/237, 370/242, 370/252, 370/253
• US Class Current: 370/229
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/1868 Measures taken after transmission, e.g. acknowledgments
• CPC Class Codes: H04L 2001/0092 Error control systems characterised by the topology of the transmission link
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/27 Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets

Abstract

A method of detecting congestion in a computer network uses a receiving station which determines a first number of messages missing in a first acknowledgment window. The station then determines a second number of messages missing in a subsequent acknowledgement window. The station then measures congestion on the network in response to an increase in the number of missing messages as indicated by the first number of missing messages in the first acknowledgement window and the second number of missing messages in the second acknowledgement window.

Claims

1. A method of detecting congestion in a computer network, comprising:

determining by a predetermined receiver station a first number of messages missing in a first acknowledgment window;

determining by said predetermined receiver station a second number of messages missing during a second acknowledgment window;

measuring congestion on the network in response to an increase in missing messages as indicated by said first number and said second number.

2. The method of claim 1 further comprising:

transmitting to a repair head station which is affiliated with said member station the count of missing messages in said first acknowledgement window and said second acknowledgement window.

3. The method of claim 1 further comprising:

transmitting to a repair head station which is affiliated with said member station the difference in count of missing messages in said first acknowledgement window and said second acknowledgement window.