Method and apparatus to avoid network congestion

A method to avoid network congestion, the method comprising:

• receiving a first control-message at a second node from a first node, wherein the first control-message contains a congestion-point identifier which is associated with a first queue at the first node;
• receiving a second message at the second node, wherein the second message is expected to be routed through the first queue at the first node;
• using information contained in the first control-message to determine whether to delay the second message;
• delaying the second message by queuing the second message in a second delay-queue at the second node;
• generating a second control-message at the second node, wherein the second control-message contains the congestion-point identifier;
• and
• sending the second control-message to a third node through a second link, wherein the second node is coupled to the third node using the second link;
• wherein sending the second control-message to the third node causes the third node to delay sending a third message to the second node, wherein the third message is expected to be routed through the first queue at the first node.

A computer-readable storage medium storing computer executable instructions that when executed by a computer cause the computer to perform a method to avoid network congestion, the method comprising:

• detecting an onset of congestion in a first queue at a first node, wherein the first node is coupled to a second node using a first link, wherein the onset of congestion is based at least on a threshold and a difference between an arrival rate of the first queue and an egress rate of the first queue;
• and wherein the threshold is based at least on a burst duration and the number of messages in the first queue;
• generating a first control-message at the first node, wherein the first control-message contains a congestion-point identifier which is associated with the first queue;
• and
• sending the first control-message to the second node through the first link, which causes the second node to delay sending a second message to the first node, wherein the second message is expected to be routed through the first queue at the first node, and wherein sending the first control-message to the second node causes the second node not to delay sending a third message to the first node, wherein the third message is not expected to be routed through the first queue at the first node.

A computer-readable storage medium storing computer executable instructions that when executed by a computer cause the computer to perform a method to avoid network congestion, the method comprising:

• receiving a first control-message at a second node from a first node, wherein the first control-message contains a congestion-point identifier which is associated with a first queue at the first node;
• receiving a second message at the second node, wherein the second message is expected to be routed through the first queue at the first node;
• using information contained in the first control-message to determine whether to delay the second message;
• delaying the second message by queuing the second message in a second delay-queue at the second node;
• generating a second control-message at the second node, wherein the second control-message contains the congestion-point identifier;
• and
• sending the second control-message to a third node through a second link, wherein the second node is coupled to the third node using the second link;
• wherein sending the second control-message to the third node causes the third node to delay sending a third message to the second node, wherein the third message is expected to be routed through the first queue at the first node.

An apparatus to avoid network congestion, the apparatus comprising:

• a detecting mechanism configured to detect an onset of congestion in a first queue at a first node, wherein the first node is coupled to a second node using a first link, wherein the onset of congestion is based at least on a threshold and a difference between an arrival rate of the first queue and an egress rate of the first queue;
• and wherein the threshold is based at least on a burst duration and the number of messages in the first queue;
• a first generating mechanism configured to generate a first control-message at the first node, wherein the first control-message contains a congestion-point identifier which is associated with the first queue;
• and
• a first sending mechanism configured to send the first control-message to the second node through the first link, wherein sending the first control-message to the second node causes the second node to delay sending a second message to the first node, wherein the second message is expected to be routed through the first queue at the first node, and wherein sending the first control-message to the second node causes the second node not to delay sending a third message to the first node, wherein the third message is not expected to be routed through the first queue at the first node.

An apparatus to avoid network congestion, the apparatus comprising:

• a first receiving mechanism configured to receive a first control-message at a second node from a first node, wherein the first control-message contains a congestion-point identifier which is associated with a first queue at the first node;
• a second receiving mechanism configured to receive a second message at the second node, wherein the second message is expected to be routed through the first queue at the first node;
• a determining mechanism configured to use information contained in the first control-message to determine whether to delay the second message;
• a delaying mechanism configured to delay the second message by queuing the second message in a second delay-queue at the second node;
• a generating mechanism configured to generate a second control-message at the second node, wherein the second control-message contains the congestion-point identifier;
• and
• a first sending mechanism configured to send the second control-message to a third node through a second link, wherein the second node is coupled to the third node using the second link;
• wherein sending the second control-message to the third node causes the third node to delay sending a third message to the second node, wherein the third message is expected to be routed through the first queue at the first node.