Method and system for diagnosing network congestion using mobile agents

• US 6,587,432 B1
• Filed: 08/31/1999
• Issued: 07/01/2003
• Est. Priority Date: 08/31/1999
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Yavatkar, Rajenda, Putzolu, David M.
• Primary Examiner(s): Yao; Kwang Bin
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US09/386,552
• Time in Patent Office: 1,400 Days
• Field of Search: 370/229-332,329,238,351,200,400,237 325/434,236.1,465,908,445,349,331-338,403-404 709/223-225,217-221,216,235-240 455/433,524 707/26,2-10 345/966,968 379/134
• US Class Current: 370/229
• CPC Class Codes: H04Q 2213/1305 Software aspects
• CPC Class Codes: H04Q 2213/13092 Scanning of subscriber lines, monitoring
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13106 Microprocessor, CPU
• CPC Class Codes: H04Q 2213/13145 Rerouting upon failure
• CPC Class Codes: H04Q 2213/13146 Rerouting upon blocking/overload, rearrangement
• CPC Class Codes: H04Q 2213/13162 Fault indication and localisation
• CPC Class Codes: H04Q 2213/13164 Traffic (registration, measurement,...)
• CPC Class Codes: H04Q 2213/13166 Fault prevention
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13299 Bus
• CPC Class Codes: H04Q 2213/13349 Network management
• CPC Class Codes: H04Q 2213/13389 LAN, internet
• CPC Class Codes: H04Q 3/0087 Network testing or monitoring arrangements

Abstract

A method and system analyze traffic on a network by monitoring network traffic and, when a particular network condition (for example, network congestion) is detected, gathering information about the traffic on the network by launching an agent and having the agent iteratively identify which of the links on the node on which the agent operates accepts a type or class of traffic, traverse the identified link to the node across the link, and repeat the process.

Claims

1. A method for analyzing a network, the network comprising nodes, each node connecting to a set of links, the method comprising:

at a first node on the network monitoring for a congestion condition; and

at the first node, if a congestion condition is detected, determining a set of traffic suspected to be congestion traffic and launching an agent, the agent recording information about traffic by;

detecting which among the links of the node at which the agent currently operates is receiving the most of the set of traffic suspected to be congestion traffic;

selecting a link found to be receiving the most of the subset of the set of traffic suspected to be congestion traffic and recording the identity of the selected link; and

attempting to move to the node connected to the selected link.

2. The method of claim 1 where the agent repeats detecting, selecting and attempting to move until the agent fails to perform one of detecting, selecting and attempting to move.

3. The method of claim 2 including, before launching the agent:

recording a set of samples of traffic receive at the first node; and

creating a list entries of sources producing traffic.

4. The method of claim 3 where the agent records the path of traffic produced by one entry in the list.

5. The method of claim 3 where the agent records the path of traffic produced by each entry in the list.

6. The method of claim 4 where the agent provides a report to a process executing on the first node.

7. The method of claim 2 where the information about the traffic includes at least a set of paths taken by the traffic.

8. The method of claim 2 where monitoring for a congestion condition is performed by a monitoring agent.

9. The method of claim 2 where the traffic suspected to be congestion traffic is traffic from a set of sender nodes.

10. The method of claim 9 where the agent detects which among the links of the node at which the agent currently operates is receiving the most of a subset of the set of traffic suspected to be congestion traffic by determining which of the links is receiving the most traffic from a selected node of the set of sender nodes.

11. The method of claim 10 where, when launched, the agent is given one node from the set of sender nodes, where the agent records information about traffic from the one node.

12. A system for analyzing traffic on a network, the network comprising nodes, each node having a set of links, the system comprising:

a first node having an agent for monitoring traffic, the agent for monitoring traffic having a monitoring code segment and a monitoring data segment; and

an agent for tracing traffic having a tracing code segment and a tracing data segment, the agent for tracing traffic gathering information about the traffic on the network by repeatedly;

identifying which of the links on the node on which the agent for tracing traffic operates accepts a class of traffic; and

traversing the identified link to the node across the link.

13. The system of claim 12 where the agent for monitoring traffic monitors for a congestion condition.

14. The system of claim 12 where the class of traffic is traffic from one of the nodes of the network.

15. The system of claim 12 where after the agent for tracing traffic identifies a link, the agent for tracing traffic records the node on which the agent for tracing traffic operates and the identified link.

16. The system of claim 12 where the agent for tracing traffic records a set of traffic paths, each traffic path specifying traffic flowing between the first node and one of the other nodes on the network.

17. A set of instructions residing in a storage medium, said set of instructions capable of being executed by a processor to implement a method for analyzing a network, the network comprising nodes, each node connecting to a set of links, the method comprising:

at a first node on the network monitoring for a congestion condition; and

at the first node, if a congestion condition is detected, determining a set of traffic suspected to be congestion traffic and launching an agent, the agent recording information about traffic by;

detecting which among the links of the node at which the agent currently operates is receiving the most of a subset of a set of traffic suspected to be congestion traffic;

selecting a link found to be receiving the most of the subset of the set of traffic suspected to be congestion traffic and recording the identify of the selected link;

attempting to move to the node connected to the selected link; and

repeating the detecting, selecting and attempting to move substeps until the agent fails to perform one of the detecting, selecting and attempting to move substeps.