Method and apparatus for determining accurate topology features of a network

• US 6,405,248 B1
• Filed: 07/06/2000
• Issued: 06/11/2002
• Est. Priority Date: 12/02/1998
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: Micromuse Incorporated (International Business Machines Corporation)
• Inventors: Wood, Michael
• Primary Examiner(s): Geckil, Mehmet B.
• Application Number:
  US09/611,408
• Time in Patent Office: 705 Days
• Field of Search: 709/223, 709/224, 709/220, 709/221, 709/227, 709/229, 709/238, 709/245, 709/249, 709/203, 370/253, 370/409, 370/397, 370/401, 370/351
• US Class Current: 709/223
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies

Abstract

A monitoring system for determining accurate topology features of a network, and methods of operating the monitoring system, are disclosed. In the preferred embodiment, the system creates an accurate topology map of a given network by: obtaining a list of managed network devices; identifying trunk ports, link channel ports, and trunk channel ports; identifying link port and node ports; determining connections between the ports; storing the collected information; and displaying the network topology. Methods are disclosed for identifying link and node ports. In the preferred method, information regarding the devices; including VLAN/backplane information, router ARP table information, device interface information, and physical address information for machines and devices connected to the network is obtained. Also, the ports and/or devices are logically grouped in order to provide more accurate topology information. Source address table timing information is obtained for each device, and a historical database of source table information is kept. Filters may then be utilized on the source address tables in order to provide more accurate topology results. Connections between nodes are also resolved by utilizing sorting methods. Alternative methods are also disclosed for identifying link ports and determining connections between nodes.

Claims

1. A method for determining topology features of a computer network comprising:

identifying devices on the network;

identifying channel and trunk ports on the network;

identifying link and node ports on the network; and

determining connections between the devices and ports on the network.

2. The method of claim 1, wherein the step of determining connections between the devices and ports on the network includes the step of determining link and channel link connections.

3. The method of claim 1, wherein the step of determining connections between the devices and ports on the network further includes the step of determining trunk and channel trunk connections.

4. The method of claim 1, wherein the step of identifying link and node ports on the network includes the step of assigning logical port numbers to the ports.

5. The method of claim 1, wherein the step of identifying link and node ports on the network includes the steps of:

assigning local domains;

assigning global domains;

assigning link domains; and

determining which link domains can communicate with each other without the assistance of a router.

6. The method of claim 1, wherein the step of identifying link and node ports on the network includes the steps of:

assigning local domains;

assigning global domains; and

determining which of the local domains and global domains can communicate with each other without the assistance of a router.

7. The method of claim 6, wherein the step of assigning global domains includes the step of determining which of the local domains are extended among two or more devices via trunk ports and/or trunk channels.

8. The method of claim 6, wherein the step of determining which of the local domains and global domains can communicate with each other without the assistance of a router includes the step of determining every router that uses unique source addresses on its interfaces.

9. The method of claim 6, wherein the step of determining which of the local domains and global domains can communicate with each other without the assistance of a router includes the step of utilizing source addresses relating to network interface cards.

10. The method of claim 6, wherein the step of determining which of the local domains and global domains can communicate with each other without the assistance of a router includes the step of utilizing router ARP tables.

11. The method of claim 6, wherein the step of determining which of the local domains and global domains can communicate with each other without the assistance of a router includes the step of filtering source address tables from ARP tables that are present on multiple router interfaces.

12. The method of claim 6, wherein the step of determining which of the local domains and global domains can communicate with each other without the assistance of a router includes the step of utilizing cam tables from switches and bridges in the network.

13. The method of claim 6, wherein the step of determining which of the local domains and global domains can communicate with each other without the assistance of a router includes the step of identifying circuits to identify every device that has only one interface.

14. The method of claim 6, wherein the step of determining which of the local domains and global domains can;

communicate with each other without the assistance of a router includes the step of utilizing set theory for devices that have multiple interfaces.

15. The method of claim 6, wherein the step of assigning local domains includes the step of identifying a group of ports on a single device such that any node connected to one port in the group can communicate to any other port in the group.

16. The method of claim 6, wherein the step of determining connections comprises the steps of:

(a) selecting a circuit from a list of assigned circuits;

(b) selecting a link domain in the circuit;

(c) selecting a source address on the link domain from a link port;

(d) selecting a source address on the chosen link domain from a node port;

(e) identifying all link domains containing the source address from step (c) and the source address from (d) on different ports;

(f) sorting all link domains until all are sorted;

(g) assigning connections to each link domain according to sort order;

(h) repeating steps (c)-(g) for each link port on the link domain;

(i) repeating steps (b)-(h) for each link domain in the circuit;

(j) repeating steps (a)-(i) for each circuit.