Method of dynamically routing to a well known address in a network

• US 6,205,146 B1
• Filed: 05/28/1998
• Issued: 03/20/2001
• Est. Priority Date: 05/28/1998
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Morgenstern, Meir, Rochberger, Haim, Margulis, David, Shani, Sarit
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US09/086,423
• Time in Patent Office: 1,027 Days
• Field of Search: 370/387, 370/395, 370/238, 370/255, 370/254, 370/256, 370/408, 370/466, 370/399, 370/389, 370/352, 370/410, 370/252, 370/329, 370/336, 709/239, 709/203, 709/218, 709/249, 709/225, 709/217, 709/224, 709/238
• US Class Current: 370/395.53
• CPC Class Codes: H04L 45/10 Routing in connection-oriented networks, e.g. X.25 or ATM
• CPC Class Codes: H04L 45/122 by minimising distances, e.g. by selecting a route with minimum of number of hops

Abstract

A method of determining an efficient route to a well known address that is particularly applicable to networks that do not have the capability of source routing for calculating routes to specific addresses such as ATM networks based on the IISP protocol. The well known address may represent any entity in the network that provides distributed services (e.g., network server applications) that are to be shared among many nodes and applications on the network, such as LECSs. The method of functions to automatically and dynamically register ‘well known’ addresses on the ports of each node that implements the invention. This permits applications on the network to route to the destination in the shortest possible path thus utilizing network resources in an efficient manner. If there is more than one location with the well known address, e.g., a redundant LECSs in the network, or more than one route to the location then the optimum location will be the one routed to. An optimum location can be determined using any suitable criteria to determine the optimum route to a LECS such as distance, hop count, cost function, link sum, link capacity, etc.

Claims

1. In an Asynchronous Transfer Mode (ATM) network having a plurality of nodes, a network server application implemented on one of said nodes, a method of routing to a well known address, said method comprising the steps of:

sending an indication message containing a cost value on a periodic basis out on all Network to Network Interface (NNI) ports in the node that implements said network server application;

receiving a message containing said cost value on a node;

registering said well known address and a received cost value associated therewith on the port receiving said indication message if said well known address has not been previously registered;

updating an existing cost value with said received cost value;

incrementing said received cost value by one to yield a new cost value;

forwarding an indication message containing said new cost value out on ports having a larger cost value registered therewith and on ports without a registered cost value if said received cost value is smaller than or equal to the smallest cost value associated with other NNI ports; and

routing a call request to said network server application, made by a user connected to a node, via the port with the smallest cost value associated therewith.

2. The method according to claim 1, wherein said network server application comprises a LAN Emulation Configuration Server (LECS).

3. The method according to claim 1, wherein said cost value and said new cost value comprise a hop count and new hop count, respectively.

4. The method according to claim 1, wherein said cost value and said new cost value comprise a cost function and new cost function, respectively.

5. The method according to claim 1, wherein said cost value and said new cost value comprise a link sum and new link sum, respectively.

6. The method according to claim 1, wherein said step of sending an indication message comprises the step of sending an Interim Local Management Interface (ILMI) trap message containing said cost value.

7. The method according to claim 1, further comprising the steps of:

resetting a timer associated with each port within each node when an indication message is received thereon; and

deleting said well known address associated with a particular port if said timer expires.

8. The method according to claim 1, wherein said network comprises a plurality of network server applications, said network server applications implemented on one or more nodes.

9. The method according to claim 1, further comprising the step of performing load sharing when routing said call request to said network server application in the event more than one port has a smallest cost value associated therewith.

10. In an Asynchronous Transfer Mode (ATM) network having a plurality of nodes, a LAN Emulation Configuration Server (LECS) implemented one of said nodes, a method of routing to a well known address, said method comprising the steps of:

sending an indication message containing a hop count on a periodic basis out on all Network to Network Interface (NNI) ports in the node that implements said LECS;

receiving a message containing said hop count on a node;

registering said well known address and a received hop count associated therewith on the port receiving said indication message if said well known address has not been previously registered;

updating an existing hop count with said received hop count;

incrementing said received hop count by one to yield a new hop count;

forwarding an indication message containing said new hop count out on ports having a larger hop count registered therewith and on ports without a registered hop count if said received cost value is smaller than or equal to the smallest hop count associated with other NNI ports; and

routing a call request to said LECS, made by a user connected to a node, via the port with the smallest hop count associated therewith.

11. The method according to claim 10, wherein said step of sending an indication message comprises the step of sending an Interim Local Management Interface (ILMI) trap message containing said cost value.

12. The method according to claim 10, further comprising the steps of:

resetting a timer associated with each port within each node when an indication message is received thereon; and

deleting said well known address associated with a particular port if said timer expires.

13. The method according to claim 10, further comprising the step of performing load sharing when routing said call request to said network server application in the event more than one port has a smallest hop count associated therewith.