Method for performing a load distribution between session initiation protocol servers within an intra domain

• US 20030110257A1
• Filed: 12/10/2002
• Published: 06/12/2003
• Est. Priority Date: 12/11/2001
• Status: Abandoned Application

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Kang, Shin Gak, Hyun, Wook, Huh, Mi Young
• Application Number:
  US10/314,940
• Publication Number:
  US 20030110257A1
• Time in Patent Office: Days
• US Class Current: 709/224
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1036 Load balancing of requests to servers for services different from user content provisioning, e.g. load balancing across domain name servers

Abstract

A load distribution is performed between session initiation protocol (SIP) servers in an intra domain.

By employing a distribution process and a function-based server characterization, loads of a single representative proxy can be effectively distributed and a call processing capacity can be maximized while maintaining compatibility with existing proxies.

Claims

1. A method for performing a load distribution between SIP servers in an intra domain having a SIP load distributor (SLD) server for processing a SIP request by conducting a DB search function and a load distribution function, the method comprising the steps of:

(a) transmitting the SIP request from a representative proxy of the intra domain to the SLD server;

(b) retrieving a user address for the SIP request and adding the retrieved user address to the SIP request;

(c) searching for a least loaded proxy in a load management table and applies a load increment required to process the SIP request to a load record for the least loaded proxy in the load management table; and

(d) sending the SIP request to the least loaded proxy.

2. The method of claim 1, wherein the step (b) includes the step of transmitting a ‘

not found’

response to the representative proxy if there exists no user address.

3. The method of claim 1, wherein the step (c) includes the step of adding a Proxy-Require header specifying a “

PreLoadedContact”

header, writing a user address in the “

PreLoadedContact header” and

adding a via adder designating the SLD server.

4. A method for performing a load distribution between SIP servers in an intra domain having a SLD server for processing a SIP response by conducting a DB search function and a load distribution function, the method comprising the steps of:

(a) analyzing a response code of the SIP response transmitted from an internal proxy to the SLD server;

(c) applying to a load management table a load decrement of the internal proxy according to a transmission of a final response if the response code is found to be the final response and transmitting the SIP response to the representative proxy;

(c) generating a new SIP request if the response code is determined as a response for notifying incompatibility with the internal proxy, sending the newly generated SIP request to the internal proxy and applying a load increment of the internal proxy to the load management table of the SLD server; and

(d) transmitting the SIP response to the representative proxy if the response code is found to be an informational response.

5. The method of claim 4, wherein the step (b) includes the step of searching a call management table if the SIP response is received at the SLD server from the representative proxy and deleting from the SIP response a via header and a record route header if there exist a search result.

6. The method of claim 4, wherein the response for notifying the incompatibility with the internal proxy is a “

Bad Extension”

response.