METHOD AND SYSTEM FOR ENFORCING PROXY USE WITHIN AN ENTERPRISE COMMUNICATIONS SYSTEM

• US 20090003325A1
• Filed: 02/29/2008
• Published: 01/01/2009
• Est. Priority Date: 06/29/2007
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Research In Motion Limited (Blackberry Limited)
• Inventors: LEE, DALSU, Shatsky, Alexander
• Granted Patent: US 9,270,707 B2
• Time in Patent Office: Days
• US Class Current: 370/353
• CPC Class Codes: H04L 65/1045 Proxies, e.g. for session initiation protocol [SIP]
• CPC Class Codes: H04L 65/1053 IP private branch exchange [PBX] functionality entities or arrangements circuit switched PBXs H04M3/00
• CPC Class Codes: H04L 65/1073 Registration or de-registration
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]

Abstract

A method and system for enforcing the user of a proxy server within an enterprise communication system. The system includes an enterprise voice application server configured to act as a SIP proxy to client devices, and a private branch exchange configured to act as a SIP registrar. The client devices are configured to evaluate incoming SIP requests to determine whether they were received via the enterprise voice application server and, if not, to respond with a SIP 305 Use Proxy message referencing the enterprise voice application server in a Contact field. The 305 Use Proxy message forces the PBX or other intermediate SIP server to reroute the SIP request and any subsequent SIP requests in the dialog through the enterprise voice application server.

Claims

1. A method of enforcing use of an enterprise voice application server as a SIP proxy server for enterprise VoIP communications, wherein the enterprise includes a client device having a first IP address and a client uniform resource identifier (URI), and a Private Branch exchange (PBX) configured as a SIP registrar having a registration entry binding the client URI to the first IP address, the enterprise voice application server having a proxy URI and a second IP address, the method comprising the steps of:

receiving, at the client device, a SIP request message from the PBX addressed to the client URI; and

determining whether the SIP request message was sent via the enterprise voice application server and, if not, then

generating and sending a SIP 305 Use Proxy response message to the PBX, wherein the SIP 305 Use Proxy response message references the enterprise voice application server in a Contact field, and

re-receiving the SIP request message from the PBX routed via the enterprise voice application server.

2. The method claimed in claim 1, wherein the SIP request message is an INVITE message relating to a call request from a remote party received by the PBX over the public switched telephone network.

3. The method claimed in claim 1, further including steps of sending a SIP REGISTER request to the enterprise voice application server and receiving a SIP 200 OK response message.

4. The method claimed in claim 3, further including steps of forwarding the SIP REGISTER request from the enterprise voice application server to the PBX, and creating the registration entry.

5. The method claimed in claim 1, wherein the PBX is configured to refuse a registration request that results in binding more than one URI to the same Contact address.

6. The method claimed in claim 1, wherein the step of determining comprises reading a Via header of the SIP request message and determining that an address for the enterprise voice application server is not listed in the Via header.

7. The method claimed in claim 1, wherein the client device comprises one of a mobile device, softphone, and desk telephone set.

8. The method claimed in claim 1, wherein the SIP 305 Use Proxy response message includes the Proxy URI in the Contact field.

9. The method claimed in claim 1, wherein the SIP 305 Use Proxy response message includes the second IP address in the contact field.

10. A client device associated with an enterprise, the enterprise including a Private Branch exchange (PBX) configured as a SIP registrar and an enterprise voice application server having a proxy uniform resource identifier (URI) and a second IP address, the mobile device comprising:

a communications subsystem for engaging in IP-based communications with the enterprise, wherein the client device is configured to be assigned a first IP address and a client URI;

a memory;

a user interface for outputting information and for receiving user input;

a processor for controlling the communications subsystem, the memory, and the user interface; and

a communication application executable by the processor and configured to receive a SIP request message from the PBX addressed to the client URI,

wherein the SIP registrar includes a registration entry binding the client URI to the first IP address,

and wherein the communication application is configured to determine whether the SIP request message was sent via the enterprise voice application server,

and wherein the communication application is configured to generate and send a SIP 305 Use Proxy response message to the PBX if the SIP request message was not sent via the enterprise voice application server, wherein the SIP 305 Use Proxy response message references the enterprise voice application server in a Contact field.

11. The client device claimed in claim 10, wherein the SIP request message is an INVITE message relating to a call request from a remote party received by the PBX over the public switched telephone network.

12. The client device claimed in claim 10, wherein the communication application is configured to read a Via header of the SIP request message and evaluate whether an address for the enterprise voice application server is listed in the Via header to determine whether the SIP request message was sent via the enterprise voice application server.

13. The client device claimed in claim 10, wherein the client device comprises one of a mobile device, softphone, and desk telephone set.

14. The client device claimed in claim 10, wherein the SIP 305 Use Proxy response message includes the Proxy URI in the Contact field.

15. The client device claimed in claim 10, wherein the SIP 305 Use Proxy response message includes the second IP address in the contact field.

16. A computer program product comprising a machine-readable medium having encoded thereon computer executable instructions for enforcing use of an enterprise voice application server as a SIP proxy server for enterprise VoIP communications, wherein the enterprise includes a client device having a first IP address and a client uniform resource identifier (URI), and a Private Branch exchange (PBX) configured as a SIP registrar having a registration entry binding the client URI to the first IP address, the enterprise voice application server having a proxy URI and a second IP address, the computer-executable instructions comprising:

instructions for receiving, at the client device, a SIP request message from the PBX addressed to the client URI;

istructions for determining whether the SIP request message was sent via the enterprise voice application server; and

instructions for generating and sending a SIP 305 Use Proxy response message to the PBX if the SIP request message was not sent via the enterprise voice application server, wherein the SIP 305 Use Proxy response message references the enterprise voice application server in a Contact field.