Distributed call pickup group for VoIP system

• US 8,577,011 B1
• Filed: 01/09/2008
• Issued: 11/05/2013
• Est. Priority Date: 01/09/2008
• Status: Active Grant

• Current Assignee: ShoreTel Incorporated (Mitel Networks Corporation)
• Original Assignee: ShoreTel Incorporated (Mitel Networks Corporation)
• Inventors: Madabhushi, Pramod
• Primary Examiner(s): SHAH, ANTIM G
• Application Number:
  US11/971,837
• Time in Patent Office: 2,127 Days
• Field of Search: 379/207.02, 379/207.12, 379/211.02, 379/212.01, 379/214.01, 379/220.01, 379/265.01, 379/265.11, 379/266.01, 379/266.04, 379/271, 379/272, 379/273, 379/274, 379/352
• US Class Current: 379/212.01
• CPC Class Codes: H04M 3/42212 Call pickup comprising simultaneous alerting H04M3/46
• CPC Class Codes: H04M 3/42323 PBX's with CTI arrangements

Abstract

A distributed call pickup group system comprises a call manager having an extension module. The extension module further comprises a group pickup module, a group pickup call stack, a backup group pickup module and a monitoring group pickup module. The extension module controls and manages the functionality associated with the group pickup feature. The group pick module advantageously allows any extension regardless of its location in the system or the switch to which it is connected to be included within a pickup group. The backup group pickup module provides fault tolerance for the pickup functionality such that if a particular switch and its associated group pickup module fail, a backup group pickup module is identified and made operational. The present invention also includes a variety of methods including a method for creating a group pickup list, a method for performing through pickup and a method for backing up group picked up.

Claims

1. A system for providing group pickup in a telephony system, the system comprising:

an extension list including a group pickup list;

a monitoring group pickup module for receiving an incoming call, determining a destination extension and determining other extensions in the same group pickup list as the destination extension, the monitoring group pickup module generating an indication signal that provides information necessary to redirect the incoming call, the monitoring group pickup module coupled to access the extension list;

a group pickup call stack for storing information about incoming calls until they are redirected; and

a group pickup module for receiving the indication signal and a pickup signal and processing the incoming call to redirect the incoming call to an extension that sent the pickup signal using the indication signal generated by the monitoring group pickup module, managing the group pickup call stack, receiving a keep alive signal corresponding to a pending call stored in the group pickup call stack, and removing the pending call from the group pickup call stack if the keep alive signal is not received for the pending call within a predetermined amount of time, the group pickup module coupled to the monitoring group pickup module to receive the indication signal, and the group pickup module coupled to the extension to receive the pickup signal and redirect the incoming call and adapted for communication with the group pickup call stack.

2. The system of claim 1 wherein the group pickup module is part of a call manager.

3. The system of claim 1 wherein the group pickup module is part of an extension module of a call manager.

4. The system of claim 1 further comprising a second group pickup module for processing calls associated with a second group pickup list, and wherein the extension list includes the second group pickup list.

5. The system of claim 4 wherein the group pickup module is operational as part of a first switch and the second group pickup module is operational as part of a second switch.

6. The system of claim 1 further comprising a backup group pickup module for providing a failover mechanism, the backup group pickup module coupled to receive a signal indicating a primary group list is not available from the monitoring group pickup module and forwarding the incoming call to a secondary group list when the primary group list is not available, the backup group pickup module adapted for communication with the group pickup module and the monitoring group pickup module.

7. The system of claim 1 wherein:

the group pickup module, the monitoring group pickup module and the extension list are operational as part of a first switch;

the extension list includes a first endpoint coupled to the first switch and a second endpoint coupled to a second switch; and

the group pickup module is coupled to receive the pickup signal from one of the first endpoint and the second endpoint and redirect the incoming call to the one of the first endpoint and the second endpoint.

8. The system of claim 1 wherein:

the extension list includes the group pickup list and a second group pickup list; and

the system further comprises an endpoint having an extension number and the extension number is included in both the group pickup list and the second group pickup list.

9. A method for performing call group pickup by a call manager having a group pickup module, the method comprising:

receiving an incoming call;

determining with the call manager a first extension for the incoming call;

determining by the call manager whether the first extension is included in a group pickup list;

receiving by the group pickup module a pickup signal from a second extension;

storing information about the incoming call until it is redirected in a group pickup call stack;

redirecting using the group pickup module the incoming call to the second extension using an indication signal that provides information necessary to redirect the incoming call;

receiving a keep alive signal corresponding to a pending call stored in the group pickup call stack; and

removing the pending call from the group pickup call stack if the keep alive signal is not received for the pending call within a predetermined amount of time.

10. The method of claim 9, wherein the call manager and the group pickup module are operational on a first switch and the second extension is operational on a second switch.

11. The method of claim 9, further comprising:

determining a switch for the group pickup list and determining whether the switch is operational;

if the switch is operational, sending a message to a group extension; and

if the switch is not operational, determining a backup group extension and sending the message to the backup group extension.

12. The method of claim 9, further comprising:

determining whether the incoming call is present; and

sending the keep alive signal if the incoming call is present.

13. The method of claim 9, further comprising sending a message to the group pickup list.

14. The method of claim 13 further comprising storing the indication signal in a call stack, and wherein redirecting the incoming call also includes removing the indication signal from the call stack.

15. The method of claim 9, further comprising monitoring for the pickup signal and determining whether the incoming call is still present.

16. A non-transitory computer-readable storage medium storing instructions that when executed by a computer cause the computer to perform a method of performing call group pickup, the method comprising:

receiving an incoming call;

determining with a call manager a first extension for the incoming call;

determining by the call manager whether the first extension is included in a group pickup list;

receiving by a group pickup module a pickup signal from a second extension;

storing information about the incoming call until it is redirected in a group pickup call stack;

redirecting using the group pickup module the incoming call to the second extension using an indication signal that provides information necessary to redirect the incoming call;

receiving a keep alive signal corresponding to a pending call stored in the group pickup call stack; and

removing the pending call from the group pickup call stack if the keep alive signal is not received for the pending call within a predetermined amount of time.

17. The non-transitory computer-readable storage medium of claim 16, wherein the call manager and the group pickup module are operational on a first switch and the second extension is operational on a second switch.

18. The non-transitory computer-readable storage medium of claim 16, further comprising:

determining a switch for the group pickup list and determining whether the switch is operational;

if the switch is operational, sending a message to a group extension; and

if the switch is not operational, determining a backup group extension and sending the message to the backup group extension.