CORRELATING CALLS AFTER A REFERRAL

• US 20120224676A1
• Filed: 05/21/2012
• Published: 09/06/2012
• Est. Priority Date: 02/09/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Wu, Shuojiun, CAI, Yuan
• Granted Patent: US 8,787,213 B2
• Time in Patent Office: Days
• US Class Current: 379/88.19
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways

Abstract

In one embodiment, a network device attaches a header including an identifier for an original call to an outgoing refer message and may also modify a table entry for a consultative call to include the identifier. The network device then monitors incoming invite messages for a header containing the identifier and observes that an incoming invite message containing the header correlates to the original call. When a header is not included, the network device extracts information from the incoming invite messages and compares the extracted information to the modified table entry to correlate one of the incoming invite messages to the original call.

Claims

1. An apparatus, comprising:

a processing device; and

a memory coupled to the processing device comprising instructions executable by the processing device, the processing device operable when executing the instructions to;

pass user data between a first endpoint and a second endpoint that is different than the first endpoint during a first voice call;

receive, during the first voice call, a refer message from one of the first and second endpoints, the incoming refer message configured to cause the other one of the first and second endpoints to send an invite to a third endpoint that is different than the first endpoint and different than the second endpoint for establishing a second voice call between the third endpoint and only the other one of the first and second endpoints;

attach a call identifier having a value for the first voice call to the refer message and pass the refer message having the attached identifier to a remote device;

monitor incoming invites for the value to distinguish the invite originating from the other one of the first and second endpoints and resulting from the refer message from other received invites; and

in response to observing the value in the invite from the other one of the first and second endpoints, store in a database a correlation between the second voice call between the third endpoint and only the other one of the first and second endpoints to the first voice call between the first and second endpoints.

2. The apparatus of claim 1, wherein the call identifier is a Global Call IDentifier (GCID).

3. The apparatus of claim 1, wherein the refer message comprises a Session Initiation Protocol (SIP) refer message.

4. The apparatus of claim 1, wherein the invite comprises a SIP invite.

5. A method, comprising:

passing user data between a first endpoint that is different than the first endpoint and a second endpoint during a first voice call;

receiving, during the first voice call, a refer message from one of the first and second endpoints, the incoming refer message configured to cause the other one of the first and second endpoints to send an invite to a third endpoint that is different than the first endpoint and different than the second endpoint for establishing a second voice call between the third endpoint and only the other one of the first and second endpoints;

generating an entry in an active call table for the first voice call, the generated entry including a value for the first voice call;

comparing information from fields of incoming invites to the active call table to correlate a particular one of the incoming invites to the generated entry; and

based on the correlation, storing in a database an association between the second voice call between the third endpoint and only the other one of the first and second endpoints to the first voice call between the first and second endpoints.

6. The method of claim 5, wherein the value is a Global Call IDentifier (GCID) stored in a private data space of the entry in the active call table.

7. The method of claim 6, wherein the active call table includes other entries for other types of active calls.

8. The method of claim 5, wherein the refer message comprises a Session Initiation Protocol (SIP) refer.

9. The method of claim 5, wherein the particular incoming invite comprises a SIP invite.

10. The method of claim 5, wherein the fields comprise consult dialog information fields.

11. An apparatus, comprising:

a processing device; and

a memory coupled to the processing device comprising instructions executable by the processing device, the processing device operable when executing the instructions to;

pass user data between a first endpoint and a second endpoint that is different than the first endpoint during a first voice call;

receive, during the first voice call, a refer message from one of the first and second endpoints, the incoming refer message configured to cause the other one of the first and second endpoints to send an invite to a third endpoint that is different than the first endpoint and different than the second endpoint for establishing a second voice call between the third endpoint and only the other one of the first and second endpoints;

observe a value associated with the first voice call in response to receiving the refer message and pass the refer message to a remote device;

analyze information contained in incoming invites, the analysis utilizing the value observed in response to receiving the refer message in order to correlate a particular one of the incoming invites to the first voice call; and

based on the correlation, store in a database an association between the second voice call between the third endpoint and only the other one of the first and second endpoints to the first voice call between the first and second endpoints.

12. The apparatus of claim 11, wherein the processing device is further operable to:

attach a call identifier having the value to the refer message and pass the refer message having the attached identifier to a remote device;

monitor the incoming invites for the value to distinguish the invite originating from the other one of the first and second endpoints and resulting from the refer message from the other received invites; and

in response to observing the value in the invite from the other one of the first and second endpoints, store in the database the association between the second voice call between the third endpoint and only the other one of the first and second endpoints to the first voice call between the first and second endpoints.

13. The apparatus of claim 11, wherein the processing device is further operable to:

generate an entry in an active call table for the first voice call, the generated entry including the value;

compare information from consult dialog information fields of the incoming invites to the active call table to distinguish the invite originating from the other one of the first and second endpoints and resulting from the refer message from the other received SIP invites; and

store in the database the association between the second voice call between the third endpoint and only the other one of the first and second endpoints to the first voice call between the first and second endpoints.

14. The apparatus of claim 11, wherein the refer message comprises a Session Initiation Protocol (SIP) refer message.

15. The apparatus of claim 11, wherein the invite comprises a SIP invite.