Using PSTN reachability to verify VoIP call routing information

• US 8,675,642 B2
• Filed: 06/11/2012
• Issued: 03/18/2014
• Est. Priority Date: 07/20/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Rosenberg, Jonathan, Jennings, Cullen F., Wing, Daniel G.
• Primary Examiner(s): Phillips, Hassan
• Assistant Examiner(s): Mais, Mark A
• Application Number:
  US13/493,486
• Publication Number:
  US 20120243530A1
• Time in Patent Office: 645 Days
• Field of Search: None
• US Class Current: 370/353
• CPC Class Codes: H04L 65/1036 at the edge
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04M 2203/551 Call history recording a computer conference H04L12/1831
• CPC Class Codes: H04M 3/5125 with remote located operators
• CPC Class Codes: H04M 3/5232 Call distribution algorithms
• CPC Class Codes: H04M 7/0057 Services where the data services network provides a telephone service in addition or as an alternative, e.g. for backup purposes, to the telephone service provided by the telephone services network
• CPC Class Codes: H04M 7/006 Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04M 7/0063 where the network is a peer-to-peer network

Abstract

A system for verifying VoIP call routing information. In particular implementations, a method includes verifying one or more Voice-over-Internet-Protocol (VoIP) call agents for respective destination telephone numbers based on demonstrated knowledge of previous public switched telephone network (PSTN) calls to the respective destination telephone numbers; receiving a call initiation message identifying a destination telephone number; and conditionally initiating a call over a VoIP network to a target VoIP call agent, or over a circuit switched network, based on whether the target VoIP call agent has been verified for the destination telephone number identified in the call initiation message.

Claims

1. A method comprising:

initiating a public switched telephone network (PSTN) call to a destination telephone number;

storing an attribute of the PSTN call with a processor;

verifying with the processor that a Voice-over-Internet-Protocol (VoIP) call agent owns the destination telephone number by receiving an indication from the VoIP call agent that the VoIP call agent has knowledge of the attribute of the PSTN call initiated to the destination telephone number; and

providing Instant Messaging (IM) with the processor over a VoIP call to the VoIP call agent based on the verification that the VoIP agent owns the destination telephone number.

2. The method of claim 1 wherein the verifying comprises transmitting a query to the VoIP call agent for proof of knowledge of the attribute of the PSTN call, and wherein the receiving the indication comprises receiving a response to the query from the VoIP call agent that demonstrates knowledge of the attribute of the PTSN call.

3. The method of claim 1 further comprising discovering the VoIP call agent by querying a peer-to-peer network for a match with the destination telephone number.

4. The method of claim 3 wherein one or more members of the peer-to-peer network comprises VoIP call agents including the VoIP call agent.

5. The method of claim 1 further comprising discovering the VoIP call agent by querying a central server for a match with the destination telephone number.

6. The method of claim 1 wherein the attribute of the PSTN call comprises a dual-tone multi-frequency (DTMF) value transmitted over the PSTN call.

7. The method of claim 1 wherein the verifying that the VoIP call agent owns the destination telephone number is performed before the PSTN call ends.

8. A system comprising:

an originating Voice-over-Internet-Protocol (VoIP) call agent comprising a processor and a network interface, wherein the originating VoIP call agent is configured to;

initiate a public switched telephone network (PSTN) call to a destination telephone number with the processor over a PSTN;

store an attribute of the PSTN call;

verify that a destination Voice-over-Internet-Protocol (VoIP) call agent owns the destination telephone number based on receipt of an indication from the destination VoIP call agent over the network interface that the destination VoIP call agent has knowledge of the attribute of the PSTN call initiated to the destination telephone number; and

provide Instant Messaging (IM) between the originating VoIP call agent and the destination VoIP call agent over a VoIP call based on the verification that the destination VoIP agent owns the destination telephone number.

9. The system of claim 8, wherein the originating VoIP call agent is further configured to provide the IM over the VoIP call before the PSTN call ends.

10. The system of claim 8, wherein the originating VoIP call agent is further configured to provide the IM over the VoIP call when the destination VoIP agent is verified as owning the destination telephone and to provide the IM over the PSTN when the destination VoIP agent is not verified as owning the destination telephone number.

11. The system of claim 8, wherein the originating VoIP call agent is further configured to provide a video portion of an audio-visual communication session over the VoIP call and to provide a voice portion of the audio-visual communication session over the PSTN call in response to the verification that the destination VoIP call agent owns the destination telephone number.

12. The system of claim 8, wherein the attribute of the PSTN call comprises at least one of a start time of the PSTN call or an end time of the PSTN call.

13. The system of claim 8 further comprising a cache, wherein the originating VoIP call agent stores VoIP call routing information in the cache in response to the verification that the destination VoIP agent owns the destination telephone number, and provides the IM over the VoIP call in response to the VoIP call routing information being found in the cache.

14. The system of claim 8 wherein the receipt of the indication includes a use of an authentication protocol to verify that the destination VoIP call agent knows a password mapped from the attribute of the PSTN call without transmission of the attribute of the PSTN call between the destination VoIP call agent and the originating VoIP call agent.

15. Logic encoded in a tangible non-transitory computer readable storage medium executable with a processor to:

verify that a Voice-over-Internet-Protocol (VoIP) call agent owns a destination telephone number based on receipt of an indication from the VoIP call agent that the VoIP call agent has knowledge of an attribute of a public switched telephone network (PSTN) call initiated to the destination telephone number over a public switched telephone network;

store VoIP call routing information in a cache in response to the verification that the VoIP call agent owns the destination telephone number; and

provide Instant Messaging (IM) over a VoIP call to the VoIP call agent in response to the VoIP call routing information being found in the cache.

16. The computer readable storage medium of claim 15, wherein the logic encoded in the computer readable storage medium is further executable to:

search the cache for the VoIP call routing information based on the destination telephone number;

initiate the VoIP call if the VoIP call routing information is found in the cache; and

provide the Instant Messaging (IM) over the PSTN if the VoIP routing information is not found in the cache.

17. The computer readable storage medium of claim 15, wherein the PSTN call attribute comprises at least one of a caller identification, a call length, or a call signature.

18. The computer readable storage medium of claim 15, wherein the PSTN call attribute comprises a call signature, wherein the call signature is based on at least one of frequency spectrum analysis, silence detection, or a password.

19. The computer readable storage medium of claim 15, wherein the verification is performed after the PSTN call ends.

20. The computer readable storage medium of claim 15, wherein the logic encoded in the computer readable storage medium is further executable to identify the VoIP call agent from a search of a registry for the destination telephone number prior to the verification.