Telephony communication via varied redundant networks

• US 8,379,531 B2
• Filed: 09/29/2008
• Issued: 02/19/2013
• Est. Priority Date: 04/18/1996
• Status: Expired due to Fees

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Services Corporation (Verizon Communications Inc.)
• Inventors: Farris, Robert D., Bartholomew, Dale L.
• Primary Examiner(s): Pezzlo, John
• Application Number:
  US12/240,565
• Publication Number:
  US 20090022147A1
• Time in Patent Office: 1,604 Days
• Field of Search: 370/252, 370/352, 370/400
• US Class Current: 370/252
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 65/1083 In-session procedures
• CPC Class Codes: H04L 65/1095 Inter-network session transfer or sharing
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04M 2207/12 intelligent networks
• CPC Class Codes: H04M 3/367 Traffic or load control
• 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 7/066 where the auxiliary connection is via an Internet Protocol network interworking of signalling system number 7 (SS7) with Internet Protocol-based session control protocols H04M7/1265, H04M7/127
• CPC Class Codes: H04M 7/1245 where a network other than PSTN/ISDN interconnects two PSTN/ISDN networks
• CPC Class Codes: H04Q 3/0025 Provisions for signalling
• CPC Class Codes: H04Q 3/0029 Provisions for intelligent networking

Abstract

A switched telephone network is arranged in a manner to enable packet voice communication between telephone terminals via multiple redundant packet switched networks. The packet switched networks may utilize different protocols, be operated by different entities, and have primary functions other than voice communication. One example of such a network may be internetworked networks, such as the Internet. One example of an alternate packet switched network may be a network whose primary function is control of a circuit switched telephone network. The common channel interoffice switching system (CCIS) of a public switched telephone network (PSTN) is a preferred example.

A voice communication link may be established from telephone terminal to telephone terminal via the Internet, the quality of voice communication may be monitored, and the link may be transferred to the common channel interoffice signaling network if and when the quality of voice communication deteriorates beneath a pre-established norm. There is provided a means for monitoring the links of the common channel interoffice signaling system carrying the packetized voice communication and collecting the information needed to permit charging for the voice communication by time duration or by cells used to carry the packetized voice signal. The customer may be provided with the option of establishing the norm for diversion of the communication, or may elect which path is to be selected as the primary path.

Claims

1. A method, comprising:

establishing a first communication link between a first terminal and a second terminal via a packet switched network;

transmitting voice information between the first terminal and the second terminal over the first communication link;

monitoring a quality of service of the first communication link;

establishing a second communication link between the first terminal and the second terminal via a second network when the monitored quality of service falls below a threshold, wherein the second network excludes a circuit-switched network; and

transmitting voice information between the first terminal and the second terminal via the second communication link.

2. The method of claim 1, wherein the threshold corresponds to a measure of quality of delivered voice signals.

3. The method of claim 1, wherein establishing the second communication link occurs automatically in response to the monitored quality of service falling below the threshold.

4. The method of claim 1, further comprising transmitting a recorded voice message to the first terminal prior to establishing the second communication link.

5. The method of claim 4, further comprising receiving a response to the recorded voice message from the first terminal prior to establishing the second communication link.

6. The method of claim 1, wherein the first terminal is connected to the first communication link via a first circuit-switched network, and wherein the second terminal is connected to the first communication link via a second circuit-switched network.

7. The method of claim 6, wherein the first circuit-switched network and the second circuit-switched network are part of the Public Switched Telephone Network.

8. The method of claim 1, wherein the first terminal and the second terminal comprise telephone terminals.

9. The method of claim 1, wherein the packet switched network includes the Internet, and the second network includes the Common Channel Interoffice Switching system.

10. The method of claim 1, further comprising:

measuring a quality of service of the second network; and

establishing the second communication link when the monitored quality of service of the first communication link falls below the threshold and the quality of service of the second network is above a second threshold.

11. The method of claim 10, wherein the quality of service of the second network is based on available capacity, and the second threshold corresponds to a minimum available capacity.

12. The method of claim 1, further comprising retrieving the threshold from a record associated with a user of the first terminal.

13. The method of claim 1, wherein the first communication link uses Internet Protocol (IP) communications, and wherein establishing the first communication link comprises determining an IP address for a terminating gateway router that is connected to the packet switched network and configured to communicate with the second terminal.

14. A method, comprising:

monitoring a quality of service metric of communications over a packet switched

network, the quality of service metric including a measurement of unavailability conditions in response to a call set-up message;

transmitting a first message to a plurality of switches when the quality of service metric meets a threshold level, the first message indicating that communications may be established using the packet switched network;

setting an indication in each of the plurality of switches for the packet switched network based on the first message;

receiving at one of the plurality of switches a request to establish a voice communication between a first terminal and a second terminal;

establishing the voice communication between the first terminal and second terminal via the packet switched network when the indication is set at the one of the plurality of switches for the packet switched network; and

establishing the voice communication between the first terminal and second terminal via a second network when the indication is not set at the one of the plurality of switches for the packet switched network, wherein the second network excludes a circuit-switched network.

15. The method of claim 14, wherein monitoring the quality of service metric includes

detecting at least one unavailability message,

determining a rate of detection of the at least one unavailability message, and

comparing the rate of detection to the threshold level.

16. The method of claim 14, further comprising:

transmitting a second message to the plurality of switches when the quality of service metric does not meet the threshold level, the second message indicating that communications may be established using the second network; and

setting the indication in each of the plurality of switches for the second network based on the second message.

17. The method of claim 14, wherein the packet switched network includes the Internet, and the second network includes the Common Channel Interoffice Switching system.

18. A method, comprising:

establishing a first communication link between a first terminal and a second terminal via a packet switched network;

transmitting voice information between the first terminal and the second terminal over the first communication link;

monitoring a quality of service on the first communication link; and

establishing a second communication link between the first terminal and the second terminal via a second network when the monitored quality of service does not meet a threshold, and wherein the second network excludes a circuit-switched network.

19. The method of claim 18, wherein the threshold corresponds to a measure of quality of delivered voice signals.

20. The method of claim 18, wherein establishing the second communication link occurs automatically in response to the monitored quality of service falling below the threshold.

21. The method of claim 18, further comprising:

transmitting a recorded voice message to the first terminal when the monitored quality of service of the first communication link does not meet the threshold; and

establishing the second communication link between the first terminal and the second terminal via the second network after receiving a response to the recorded voice message from the first terminal.

22. The method of claim 18, further comprising retrieving the threshold from a record associated with a user of the first terminal.

23. The method of claim 18, wherein the first communication link uses Internet Protocol (IP) communications, and wherein establishing the first communication link comprises determining an IP address for a terminating gateway router that is connected to the packet switched network and configured to communicate with the second terminal.