Apparatus and method for call progress timing measurement in IP telephony

• US 6,411,679 B1
• Filed: 09/17/1999
• Issued: 06/25/2002
• Est. Priority Date: 09/17/1999
• Status: Expired due to Term

• Current Assignee: Verizon Laboratories Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Laboratories Incorporated (Verizon Communications Inc.)
• Inventors: Khasnabish, Bhumip
• Primary Examiner(s): TIEU, BINH KIEN
• Application Number:
  US09/398,185
• Time in Patent Office: 1,012 Days
• Field of Search: 379/111, 379/113, 379/114, 379/115, 379/133, 379/135, 379/372, 379/399, 379/34, 379/134, 379/1.01, 379/9, 379/9.01, 379/14, 379/10.02, 379/15.01, 379/22.02, 379/283, 379/286, 370/241, 370/242, 370/244, 370/249, 370/250, 370/252
• US Class Current: 379/9
• CPC Class Codes: H04M 1/24 Arrangements for testing
• CPC Class Codes: H04M 3/323 for the arrangements providing the connection (test connection, test call, call simulation)
• CPC Class Codes: H04M 7/1205 where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks

Abstract

A method and apparatus for measuring call setup time is presented. A first device in a network sends a signal to a second device. The first device monitors for a response from the second device and adjusts an answer tone setting for the second device based on the response. After which, the first device calculates an elapsed time between sending the signal and a receipt of the response.

Claims

1. A method performed by a first device connected to a network for measuring call setup time, comprising:

sending a signal to a second device;

monitoring for an expected response from the second device;

repeatedly adjusting, when a vender specific tone is detected from the second device, an answer tone setting for the second device by changing at least one of an upper and lower bound frequency of a dual tone multi-frequency (DTMF) tolerance or altering a response detection window size until receipt of the expected response; and

calculating an elapsed time between sending the signal and a receipt of the expected response.

2. The method of claim 1, wherein said signal is a call originating gateway phone number.

3. The method of claim 1, wherein said signal is a user-id.

4. The method of claim 1, wherein said signal is a user authentication number.

5. The method of claim 1, wherein said signal is a destination telephone number.

6. The method of claim 1, wherein said calculating step further comprises:

reading a time stamp associated with the sending of the signal;

reading a time stamp associated with a receipt of the response; and

subtracting the time stamp associated with the sending the signal from the time stamp associated with the receipt of the response.

7. A tester for measuring call setup time comprising:

means for sending a signal to a device;

means for monitoring for an expected response from the device;

means for repeatedly adjusting, when a vender specific tone is detected from the second device, an answer tone setting for the second device until receipt of the expected response, wherein the means for adjusting includes at least one of means for changing an upper and lower bound frequency of a dual tone multi-frequency (DTMF) tolerance and means for altering a response detection window size; and

means for calculating an elapsed time between sending the signal and a receipt of the expected response.

8. The tester of claim 7, wherein said signal is a call originating gateway phone number.

9. The tester of claim 7, wherein said signal is a user-id.

10. The tester of claim 7, wherein said signal is a user authentication number.

11. The tester of claim 7, wherein said signal is a destination telephone number.

12. The tester of claim 7, wherein said means for calculating further comprises:

means for reading a time stamp associated with the sending of the signal;

means for reading a time stamp associated with the receipt of the response; and

means for subtracting the time stamp associated with the sending of the signal from the time stamp associated with the receipt of the response.

13. A tester for measuring call setup time, comprising:

a memory having program instructions; and

a processor responsive to the program instructions to;

send a signal to a device, monitor for an expected response from the device;

repeatedly adjust, when a vender specific tone is detected from the second device, an answer tone setting for the second device until receipt of the expected response, wherein the adjusting includes at least one of changing an upper and lower bound frequency of a dual tone multi-frequency (DTMF) tolerance and altering a response detection window size; and

calculate an elapsed time between sending the signal and a receipt of the expected response.

14. A system for measuring call setup time, comprising:

a circuit-switched network;

a packet network;

at least one gateway connecting the circuit-switched network to the packet network, the gateway operable to transfer information between the circuit-switched network and the packet network; and

a tester connected to the circuit-switched network, the tester operable to place a telephone call over the packet network, wherein when the tester initiates a telephone call over a packet network, the tester sends a signal to a device, monitors for an expected response from the device, repeatedly adjusts an answer tone setting for the device until receipt of the expected response, and calculates an elapsed time between sending the signal and a receipt of the expected response.