Auto latency test tool

• US 6,594,344 B2
• Filed: 12/28/2000
• Issued: 07/15/2003
• Est. Priority Date: 12/28/2000
• Status: Expired due to Fees

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Intel Corporation
• Inventors: Masri, Ahmad, Wilson, Steven J., Nice, Nir
• Primary Examiner(s): Tieu, Binh
• Assistant Examiner(s): Taylor, Barry W
• Application Number:
  US09/749,610
• Publication Number:
  US 20020085683A1
• Time in Patent Office: 929 Days
• Field of Search: 379/10.01, 379/10.02, 379/10.03, 379/27-1-, 379/22.02
• US Class Current: 379/27.01
• CPC Class Codes: H04L 43/0852 Delays
• CPC Class Codes: H04L 43/12 Network monitoring probes
• CPC Class Codes: H04M 3/22 Arrangements for supervision, monitoring or testing
• 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

Abstract

A system and method for measuring latency in voice communications is presented. In an exemplary embodiment, latency is measured by establishing a call between a first and a second telephony device, and measuring a latency between a signal originating at the first telephony device and the signal as it arrives at the second telephony device.

Claims

1. A method of measuring latency in a VoIP (Voice over Internet Protocol) network, comprising:

establishing a call between a first telephony device and a second telephony device;

exchanging, over a VoIP network, one or more signals between the telephony devices;

measuring a baseline latency between at least one signal originating at the first telephony device and the signal as it arrives at the second telephony device,

wherein the baseline latency is measured with a waveform analysis mechanism configured to monitor the at least one signal originating at the first telephony device and the signal as it arrives at the second telephony device,

wherein the waveform analysis mechanism comprises an oscilloscope, the oscilloscope being a standalone device removably connected to the first telephony device and the second telephony device, the oscilloscope monitoring the signal originating at the first telephony device and the signal as it arrives at the second telephony device;

establishing at least one additional call;

measuring, with the oscilloscope, a second latency between a second signal originating at the first telephony device and the second signal as it arrives at the second telephony device when the at least one additional call is established; and

comparing the baseline latency with the second latency.

2. The method according to claim 1, wherein the first telephony device is a telephony card.

3. The method according to claim 1, wherein the first telephony device is a telephone.

4. The method according to claim 1, further comprising establishing a plurality of additional calls, each of the additional calls being established between a pair of telephony devices.

5. The method according to claim 1, wherein the first and the second telephony devices are each coupled to a data bus in one computer.

6. The method according to claim 1, wherein the network includes an internet.

7. The method according to claim 1, wherein the network includes an ISDN network.

8. A system to measure latency in a VoIP (Voice over Internet Protocol) network, comprising:

a computer having a data bus;

a first and a second telephony device, the telephony devices being coupled to the data bus over a VoIP network and configured to transmit to each other and receive from each other signals;

a monitoring device coupled to the data bus and configured to monitor calls between the telephony devices;

an oscilloscope having a first and a second probe removably coupled to the monitoring device, the oscilloscope being a standalone device, the first probe being arranged to sense a signal originating at the first telephony device, the second probe being arranged to sense the signal as it arrives at the second telephony device, the oscilloscope displaying a phase difference between the originating and arriving signals, the phase difference representing a baseline latency; and

a call generator coupled to the first and the second telephony devices, the call generator being configured to establish at least one call between the telephony devices,

wherein the baseline latency is compared with a second latency measured by the oscilloscope, the second latency being measured when at least one additional call is established by the call generator, the second latency being between a second signal originating at the first telephony device and the second signal as it arrives at the second telephony device when the at least one additional call is established.

9. The system according to claim 8, wherein the telephony devices are analog telephony cards.

10. The system according to claim 8, wherein the telephony devices are digital telephony cards.

11. The system according to claim 8, further comprising a first and a second telephone, the first telephone being coupled to the monitoring device and being associated with the first telephony device, the second telephone being coupled to the monitoring device and being associated with the second telephony device.

12. The system according to claim 11, wherein a handset of either of the telephones is configured to be lifted to monitor the calls.

13. The system according to claim 8, wherein the call generator includes a bulk call generator program.