Method for Analyzing Errors of a Data Stream, Particularly a Real-Time Data Stream, in a Data Network, Communication System, and Monitoring Computer

• US 20080186872A1
• Filed: 07/31/2006
• Published: 08/07/2008
• Est. Priority Date: 08/18/2005
• Status: Active Grant

• Current Assignee: VOIPFUTURE GmbH (Jan Bastian Asset Management GmbH)
• Original Assignee: VOIPFUTURE GmbH (Jan Bastian Asset Management GmbH)
• Inventors: Zaencker, Olaf Carl
• Granted Patent: US 8,885,485 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 1/205 jitter monitoring
• CPC Class Codes: H04L 1/24 Testing correct operation
• CPC Class Codes: H04L 43/045 for graphical visualisation of monitoring data
• CPC Class Codes: H04L 43/0823 Errors, e.g. transmission errors
• CPC Class Codes: H04M 2201/12 Counting circuits
• CPC Class Codes: H04M 7/0084 Network monitoring; Error detection; Error recovery; Network testing

Abstract

Disclosed is a method for analyzing errors of a data stream, particularly a real-time data stream, in a data network (100). According to said method, a time stamp and/or a sequence number is/are determined from or for each data packet transmitted between two communication terminals (10, 12) of the data network (100), a history (diagram) and/or a frequency distribution (histogram) of at least one data transmission parameter determined from the plurality of time stamps and/or sequence numbers of the data packets of the data stream is generated, and a pattern of the history and/or the frequency distribution of the at least one data transmission parameter is identified in order to determine the location and/or the cause of an error during the transmission of the data stream in the data network.

Claims

1. A method comprising receiving VoIP packets, computing interarrival times of consecutive VoIP packets, aggregating the interarrival times, and generating diagnostic data from the aggregated interarrival times, each interarrival time computed as a difference in receipt times between two consecutive packets.

2. A method according to claim 1, wherein each packet is an RTP (Realtime Transport Protocol) or RTCP (Realtime Transport Control Protocol) data packet.

3. A method according to claim 1, wherein a receipt time is indicated by a measurement timestamp.

4. A method according to claim 1, wherein the diagnostic data is based on at least one of

the variance in the latency of data packets (jitter);

packet loss; and

the time delay of a packet; and

the round-trip delay for a packet from sender to receiver and back.

5. A method according to claim 1, wherein the packets contain real voice data.

6. A method according to claim 1, wherein aggregating the interarrval times includes generating at least one of temporal progression and frequency distribution of the interarrival times.

7. A method according to claim 6, wherein generating the diagnostics data includes checking the temporal progression of at least one data transmission parameter for patterns to discern specific errors in communication between two devices.

8. A method according to claim 6, wherein the frequency distribution of at least one data transmission parameter is checked for patterns to discern specific errors in communication between two devices.

9. A method according to claim 1, wherein the diagnostic data can identity insufficient bandwidth and/or finite size of the buffer store of active network components as the cause of an error.

10. A method according to claim 1, wherein an error state in a communication between two VoIP devices is identified by recognizing patterns of the aggregated interarrival times;

and wherein an error by a sending communication device or a data transmission network is also identified by recognizing the patterns.

11. A method according to claim 10, wherein an error is determined in the sending communication device by using the pattern of the temporal progression and/or frequency distribution, a specific cause for the error is ascertainable in the sending communication device.

12. A method according to claim 11, wherein the operating system of the communication device, the configuration of the communication device, its stack or the implementation of it are ascertainable as the cause of the error.

13. A method according to claim 1, wherein determining the cause of an error includes determining whether components involved with the transmission of the data stream are able to process an RTP data packet.

14. A method according to claim 1, wherein a data stream between two communication devices is analyzed in one or both directions at one or more places of measurement.

15. (canceled)

16. An article comprising computer memory encoded with computer-readable code that causes a computer to receive VoIP packets, computer interarrival times of consecutive packets, aggregate the interarrival times, and generate diagnostic data from the aggregated interarrival times, each interarrival time computed as a difference in receipt times between two consecutive packets.

17. A communication system comprising a supervisory computer for performing error analysis of a real-time data stream between two communication devices on a data network, the computer programmed to receive VoIP packets, compute interarrival times of consecutive packets, aggregate the interarrival times, and generate diagnostic data from the aggregated interarrival times, each interarrival time computed as a difference in receipt times between two consecutive-packets.

18. (canceled)

19. (canceled)

20. A supervisory computer for error analysis of a data stream between two communication devices on a data network, the computer programmed to

obtain a timestamp from every data packet being transmitted between two communication devices on the data network;

generate at least one of a temporal progression (diagram) and/or frequency distribution (histogram) of at least one data transmission parameter, calculated from interarrival times of consecutive packets, each interarrival time computed as a difference in receipt times between two consecutive packets; and

perform pattern recognition of the temporal progression and/or the frequency distribution to diagnose a cause of an error in the transmission of the data stream on the data network.