Method and system to identify a network device associated with poor QoS

Abstract

A method and apparatus to analyze real-time data transmissions across a network is described. The method may comprise transmitting a sample data stream between source and destination endpoints across a test data path which includes network devices. The method may then compare a measured quality of the received sample data stream with pre-defined quality criteria associated with the network. If the measured quality fails to meet the pre-defined quality criteria, the network devices in the test data path may be identified, device performance data may be obtained, and a network report may be generated based on the device performance data. The device performance data may comprise processor utilization, memory utilization, bandwidth over subscription, buffer over run, and/or a number of non-error packets that are discarded at the network device.

What is claimed is: 
     
       1. A method comprising:
 transmitting a sample data stream at a known first quality in a network between a source endpoint and a destination endpoint across a test data path that includes at least two network devices, at least one of the two network devices being a WAN edge router that lies between the source endpoint and the destination endpoint in the test data path; 
 comparing a measured second quality of the received sample data stream with the known first quality of the transmitted sample data stream; 
 determining that the measured second quality is less than the known first quality; and 
 in response to the determination that the measured second quality fails to meet the known first quality, performing operations including:
 identifying at least one network device in the test data path; 
 obtaining device performance data of the at least one network device, wherein the device performance data of the WAN edge router is obtained from an interface of the WAN edge router; 
 using the device performance data of the WAN edge router to determine if the WAN edge router is contributing to the failure of the measured second quality to meet the known first quality; and 
 generating a network report based on the device performance data, the network report relating the at least one device in the test data path to a failure of the measured second quality to meet the known first quality. 
 
 
     
     
       2. The method of  claim 1 , wherein the device performance data includes at least one of processor utilization, memory utilization, bandwidth oversubscription, buffer overrun, or a number of non-error packets that are discarded due to buffer overrun. 
     
     
       3. The method of  claim 1 , further comprising:
 monitoring a plurality of network devices to obtain corresponding performance data prior to transmitting the sample data stream; 
 identifying the at least one network device in the test data path from the monitored network devices; and 
 obtaining the device performance data of the at least one network device in the test data path from the performance data obtained prior to transmitting the sample data stream. 
 
     
     
       4. The method of  claim 1 , wherein the operations performed in response to the determination that the measured second quality fails to meet the known first quality criteria include:
 interrogating a WAN edge router in the test data path to obtain device performance data for the WAN edge router. 
 
     
     
       5. The method of  claim 1 , wherein the sample data stream includes a voice data stream. 
     
     
       6. A non-transitory machine-readable storage medium storing instructions that, when executed by a machine, cause the machine to perform operations comprising:
 transmitting a sample data stream at a known first quality in a network between a source endpoint and a destination endpoint across a test data path that includes at least two network devices, at least one of the two network devices being a WAN edge router that lies between the source endpoint and the destination endpoint in the test data path; 
 comparing a measured second quality of the received sample data stream with the known first quality of the transmitted sample data stream; 
 determining that the measured second quality fails to meet the known first quality; and 
 in response to the determination that the measured second quality fails to meet the known first quality, performing operations including:
 identifying at least one network device in the test data path; 
 obtaining device performance data of the at least one network device, wherein the device performance data of the WAN edge router is obtained from an interface of the WAN edge router; 
 using the device performance data of the WAN edge router to determine if the WAN edge router is contributing to the failure of the measured second quality to meet the known first quality; and 
 generating a network report based on the device performance data, the network report relating the at least one device in the test data path to a failure of the measured second quality to meet the known first quality. 
 
 
     
     
       7. The non-transitory machine-readable storage medium of  claim 6 , wherein the device performance data includes at least one of processor utilization, memory utilization, bandwidth oversubscription, buffer overrun, or a number of non-error packets that are discarded due to buffer overrun. 
     
     
       8. The non-transitory machine-readable storage medium of  claim 6 , wherein instructions further cause the machine to perform operations comprising:
 monitoring a plurality of network devices to obtain corresponding performance data prior to transmitting the sample data stream; 
 identifying the at least one network device in the test data path from the monitored network devices; and 
 obtaining the device performance data of the at least one network device in the test data path from the performance data obtained prior to transmitting the sample data stream. 
 
     
     
       9. The non-transitory machine-readable storage medium of  claim 6 , wherein the operations performed in response to the determination that the measured second quality fails to meet the known first quality include:
 interrogating a WAN edge router in the test data path to obtain device performance data for the WAN edge router. 
 
     
     
       10. The non-transitory machine-readable storage medium of  claim 6 , wherein the sample data stream includes a voice data stream. 
     
     
       11. An apparatus comprising:
 a network interface unit configured to enable communications over a network; and 
 a processor configured to:
 transmit a sample data stream at a known first quality in the network between a source endpoint and a destination endpoint across a test data path that includes at least two network devices, at least one of the two network devices being a WAN edge router that lies between the source endpoint and the destination endpoint in the test data path; 
 compare a measured second quality of the received sample data stream with the known first quality of the transmitted sample data stream and to determine that the measured second quality fails to meet the known first quality; 
 identify at least one network device in the test data path; 
 obtain device performance data of the at least one network device, wherein the device performance data of the WAN edge router is obtained from an interface of the WAN edge router; 
 use the device performance data of the WAN edge router to determine if the WAN edge router is contributing to the failure of the measured second quality to meet the known first quality; and 
 generate a network report based on the device performance data, the network report relating the at least one device in the test data path to a failure of the measured second quality to meet the know first quality. 
 
 
     
     
       12. The apparatus of  claim 11 , wherein the device performance data includes at least one of processor utilization, memory utilization, bandwidth oversubscription, buffer overrun, or a number of non-error packets that are discarded due to buffer overrun. 
     
     
       13. The apparatus of  claim 11 , wherein the processor is further configured to:
 monitor a plurality of network devices to obtain corresponding performance data prior to transmitting the sample data stream, 
 identify the at least one network device in the test data path from the monitored network devices, and 
 obtain the device performance data of the at least one network device in the test data path from the performance data obtained prior to transmitting the sample data stream. 
 
     
     
       14. The apparatus of  claim 11 , wherein the processor is further configured to interrogate a WAN edge router in the test data path to obtain device performance data for the WAN edge router.