Troubleshooting Quality of Service (QoS) and Quality of Experience (QoE) Issues in Video Service Provider Networks

Quality of Service and Quality of Experience: Learn the benefits and faults of the two most common test methods for troubleshooting video signal problems and the critical capabilities required in an MPEG analyzer.

Video Service Providers deliver TV programs using a variety of different network architectures. Most of these networks include satellite for distribution (ingest), ASI or IP throughout the facility, and often RF to the home or customer premise (egress). The quality of today’s digital video and audio is usually quite good, but when audio or video issues appear at random, it is usually quite difficult to pinpoint the root cause of the problem. The issue might be as simple as an encoder over-compressing a few pictures during a scene with high motion. Or, the problem might be from a random weather event (e.g., heavy wind, rain, snow, etc.). In some cases, it is as simple as adding too many 3 dB RF splitters in the home.

No matter where the problem comes from, it is important to be able to quickly identify and log the audio or video problem that occurred, then identify or pinpoint the equipment (or network link) that needs attention. To identify and isolate problems, it is critical to have access or test points throughout the facility.
The minimum set of test points in any network should be at the point of ingest where the signal comes into the facility, the ASI or IP switch, and finally egress where the signal leaves as IP or RF. With a minimum of these three access points, it is now possible to isolate the issue to have originated at either: ingest, facility, or egress.

To begin testing a signal that may contain the suspected issue, two related methods are often used, Quality of Service (QoS), and Quality of Experience (QoE). Both methods are useful in troubleshooting and analysis, but each of the two methods quantify issues using completely different metrics.

This application note will focus on both types of testing methods using the Tektronix MTS4000 MPEG Analyzer, and will explain the benefits and faults with each type.