Triple-Play Service Deployment

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Troubleshooting Video Service in the Field
Video service quality is ultimately determined by the end user or
subscriber. The quality of experience (QoE) is a subjective concept
components that are nearly impossible to measure in a practical,
operational manner. Yet, a service provider can make objective
measurements on a set of parameters that can be used to judge
the performance of the network. A model for mapping objectively
measurable metrics to QoE is the basis for good installation and
troubleshooting procedures.
Mapping of objective measures of quality for video services—
video quality of service (QoS) parameters—cannot be made in a
one-to-one, direct correlation manner, nor can all subjective issues
be measured directly. This is true especially of certain video
artifacts which may be present in the video payload. In order to
help with this correlation and add structure to measurement
approaches, quality in this context can be organized into a logical
model with four parts:
– Content Quality: the actual video and audio payload
– Video Stream Quality: the video transport stream packet flows
– Transport Quality: the IP packet flows
– Transactional Quality: the interaction between the user and the
service
Components of the Video Quality Experience
The video quality experience includes transactional items and
program content specific items. Transaction items include the
availability of program material, responsiveness of the electronic
program guide (EPG), video on demand (VoD) billing transaction
delay, channel change delay, and VoD feature responsiveness to
pause/play commands. Program content items encompass picture
quality and audio quality, including the absence of blurred images,
edge distortion, pixelization, tiling, or frozen frames.