BIG-IP® video delivery optimization provides you with the ability to retrieve and accelerate on-demand video stream from an origin web server. The BIG-IP system sends client requests for the video stream to an origin web server, caches the response video segments, and sequentially sends optimized video responses to all authorized users.
Additionally, video delivery optimization enables you to associate video advertisements with a video stream, providing the ability to preroll advertisements, or to insert advertisements as specified by a video advertisement policy.
You can configure BIG-IP® devices in asymmetrical deployments, symmetrical deployments, or both to optimize performance needs, positioning BIG-IP devices in accordance with higher-demand, lower-bandwidth locations within the network.
A BIG-IP® device manages popular video content by evaluating several aspects, including the proximity of clients, number of requests, performance of the network, and defining values of the video segments. You can modify the resultant evaluation by changing the Cache Priority setting in the Responses Cached screen for a BIG-IP acceleration policy.
You can define a caching priority level for video segments, which is useful in specifying a higher caching priority for popular video segments, by using the Cache Priority setting in the Responses Cached screen.
Optimizing video in a global network improves the video performance across significant distances. When you implement video delivery optimization in a symmetric deployment, the system caches video segments on the device closest to the client, reducing the latency and improving the quality of the video.
You can specify a maximum bit rate for video delivery optimization, which limits the maximum bit rate that is available to the user. When you configure different maximum bit rates, you can designate those specific bit rates to different types or levels of users. For example, you could create a policy node for each level of user and assign a different maximum bit rate to each node. A value of 0 indicates that the bit rate is unconstrained.
The BIG-IP® system's video Quality of Experience (QoE) profile enables you to assess an audience's video session or overall video experience, providing an indication of customer satisfaction. The QoE profile uses static information, such as bitrate and duration of a video, and video metadata, such as URL and content type, in monitoring video streaming. Additionally, the QoE profile monitors dynamic information, which reflects the real-time network condition.
By considering both the static video parameters and the dynamic network information, the user experience can be assessed and defined in terms of a single mean opinion score (MOS) of the video session, and a level of customer satisfaction can be derived. QoE scores are logged in the ltm log file, located in /var/log, which you can evaluate as necessary.
Note that for QoE to properly process video files, the video web servers must be compliant with supported video MIME types, for example, the following MIME types.
The video Quality of Experience (QoE) profile provides a mean opinion score (MOS), derived from static and dynamic parameters associated with a video stream. The following table summarizes the resultant values.
|5||Excellent||Indicates a superior level of quality, with imperceptible degradation in the video stream.|
|4||Good||Indicates an above-average level of quality, with perceptible degradation that is acceptable.|
|3||Fair||Indicates an average level of quality, with perceptible degradation that detracts from the video experience.|
|2||Poor||Indicates a below-average level of quality, with perceptible degradation that significantly detracts from the video experience.|
|1||Bad||Indicates a substandard level of quality, with perceptible degradation that proves to be significantly inferior and potentially unacceptable.|