The goal of caching within the DME and a DME network is to allow a viewer to locate and playback content hosted by any (with reachability) DMEs. Set up will depend on the deployment used:

The caching system on the DME, which is independent from the content directories, is stored either in Memory or on Disk. These caches are maintained, and content is aged out by the caching system.

Depending upon your specific needs for this particular DME, you may wish to increase or decrease the caching capabilities. Specifically, you can control how much memory and disk the caching system can utilize. These settings control only HTTP based protocol caching (which includes progressive mp4, HLS and HDS delivery). Each of these settings will also have an impact on the amount of available storage for VOD content. Further, extensive use of the CPU will have a trade-off effect with other CPU intensive features (like transrating). As such, High or Dedicated settings should only be used on DMEs that will be used as reflectors or purely caching. DMEs that are used as prepositioned content servers should be set with Normal to Low caching settings.

This setting is unique to each of your DMEs within your deployment. As an example, it may be, based on your deployment architecture, that a few edge DMEs will be set as High Caching to facilitate remote reflection, while larger content DMEs may be set for Normal or Low. Please consider this setting during your deployment architecture design.

The table below defines the memory and disk usage by level. These measurements are consistently applied across all DME versions. i.e., Large DMEs set to High or Dedicated will use that much memory, if available. The percentages may be set on the System Configuration > Streaming page in the Cache System Resources Used drop-down.