HTTP based adaptive streaming technologies such as Microsoft's Smooth streaming, Apples HLS or Adobes HDS use multiple files for the same content, allowing the client, normally a browser, to chose and change the quality of the feed based on local conditions such as connection speeds and CPU load.
The client can request a change in the bit rate being delivered if local conditions change.
The feed can be live or on-demand.

Currently neither SGOS 6.5 nor SGOS 6.6 support pre-population of adaptive streaming media files.This is being looked at for future versions of SGOS

The ProxySG can however cache this content, with significant savings however it may require creating specific code to get this to work correctly. see article 000027766 for more details