Caching and streaming of digital media content subsets

A cache node comprising:

• a communication interface configured to exchange data over a network;
• a nonvolatile storage medium;
• a processing system configured to:
• receive a request, via the communication interface, from an end user device for a selected portion of digital media content in a first format;
• responsive to the request from the end user device, identify an origin server acting as a persistent storage location for an original media file comprising the selected portion of digital media content;
• retrieve, via the communication interface, a header corresponding to the original media content, the header comprising metadata for the original media file;
• identify an origin format of the original media file from the header;
• process the header portion to identify a byte range of the digital media content corresponding to the selected portion;
• retrieve the selected portion from the origin server using the byte range;
• transmux the selected portion of the digital media content from the origin format into the first format;
• providing the selected portion to the end user device in the first format via the communication interface;
• store the selected portion in the first format to the nonvolatile storage medium;
• receive a subsequent request, via the communication interface, for the selected portion in a second format;
• transmux a copy of the selected portion from the nonvolatile storage medium from the first format to the second format;
• provide the content in the second format in response to the subsequent request;
• and
• store the selected portion in the second format to the nonvolatile storage medium.

A data storage device storing instructions that, when executed, cause a processor to perform a method comprising:

• operating a cache node of a content distribution network, including:
• receiving a request from an end user device for a selected portion of digital media content in a first format;
• responsive to the request from the end user, identifying an origin server acting as a persistent storage location for an original media file comprising the selected portion of digital media content;
• retrieving a header corresponding to the original media file, the header comprising metadata for the original media file;
• identifying an origin format of the original media file at least from the header;
• processing the header portion to identify a byte range of the digital media content corresponding to the selected portion;
• retrieving the selected portion from the origin server using the byte range;
• responsive to the request from the end user device, transmuxing the selected portion of the digital media content from the origin format into the first format and providing the selected portion to the end user device in the first format;
• storing the selected portion in the first format to a cache memory of the cache node;
• receiving a subsequent request for the selected portion in a second format;
• transmuxing a copy of the selected portion from the cache memory from the first format to the second format and providing the content in the second format in response to the subsequent request;
• and
• storing the selected portion in the second format to the cache memory.