Multi-user, on-demand video server system including independent, concurrently operating remote data retrieval controllers

A method for actively retrieving data from storage, comprising:

• storing data in a storage;
• providing a plurality of data retrieval controllers connected to the storage, each of the data retrieval controllers being capable of actively retrieving data from the storage and converting the retrieved data to a predetermined format;
• converting data, in a download computer, from analog form into compressed digital format to be stored in the storage;
• receiving and processing, in the download computer, data request commands;
• sending, in response to the data request commands, designation commands from a server to the data retrieval controllers, each designation command designating one of the data retrieval controllers and a storage location corresponding to requested data to be retrieved from the storage by the designated data retrieval controller;
• retrieving by the respective designated data retrieval controllers requested data corresponding to the designated storage locations using read commands;
• producing each retrieved data in a predetermined format at an output of the respective designated data retrieval controller;
• and
• sending to the server by the respective designated data retrieval controllers a message indicating that execution of each corresponding designation command has been completed.

A video server system, comprising:

• a mass storage unit in which a plurality of movies are distributively stored in digital form such that the movies can be viewed on-demand by multiple users;
• a download computer capable of converting movie data received in analog form into compresses digital format to be stored in the mass storage unit as well as receiving from interactive remote control units and processing movie requests;
• a server configured to receive processed movie requests from the download computer and, in response to each movie request, generate designation commands;
• a plurality of retrieval controllers connected to the server via a SCSI bus to receive therefrom the designation commands, each of the designating commands designating one of the retrieval controllers and a storage location corresponding to requested movie data, each of the designated retrieval controllers retrieving the requested movie data from the mass storage unit via the SCSI bus by sending read commands to the mass storage, each of the designated the retrieval controllers also sending messages to the server indicating that execution of the respective designation commands has been completed.

A method for providing video on-demand, comprising:

• distributively storing data of a plurality of movies in a mass storage having drives, the data stored across the drives in a stripped arrangement so that each strip includes a plurality of successive bytes that are stored in a same location in the drives, respectively;
• storing in one of the drives a parity byte corresponding to each of the strips for malfunction detection and recovery;
• synchronously controlling the drives by a master controller;
• converting in a download computer movie data received in an analog form into compressed digital format to be stored in the mass storage, the converted movie data being delivered to the mass storage via a server that is linked to the down load computer by a SCSI interface;
• receiving and processing at the download computer requests for selected movies from among the plurality of movies, and sending the processed requests to a server;
• producing at the server a list of data locations in the drives for each selected movie and sending a succession of SCSI designation commands to retrieval controllers designating the respective retrieval controllers and data locations for each selected movie;
• sending read commands from each designated retrieval controller;
• and
• converting data retrieved from the drives into formats suitable for respective user receivers.