Staggered Stripping For Multimedia Servers
Tech ID: 20323 / UC Case 1995-524-0
Multimedia information systems have emerged as an essential component of many application domains ranging from library information systems to entertainment technology. This invention consists of a data layout and associated scheduling algorithm that support the continuous display of multimedia objects and eliminate the frequent disruptions and delays that are termed hiccups. This method accommodates objects with different delivery rates (MPEG-1, MPEG-2, uncompressed, etc.) and also handles multiple requests for the same or different objects. A wide range of bandwidths of objects can be handled easily (from sub-disk bandwidth to objects requiring the bandwidth of a number of disks). This method, which is entitled staggered stripping, will provide effective support for multiple users accessing the different objects in the database . It consists of allocating continuous media objects to a parallel collection of rotating storage devices such that: (a) the fetch of an object can be accomplished at a predefined rate (bytes/sec) that matches the desired delivery rate for the object, (b) at each instant only a subset of the storage device is used for a particular request for an object, (c) the exact subset of storage devices being used for a particular request changes over time in such a way that the request presents a balanced load across all of the storage devices, and (d) the allocation and scheduling scheme can accommodate a wide range of required object delivery rates without incurring collisions between requests. In staggered stripping, the exact method of stripping is a function of the object bandwidth requirement. Finally, this method of allocation enables a very efficient and simple scheduling algorithm.
|United States Of America||Issued Patent||5,799,174||08/25/1998||1995-524|
- Muntz, Richard R.
digital mediacommunications and Optimization