Patent · US Expired

Method and apparatus for caching a media stream

US6463508B1 · kind B1 · utility

217Cited by
6References
47Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 19, 1999
Grant dateOct 8, 2002
Priority date
Expiry dateJul 19, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L67/563
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A system and method for caching media streams at proxy servers. In the current invention, blocks received for a media stream are grouped into segments by the proxy servers, where the cache admission and replacement policies attach a different caching value to different segments, taking into account the segment distance to the start of the media object. These policies give preferential treatment to the beginning segments and may take into account other considerations such as the media object reference frequency, time since the last reference to the object, or its access time. According to the invention, the proxy server is enabled to cache a subset of the segments, which will generally be the beginning segments. According to another aspect of the invention, if only a portion of a media stream is cached in the proxy server when the stream is requested, the remaining segments are prefetched. Thus, upon receipt of a media request, the proxy can immediate serve the request using the segments cached, and compose and issue a prefetch request to obtain the remaining blocks for segments which are not currently cached.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.