(12) United States Patent ao) Patent No.: Us 7,929,429 B2
Bornstein et al. (45) Date of Patent: *Apr. 19,2011
FOREIGN PATENT DOCUMENTS
WO WO0060861 1/2000
Wessels et al, Internet Cache Protocol (ICP), Version 2, Internet
Request for Comment (RFC) 2186, Sep. 1997.
Primary Examiner — Chi H Pham
Assistant Examiner — Alexander Boakye
(74) Attorney, Agent, or Firm — David H. Judson
A routing mechanism, service or system operable in a distributed networking environment. One preferred environment is a content delivery network (CDN) wherein the present invention provides improved connectivity back to an origin server, especially for HTTP traffic. In a CDN, edge servers are typically organized into regions, with each region comprising a set of content servers that preferably operate in a peer-to-peer manner and share data across a common backbone such as a local area network (LAN). The inventive routing technique enables an edge server operating within a given CDN region to retrieve content (cacheable, non-cacheable and the like) from an origin server more efficiently by selectively routing through the CDN's own nodes, thereby avoiding network congestion and hot spots. The invention enables an edge server to fetch content from an origin server through an intermediate CDN server or, more generally, enables an edge server within a given first region to fetch content from the origin server through an intermediate CDN region.
10 Claims, 4 Drawing Sheets
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