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. As used herein, this routing through an intermediate server, node or region is sometimes referred to as “tunneling.”