Using entity tags (ETags) in a hierarchical HTTP proxy cache to reduce network traffic

摘要

Disclosed is a program for validating a web cache independent of an origin server. A computer in between a client computer and the origin server computer receives a request for a resource and an entity tag (ETag) corresponding to the request. The computer forwards the request to the origin server and subsequently receives the resource. The computer generates an ETag for the received resource and compares the generated ETag to the ETag corresponding to the request. If the ETags match, the computer sends an indication toward the client computer that the resource has not been modified.