Patent ID: 6205481
Filing Date: 2001-03-20
Classification: G06F,H04L

Abstract:
In a system containing a plurality of computers which communicate over a network using communication protocols, with the computers at certain nodes in the network acting as home servers, for storing information in the form of documents, and with certain other computers acting as clients that send document request messages to the servers at an application layer, the document request messages being requests for documents stored at the servers, a method of maintaining copies of documents at the intermediate nodes comprising the steps of:(a) storing local cache copies of documents at a plurality of intermediate node locations in the network;(b) in response to a particular one of the clients generating a particular document request message intended to be sent to a particular one of the home servers, fulfilling the document request message at one of the intermediate node locations by intercepting the document request message and returning one of the local cache copies to the client;(c) determining the identity of at least one neighboring intermediate node that stores local cache copies; and(d) determining if a local cache copy of a requested document is different from a copy of the requested document at the home server;wherein step (d) further comprises the steps of:i) forwarding a hit report to a home server after fulfilling the document request message at one of the intermediate node locations; andii) receiving a reply from the home server indicating a time of last modification of the requested document.