초록 ▼

In order to transparently redirect an HTTP connection request that is directed to an origin server (107) to a proxy cache (110-1), a proxy redirector (104) translates the destination address of packets directed to the origin server to the address of the proxy. During a handshaking procedure, a TCP c

In order to transparently redirect an HTTP connection request that is directed to an origin server (107) to a proxy cache (110-1), a proxy redirector (104) translates the destination address of packets directed to the origin server to the address of the proxy. During a handshaking procedure, a TCP connection is transparently established between the client (110-1) and the proxy cache. When the client transmits a GET request to what it thinks is the origin server, which request specifies the complete address of an object at that origin server that it wants a copy of, the proxy redirector modifies the complete address specified in that GET request before it is sent to the proxy cache. Specifically, the IP address of the origin server found in the destination field in the IP header of the one or more packets from the client containing the GET request is added by the proxy redirector as a prefix to the complete URL in the GET request to form an absolute URL. The proxy cache determines from that absolute URL whether it has the requested object stored in its cache. If it does, it sends the object back to the proxy redirector, which masquerades those packets as coming from the origin server by translating their destination address to the address of the client and their source address to that of the origin server. If the proxy does not have the requested object, a separate TCP connection is established between the proxy and the origin server from where the object is retrieved and then forwarded over the TCP connection between the client and the proxy. In order to account for the additional number of bytes in the GET request, an acknowledgement sequence number in packets returned from the proxy that logically follow receipt of the GET request are decremented by that number by the proxy redirector before being forwarded to the client. Similarly, a sequence number in packets transmitted by the client subsequent to the GET request are incremented by that number before being forwarded by the proxy redirector to the proxy cache.

대표청구항 ▼

1. A method at a Layer 4 switch for redirecting an HTTP connection request from a client that is directed to an origin server to a proxy cache over a packet-based computer network comprising the steps of:receiving at least one packet containing a request message within the HTTP connection, the at le

1. A method at a Layer 4 switch for redirecting an HTTP connection request from a client that is directed to an origin server to a proxy cache over a packet-based computer network comprising the steps of:receiving at least one packet containing a request message within the HTTP connection, the at least one packet having an IP header comprising a destination address of an origin server, the request message including a complete address of a specified object at the origin server; modifying, at the packet level, the request message by combining the destination address of the origin server with the complete address; and forwarding the at least one packet containing the modified request message to the proxy cache over the packet-based network; wherein the proxy cache is a standard proxy cache and, in the forwarding step, the at least one packet containing the modified request is redirected to the standard proxy cache transparently from the standpoints of both the client and the proxy cache, the proxy cache being able to determine whether it can satisfy the request for the specified object by using the combined destination address of the origin server and the complete address contained in the modified request message.