Patent ID: 7836295

Claim:
A method for improving the resilience of a content distribution network (CDN) to distributed denial of service (DDoS) attacks, comprising: sending, from a client to a router, a request to access a web site that is hosted by at least one of a plurality of servers in the CDN, the request including a source address of the client and a site address of the web site; hashing, at the router, the source address and the site address with a hash function that is shared between the router and the servers to obtain an address of one of the servers that hosts the web site; sending, from the router to the client, the address of one of the servers that hosts the web site; sending, from the client to the server with the address, a request for content of the web site, the request including the source address and the site address; hashing, at the server, the source address and the site address with the shared hash function to obtain a hash value, wherein the request is inserted into a normal queue in response to the hash value matching the address of the server, and the request is inserted into a low priority queue in response to the hash value not matching the address of the server; and sending, from the server to the client, the requested content in response to the request being inserted into the normal queue.