Method and apparatus for using client puzzles to protect...

Details Method and apparatus for using client puzzles to protect... Method and apparatus for using client puzzles to protect...

2005-09-13

2005-09-13

Lim, Krisna (Department: 2153)

Electrical computers and digital processing systems: multicomput

Computer network managing

Computer network access regulating

C709S227000, C713S152000

Reexamination Certificate

active

06944663

ABSTRACT:
One embodiment of the present invention provides a system that protects a server against denial-of-service attacks. During operation, the server receives a request for service from a client. Note that the client can be distinguished from other clients, for example, by its source IP address. In response to this request, the server sends a random number, y, and an identifier, id1, to the client, and allows the client to compute a preimage, x, such that y=h(x). Upon receiving an answer from the client including the preimage x and an identifier, id2, the server verifies that the identifier, id1, sent to the client matches the identifier, id2, received from the client. If the identifiers match, the server computes h(x), and compares h(x) against y. If h(x)=y, the server performs the requested service for the client. In this way, the server avoids computing h(x) until the server receives the answer with a matching identifier.

REFERENCES:
patent: 5826014 (1998-10-01), Coley et al.
patent: 6738814 (2004-05-01), Cox et al.
patent: 6751668 (2004-06-01), Lin et al.
patent: 6772334 (2004-08-01), Glawitsch
patent: 6775704 (2004-08-01), Watson et al.
patent: 6789203 (2004-09-01), Belissent
patent: 6823387 (2004-11-01), Srinivas
patent: 6851062 (2005-02-01), Hartmann et al.
Publication entitled “Using Client Puzzles to Protect TLS,” by Drew Dean and Adam Stublefield, proceedings of the 10thUsenic Security Symposium, Washington, D.C., USA, pp. 1-8, Aug. 2001.

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