Secure Applications of Low-Entropy Keys

J. Kelsey, B. Schneier, C. Hall, and D. Wagner

1997 Information Security Workshop (ISW'97), September 1997, pp. 121-134.

ABSTRACT: We introduce the notion of key stretching, a mechanism to convert short s-bit keys into longer keys, such that the complexity required to brute-force search a (s+t)-bit keyspace is the same as the time required to brute-force search a s-bit key stretched by t bits.

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