Paper 2002/019

Scream: a software-efficient stream cipher

Shai Halevi and Don Coppersmith and Charanjit Jutla

Abstract

We report on the design of Scream, a new software-efficient stream cipher, which was designed to be a ``more secure SEAL''. Following SEAL, the design of Scream resembles in many ways a block-cipher design. The new cipher is roughly as fast as SEAL, but we believe that it offers a significantly higher security level. In the process of designing this cipher, we re-visit the SEAL design paradigm, exhibiting some tradeoffs and limitations.

Note: some typos in the pseudocode were corrected