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Integer Counter Mode

Document Type Expired Internet-Draft (cfrg RG)
Expired & archived
Author David McGrew
Last updated 2002-10-30
RFC stream Internet Research Task Force (IRTF)
Intended RFC status (None)
Additional resources Mailing list discussion
Stream IRTF state (None)
Consensus boilerplate Unknown
Document shepherd (None)
IESG IESG state Expired
Telechat date (None)
Responsible AD (None)
Send notices to (None)

This Internet-Draft is no longer active. A copy of the expired Internet-Draft is available in these formats:


This document specifies Integer Counter Mode (ICM), a mode of operation of a block cipher which defines an indexed keystream generator (which generates a keystream segment given an index). This mode is efficient, parallelizable, and has been proven secure given realistic assumptions about the block cipher. Test vectors are provided for AES. Counter Mode admits many variations. The variant specified in this document is secure and flexible, yet it enables a single implementation of a keystream generator to suffice in different application domains.


David McGrew

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)