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This draft is a work item of the S/MIME Mail Security Working Group of the IETF.
Title : Methods for Avoiding the 'Small-Subgroup'
Attacks on the Diffie-Hellman Key Agreement Method
Author(s) : R. Zuccherato
Filename : draft-ietf-smime-small-subgroup-00.txt
Pages : 7
Date : 26-Mar-99
In some circumstances the use of the Diffie-Hellman key agreement scheme
in a prime order subgroup of a large prime p is vulnerable to certain
attacks known as 'small-subgroup' attacks. Methods exist, however, to
prevent these attacks. This document will describe the situations
relevent to the S/MIME standard in which protection is required and the
methods that can be used to to prevent these attacks.
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