RE: SHA 1 vs. SHA 256 for Root CA

["Santosh Chokhani" <chokhani@xxxxxxxxxxxx>]

I do not see a problem with using SHA-1 for a self-signed certificate.
A self-signed certificate is vulnerable to modification and substitution
and hence must be protected using other means while stored or
communicated.

Thus, SHA-1 for self-signed root is fine.  SHA-256 will not protect it
any better.

You can not say the same about the certificates issued by the Root. 

-----Original Message-----
From: owner-ietf-pkix@xxxxxxxxxxxx [mailto:owner-ietf-pkix@xxxxxxxxxxxx]
On Behalf Of ROGER YOUNGLOVE
Sent: Monday, January 29, 2007 9:39 AM
To: ietf-pkix@xxxxxxx
Subject: SHA 1 vs. SHA 256 for Root CA


We are standing up a number of CAs (Selfsigned Root, Policy and
Issueing).
The question has come up with the Microsoft CA product we have the
ability 
to chose SHA 1, SHA 256, SHA 512. i believe that SHA1 is not sufficent
for a 
20 year root CA lifespan. I need expert support for moving to SHA 256 at
a 
minimum.

Roger Younglove
Principal Consultant
Ford Motor Company