Key Usage Extension Encoding

[Trevor Freeman <trevorf@xxxxxxxxxxxxx>]

I am canvassing opinion on how the key usage field should be encoded.  I
have heard some divergence of opinion which seems to be rooted in
differing interpretations of the ASN encoding rules as well as the
actual pkix usage.  ASN rules state any unused bits are set to zero.
There are now 9 bits defined in the key usage extension in pkix part 1
v5. If I wanted to set digital signatures and key agreement (bit 0 and
bit 4), what would the encoded bit string look like and how many bits
are encoded to be in use 2 or 9?
Thanks
Dr Trevor Freeman
Senior Consultant
Microsoft Consulting Services
Microsoft Ltd ECU
> Tel:  UK(+44) 1734 270412 
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