Signature sizes (was: DSA 1024-bit limit)

Daniel Carrera dcarrera@math.umd.edu
Thu May 15 01:17:02 2003


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That's not quite what I wanted to know, but you pointed me in the right=20
direction.  Thanks.

I just compared a DSA and an RSA signature.  I don't see the what the=20
problem with RSA signatures is.  It doesn't look that big to me.  For a=20
sample text the DSA signature is 3 lines and the RSA is 7 lines (see=20
further below).

Is the signature size the main drawback of RSA signing?

Also, another queston:
Do RSA signatures use the same hash as DSA?
Does the hash limit the security of RSA signatures?

Thanks for the help,

DSA:
iD8DBQE+wsuNngS5oA/rzsMRAgRVAJ0dcNxcKoxfwfnnZsDfESQgsarSVACeIjN6
Dw+Z/HLTRe2ECQWl95j1Ms0=3D
=3DpP/2

RSA:
iQEVAwUBPsLLxpMuikfjyo+uAQIc5QgAlNbSVTNZEQkXrbUXsqj7Z9USa7aCU5eW
e7k8qfQzGINmr1RICapqkj/rzoO8Jdm0hXvZS2YBcNg3YZ/AZqiQorVrBE8cfme7
ZKNjOjZBSmL26E/8rVk2jmiMt+ZhkOa3kaITn6K+HekK18NHluyTv+IZpj8CaVEm
Ep+pKNQHRRTkZFRYccqUorsgte/ZEbLF1tlO/gIWnGi/9v98531CyAMT3iM2O3n0
a1MngZcGuVb+I50nm4QWGOu8BhfgT8MXZThiJiHuDYObJgFqW4sP04rmIx5cG270
i9OcgacTrgRUrFA59oxXYRuhAVs7JTIPvUfXbQBhJtgosxVAHHDDfw=3D=3D
=3D3qYV




On Thu, May 15, 2003 at 12:15:03AM +0200, Manuel Samper wrote:
> Daniel Carrera, on Wednesday, May 14 2003 at 23:25, wrote:
> > I'm still hoping to learn how I can use two different signing keys.
> > Once I have my two keys, how can I switch from signing with one to the=
=20
> > other.
>=20
> That depends on the software which calls gpg, i.e., if you want to sign
> emails, and you use mutt, select "sign (a)s" in the compose menu. You
> may want to set a "pgp_sign_as=3D<your_signing_keyid>" and to replace the
> default "pgp_(encrypt_)sign_command" settings (adding a exclamation in
> "%?a?-u %a!?"), but this is a mutt/whatever MUA/software issue, of
> course.
>=20
> --=20
> Manuel Samper
> PGP/GPG KeyID: FFFD5DA0
>=20
> _______________________________________________
> Gnupg-users mailing list
> Gnupg-users@gnupg.org
> http://lists.gnupg.org/mailman/listinfo/gnupg-users

--=20
Daniel Carrera         | OpenPGP fingerprint:
Graduate TA, Math Dept | C678 4F28 6418 6A62 F186 98FC 9E04 B9A0 0FEB CEC3
UMD  (301) 405-5137    | http://www.math.umd.edu/~dcarrera/pgp/key.html

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B7hYHfa5MzjNq1aMoJNi4vB4qfk2ZPbOqJ6NQk5ycWAqJ6bVLhAU+Q==
=l4ue
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