John W. Moore III johnmoore3rd at
Sat Jun 17 17:57:23 CEST 2006

Hash: SHA512

Jørgen Lysdal wrote:
> If i understand the correctly..
> The "--personal-cipher-preferences" does only have an effect when
> encrypting to more than one recipient, (besides from symmetrical
> encryption algo selection)
> and
> the "--personal-digest-preferences" only when encrypting and signing
> to more than one recipient. Im i right?
> What does it mean to "factor in their own preferred algorithms when
> algorithms are chosen via recipient key preferences."
> Does it mean that, when i encrypt to a key that has, lets say AES
> TWOFISH, and i use --personal-cipher-preferences TWOFISH AES, is the
> message TWOFISH encryptet andgb

Well, Yes & No.  Your personal-preferences are just that.  These are the
ciphers & digests you prefer using.  When Encrypting to *one* other Key
or Many, GnuPG will compare Your preferences to the ones the
recipient(s) have indicated on their Key are theirs.  GnuPG will then
accommodate  all Recipient(s).

In your example the message would be Encrypted using Twofish.  This is
because you are doing the Encrypting and this is what You *prefer* and
the recipient has shown that s/he can handle Twofish.  Should they click
'Reply' and email you back, it would be Encrypted using AES since they
are originating the Encryption and that's their preference and you have
indicated you find AES acceptable.  In the case of multiple
recipients/Keys, GnuPG will determine the common denominator.  This is
why in large Group Encryption environments you will most likely see SHA1
used as the Hash.  It's "common" to every engine.  In encryption you
will generally find 3DES used as the cipher for the same reason.

Timestamp: Saturday 17 Jun 2006, 11:56  --400 (Eastern Daylight Time)
Version: GnuPG v1.4.4-svn4159: (MingW32)
Comment: Public Key at:
Comment: Gossamer Spider Web of Trust (US26):
Comment: Homepage:
Comment: Using GnuPG with Mozilla -


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