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Re: Broadcasts - addressing
> I have been contemplating how to mark broadcast messages as being
> 'for' someone. To foil traffic analysis, you don't want to include
> their nym or key-id, for the sake of the your poor CPU, you want to
> avoid the need to attempt decryption on everything that passes through.
The main problem is how to avoid decrypting _most_ of the traffic,
without giving away significant information about the recipient.
One approach is to do something some political users have been asking for -
implement support for very short keyids (e.g. 4 bits instead of 24-32),
so that the keyid isn't a good identifier for the user.
Another approach is to include a tag in the Subject: with either a hash
of the key (substantially reducing the number of bits),
or simply the last hex or two of the keyid - that lets you ignore
15/16th or 255/256th of the traffic, without giving away much.