Re: [EAI] The value of simplified downgrade

[Shawn Steele <Shawn.Steele at microsoft.com>]

John Wrote...

> (ii) The ASCII user does not have an ASCII address for  the
> intended recipient.   In this case, no downgrading mechanism
> that we could devise is going to be helpful -- the situation is
> hopeless and no message can be sent.

That's not quite true.  IF the user has an EAI aware client, it is possible that the message could be downgraded through an algorithmic method, if one was standardized.  So there's two types of ASCII users:

a) if the ASCII user is an ASCII user because they have an ASCII SMTP server, then there's a possible solution.
b) if they're an ASCII user because they can't type Chinese or whatever, then the situation is hopeless, although in the mass-mailing reply-to an EAI aware client could still do an algorithmic downgrade.

>  If I were
> constructing an EAI-aware MUA with multiple identity support,
> I'd want to arrange it to support paired identities and to
> switch to the ASCII address if any or all of the outgoing
> addresses were ASCII.

Do any of the docs make these kinds of implimentation hints?  I think a few things have been mentioned on the list (aliasing techniques / pairing too), that may be useful and not-quite-obvious to implimenters.

> Actually, no.  The user must not only be able to mix those
> addresses, but must also have alternate addresses for all of the
> EAI ones.

This is another case where an algorithmic technique would be helpful.

Note that I don't think that an algorithmic address should be a preferred ASCII address, such as for a business card, but I do think that there is a place for algorithmic addresses as a last-resort downgrade address.

- Shawn