Re: Operations requirement: no hop-by-hop

On 15-feb-04, at 20:04, Paul Hoffman / IMC wrote:

>> To me, this reads as though you want every mail transport session to 
>> live in its own universe without regard to what's happening 
>> elsewhere.

> Correct.

Why??

>> What we need is a way to get the sender to behave according to the 
>> recipients wishes, which makes it necessary to add more feedback to 
>> the new protocol, even if this spans across servers and sessions.

> Then we disagree about requirements here. I think others have said it 
> well: if a sender wants to ignore a recipient's desires, the sender 
> will do so regardless of the protocol.

In that case we don't have a problem as the recipient or an 
intermediate system can terminate the session or throw away the 
message.

What we desperately need is a mechanism that makes it possible for the 
sender and the recipient to interact in a sane and automatic way. 
Bounce messages are hideous, something like this needs to be handled 
automatically rather than be exposed to the user.

> The operational requirement is simplicity and predictability for 
> operators.

I'm sure that's a requirement for operators, but only if we can 
fullfill the requirements of the users as well.

> Adding overhead that pretends that aggressive senders will follow 
> recipient's desires has proven to be a bad design choice for almost 
> ten years now.

That's because they have a choice today: they can ignore the 
recipient's wishes and the message is delivered. That's plain stupid.

> BTW, I'm not against having a way for a good sender to request 
> permission from a recipient: in fact, that is a fine requirement. But 
> that can be done in a different control plane than message 
> transmission.

I don't want to have messages transmitted to me that I know I don't 
want to see. Especially when they're big.