Lazy network operators

Wed Apr 14 10:19:04 UTC 2004

On 14-apr-04, at 11:50, Petri Helenius wrote:

>> I wonder how this is going to affect SMTP mail handling as
>> it stands - for example, how many 'hops' will there be
>> between this university's mail gateway and, say, MIT's
>> mail gateway(s)? Will people start playing header rewrite
>> tricks so MTAs around the world don't bomb out with
>> "exceeded hop count" ? "Just one hop!" games, a la IP routing in
>> the final stages of last century, may rear its ugly head again.

> Could the MTA´s run something similar to MPLS so they could reduce the 
> hop count and "funnel" the email though instead of storing and 
> forwarding it hop by hop? Maybe some users would then be willing to 
> pay more for the extra complexity and it would also skyrocket job 
> security.

How would multi-hop routing work for ~100M domains, anyway?

Requiring a hop in the middle could be useful in order to create a 
choke point where rate limiting can be done, but doing multihop makes 
little sense. The authorization information implied in the routing can 
just as easily be learned from the sender, if protected through 
cryptographic means. (Yes, #include <pki.h> but that's the part where 
we show that we aren't so lazy after all.)