Author: Phil Pennock Date: To: exim-users Subject: Re: [Exim] Failing behviour based on SMTP codes.
On 2000-10-17 at 22:48 +0530, Suresh Ramasubramanian gifted us with: > As most of the large American ISPs have applied port 25 blocking across their
> dhcp pools (where most intermittently connected hosts live), most people would
> smarthost through their own ISP's smtp server, rather than relay through their
> own domain's MTA, which might be remotely hosted (and ideally using some form
> of AUTH for relaying).
If you already have your own MTA, beyond the control of your ISP, then
you can set it up to route to your dial-up box on another port. If the
ISP blocks incoming syn-only packets, then either (a) change ISP; or
(b) use auth-based TURN.
Perhaps I'm paranoid (but then, I'm paid to be paranoid :^) ) but all
these new port-blocks:
* forced web-caching for outgoing HTTP (layer-4 routing)
* forced SMTP-smarthosting for outgoing mail (and using DUL)
* blocking incoming SMTP (as described above)
make it _remarkably_ easy for people interested in snooping on your
behaviour to do so.
If I were an employee of a spook agency (post-brainwashing), I'd be
actively encouraging these sorts of technology developments.
--
Civilisation: where they cut down the trees and name streets after them.