On Thu, 27 Feb 2003, Theodore Ts'o wrote: > On Wed, Feb 26, 2003 at 07:49:15PM -0800, ietf1@ka9q.net wrote: > > Other widely deployed but similarly misguided anti-spam mechanisms > > include blanket blocks on incoming or outgoing TCP connections to port > > 25. I've even encountered on ISP that transparently and silently > > redirected my outbound SMTP connections to their own mail servers! > > Yup, some 802.11 wireless "hotspot" networks block port 25 as well. Very > annoying. My personal workaround to this is to have a personal server > tucked away at a colo facility, which among other things, runs a SMTP > server listening on port 2025 (to get around the port 25 blocking > insanity). This SMTP server will relay e-mail on my behalf, no matter > when I am in the Internet, after my laptop uses STARTTLS and AUTH to > authenticate myself to my SMTP server. Many sites, including my university, support STARTTLS+AUTH on the Submission port (587, RFC 2476), which I believe is the recommended service for clients to use to submit mail in any case (though not well-supported among MUAs, to my knowledge), and also is effective at getting around ISP blockage of port 25. Of course if it becomes very popular the misguided ISPs will block it too. - RL "Bob"