nanog mailing list archives
Re: Why do so few mail providers support Port 587?
From: Valdis.Kletnieks () vt edu
Date: Mon, 28 Feb 2005 17:13:35 -0500
On Mon, 28 Feb 2005 16:54:23 EST, Nils Ketelsen said:
An interesting theory. What is the substantial difference? For me the security implications of "allowing the user to bypass our mailsystem on port 25" and ""allowing the user to bypass our mailsystem on port 587" are not as obvious as they maybe are to you.
The big difference is that if they connect on outbound 25, they're basically unauthenticated at the other end. Port 587 "should be" authenticated, which means that the machine making the connection out is presumably a legitimate user of the destination mail server. If you're managing a corporate network, then yes, the distinction isn't that obvious, as you're restricting your own users. If you're running an ISP, you're being paid to *connect* people to other places, and making it more difficult than necessary is.. well... a Randy Bush quote. ;)
Attachment:
_bin
Description:
Current thread:
- Re: Why do so few mail providers support Port 587? Michael . Dillon (Feb 28)
- <Possible follow-ups>
- RE: Why do so few mail providers support Port 587? Michael . Dillon (Feb 28)
- Re: Why do so few mail providers support Port 587? Steven M. Bellovin (Feb 28)
- Re: Why do so few mail providers support Port 587? Nils Ketelsen (Feb 28)
- Re: Why do so few mail providers support Port 587? Valdis . Kletnieks (Feb 28)
- Re: Why do so few mail providers support Port 587? Nils Ketelsen (Mar 01)
- Re: Why do so few mail providers support Port 587? Frank Louwers (Mar 01)
- Re: Why do so few mail providers support Port 587? Nils Ketelsen (Mar 01)
- Re: Why do so few mail providers support Port 587? Valdis . Kletnieks (Mar 01)
- Re: Why do so few mail providers support Port 587? Valdis . Kletnieks (Feb 28)
- Re: Why do so few mail providers support Port 587? Valdis . Kletnieks (Mar 01)
- Re: Why do so few mail providers support Port 587? Michael G (Mar 01)
- Re: Why do so few mail providers support Port 587? Jason Frisvold (Mar 01)
- Re: Why do so few mail providers support Port 587? David Lesher (Mar 01)
- Re: Why do so few mail providers support Port 587? Chris Horry (Mar 01)
- Re: Why do so few mail providers support Port 587? Stephen Fulton (Mar 01)