Transparent hijacking of SMTP submission...

William Herrin bill at
Sat Nov 29 15:44:35 UTC 2014

On Thu, Nov 27, 2014 at 9:51 PM, Jay Ashworth <jra at> wrote:

> ----- Original Message -----
> > From: "William Herrin" <bill at>
> > I'm not sure I follow your complaint here. Are you saying that Comcast
> > or a
> > Comcast customer in Washington state stripped the STARTTLS verb from
> > the
> > IPv4 port 587 SMTP submission connection between you and a third
> > party?
> Yup; that's what he's saying.  This was in the technical press earlier this
> week -- or the end of last.

Hi Jay,

Seems to me that if an ISP is altering the contents of its users' packets
(not just blocking them, altering them) then that ISP should be named and
shamed, if not worse. Unless the customer contracted for special account
type where that was a desired and intended feature, such behavior is

If it's a customer of that ISP, on the other hand, then it's just the
normal idiocy and paranoia, no different than the retarded behavior by
amateur sysadmins that block all ICMP because they don't want to be pinged
(see PMTUD and its effects on TCP).

Anyway, I was curious which accusation was being leveled.

Bill Herrin

William Herrin ................ herrin at  bill at
Owner, Dirtside Systems ......... Web: <>
May I solve your unusual networking challenges?

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