Customer-facing ACLs

Christopher Morrow morrowc.lists at gmail.com
Tue Mar 11 02:33:06 UTC 2008


On Mon, Mar 10, 2008 at 7:58 PM, Ang Kah Yik <mailinglist at bangky.net> wrote:
>
>  Hi Justin (and all others on-list)
>
>  I understand your grounds for blocking outbound SMTP for your customers
>  (especially those on dynamic IP connections).
>  It probably will do good to block infected customers that are spewing
>  spam all over the world.
>
>  However, considering the number of mobile workers out there who send
>  email via their laptops to corporate SMTP servers, won't blocking
>  outbound SMTP affect them?
>

vpns fix this...

>  Since these corporate types (I'm guessing here) are probably unaware of
>  how to change their email client's SMTP configurations, chances are that
>  blocking outbound SMTP will probably cause quite a lot of pain.
>

uunet dialup has blocked port25 in both directions since 2002...
little to no complaints. (well, they may have received complaints
since I left, but... thank John StClair for the work behind that
filtering actually.)

>  After all, there are also those who frequently move from place to place
>  so they're going to have to keep changing SMTP servers every time they
>  go to a new place that's on a different ISP.
>

many config's actually just use WCCP to transparently redirect your
smtp to an authorized SMTP server as Andy Dills points out.

-Chris



More information about the NANOG mailing list