Outgoing SMTP Servers

Dennis Burgess dmburgess at linktechs.net
Tue Oct 25 04:29:05 UTC 2011

I am curious about what network operators are doing with outbound SMTP
traffic.  In the past few weeks we have ran into over 10 providers,
mostly local providers, which block outbound SMTP and require the users
to go THOUGH their mail servers even though those servers are not
responsible for the domains in question!  I know other mail servers are
blocking non-reversible mail, however, is this common?  And more
importantly, is this an acceptable practice?


Most of our smaller ISPs that we support; we allow any outbound SMTP
connection, however we do watch residential users for 5+ outbound SMTP
connections at the same time.  But if the ISP has their own mail
servers, and users wish to relay though them, we basically tell them to
use their mail server that they contract with.  What is the best



Dennis Burgess, Mikrotik Certified Trainer 
Link Technologies, Inc -- Mikrotik & WISP Support Services
Office: 314-735-0270 <tel:314-735-0270>  Website:
http://www.linktechs.net <http://www.linktechs.net/> 
LIVE On-Line Mikrotik Training <http://www.onlinemikrotiktraining.com/>
- Author of "Learn RouterOS" <http://routerosbook.com/> 


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