ingress SMTP

Daniel Senie dts at
Wed Sep 3 16:52:18 CDT 2008

At 12:48 PM 9/3/2008, you wrote:

>>Do you operate your mailserver on a residential cablemodem or adsl
>>rather than a business account?
>No, we co-lo equipment at a professional facility that our customers 
>on any type of connection need to have access to send mail through, 
>regardless of whether their ISP blocks the standard ports or not.
>-Justin Scott, GravityFree

I've been running a similar operation for over a decade, offering 
email services, web services and collocation to businesses from the 
tiny to the multinational. We have, since the beginning, provided 
instructions on using port 587 and port 465 for email submission. 
This is not hard to explain, and it has never been a problem for our 
customers or their tech folks to accomplish.

Our servers are in data centers, our customers are on DSL, cable or 
even dialup circuits. We assume port 25 will be blocked, and while it 
isn't always, starting with that assumption simplifies matters. We 
also encourage our customers to always use TLS or SSL for all 
exchanges with the mail servers.

Because we have many users who are road warriors, they never know who 
their local access ISP will be. Getting them set up for 587 or 465 
before they leave home has always kept folks out of trouble. And 
those few who don't heed our advice have had their email hijacked by 
hotel networks that consume traffic to any remote port 25 themselves 
in an attempt to "help." So again, just get your customers configured 
right at the start, and there will be few support calls on the subject.

This is just part of being a third-party supplier of email services 
in the current reality.


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