Comcast and Port 25 Blocking

[bill at horne.net]

I called up Comcast's PR department yesterday, and asked them to 
tell me what the guidelines are for blocking port 25. 

The person I spoke with denied there is any policy to block port 25
inbound (cloud -> end user) but he said they block port 25 going
outbound (user -> cloud) if they suspect spamming or a zombie machine.

He promised to check with the "higher ups" and get back to me.

My access to port 25 started working shortly thereafter.

Conclusion: I think Comcast has some automated system that blocks port 25
based on criteria they don't want to reveal. The guy I talked to said 
any blocking happens at the cable modem, so I don't know if changing the 
MAC address so as to get a different IP would make any difference.

If you're a Comcast subscriber, and port 25 is blocked at your machine, 
please send me an email giving your name and address. I'll prepare 
a case for Comcast to exempt the "Linux" class of machine from the 
blocks.

Bill Horne


--
E. William Horne
William Warren Consulting
Computer and Network Installation and Service
781 784-0951