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JohnInSJ
Premium Member
join:2003-09-22
Aptos, CA

JohnInSJ to NormanS

Premium Member

to NormanS

Re: Comcast decides to block port 25 IN and OUT with no notice.

said by NormanS:

said by JohnInSJ:

didn't see the quit, thought he just disconnected - forgive me. Whatever, no port 25 on residential, that's the rule.

Whose rule? And how do you actually determine "residential"? I test for "DUL" on my server; "Dynamic User List".

Comcast's rule, per the post title, is that they will block port 25 on residential accounts.

Am I in the wrong thread?

I frankly don't care at all, I am on business class with static IPs because the features and access I require are available with that service.

NormanS
I gave her time to steal my mind away
MVM
join:2001-02-14
San Jose, CA
TP-Link TD-8616
Asus RT-AC66U B1
Netgear FR114P

NormanS

MVM

said by JohnInSJ:

Comcast's rule, per the post title, is that they will block port 25 on residential accounts.

Am I in the wrong thread?

No, but I was sucked away from the OPs concerns by my own obstinacy.

OP wants to test an off-Comcast network SMTP server, and definitely should get a business-class account for that purpose.

ArrayList
DevOps
Premium Member
join:2005-03-19
Mullica Hill, NJ

ArrayList

Premium Member

said by NormanS:

OP wants to test an off-Comcast network SMTP server, and definitely should get a business-class account for that purpose.

really? a business class connection just to test if port 25 is working?

JohnInSJ
Premium Member
join:2003-09-22
Aptos, CA

JohnInSJ

Premium Member

said by ArrayList:

said by NormanS:

OP wants to test an off-Comcast network SMTP server, and definitely should get a business-class account for that purpose.

really? a business class connection just to test if port 25 is working?

Why does a residential user need to "test if port 25 is working" on a server they don't run?

ArrayList
DevOps
Premium Member
join:2005-03-19
Mullica Hill, NJ

ArrayList

Premium Member

the server is not run on the business class connection. That alone says that you don't need business level service.

JohnInSJ
Premium Member
join:2003-09-22
Aptos, CA

JohnInSJ

Premium Member

said by ArrayList:

the server is not run on the business class connection. That alone says that you don't need business level service.

I have no idea what you're saying here. You aren't allowed to run any server on residential. Only an SMTP SERVER needs to send traffic on port 25. Therefore you need to be on business class to send traffic on port 25. QED

NormanS
I gave her time to steal my mind away
MVM
join:2001-02-14
San Jose, CA
TP-Link TD-8616
Asus RT-AC66U B1
Netgear FR114P

1 edit

NormanS to ArrayList

MVM

to ArrayList
said by ArrayList:

said by NormanS:

OP wants to test an off-Comcast network SMTP server, and definitely should get a business-class account for that purpose.

really? a business class connection just to test if port 25 is working?

Yes, because port 25 is no longer a standard user port; hasn't really been since RFC 2476 was published in December, 1998.

ArrayList
DevOps
Premium Member
join:2005-03-19
Mullica Hill, NJ

ArrayList to JohnInSJ

Premium Member

to JohnInSJ
said by JohnInSJ:

said by ArrayList:

the server is not run on the business class connection. That alone says that you don't need business level service.

I have no idea what you're saying here.

I don't run a server on my connection, why can't I open a tcp connection to a remote server over port 25 without paying more money for the privilege to do so? I really don't care either way. Spammers will spam regardless of what Comcast does.
AVonGauss
Premium Member
join:2007-11-01
Boynton Beach, FL

AVonGauss

Premium Member

Blocking outbound 25/tcp significantly lowers the amount of e-mail spam coming from an ISP. If you run a mail server, it's very easy to tell who is blocking and who is not blocking based on the spam mail attempts.

I probably already said this in this thread, but Comcast should have done this years ago.

graysonf
MVM
join:1999-07-16
Fort Lauderdale, FL

1 recommendation

graysonf to ArrayList

MVM

to ArrayList
Get a free shell account on »www.cjb.net

Connect anywhere you want to destination port TCP 25.

JohnInSJ
Premium Member
join:2003-09-22
Aptos, CA

1 recommendation

JohnInSJ to ArrayList

Premium Member

to ArrayList
said by ArrayList:

said by JohnInSJ:

said by ArrayList:

the server is not run on the business class connection. That alone says that you don't need business level service.

I have no idea what you're saying here.

I don't run a server on my connection, why can't I open a tcp connection to a remote server over port 25 without paying more money for the privilege to do so? I really don't care either way. Spammers will spam regardless of what Comcast does.

Port 25 communications is reserved for servers. That's why.

NormanS
I gave her time to steal my mind away
MVM
join:2001-02-14
San Jose, CA
TP-Link TD-8616
Asus RT-AC66U B1
Netgear FR114P

NormanS to ArrayList

MVM

to ArrayList
said by ArrayList:

Spammers will spam regardless of what Comcast does.

Prior to 2002, when SBC blocked customer access to port 25, SBC residential hosts were the most prevalent spam source IP addresses in my server logs. Subsequent to the blocking, SBC residential hosts dropped to near last. While spammers continued to spam, they were much less successful at using compromised SBC residential customer hosts.

FWIW, SBC led Comcast until the blocks. After the SBC blocks, SBC dropped behind Comcast as a spam source. From which I deduced that blocking port 25 reduced the amount of abuse coming from SBC.