Steve
I'm a PC, so shut up
Consultant
join:2001-03-10
Yorba Linda, CA
| How hard could this be?
Many other cable providers have managed to block port 25/tcp - why is it so hard for Comcast? I think they are still regionalized, so some areas may not have the equipment to handle it, but when it looks like they're doing nothing but saying "Yah, we suck", others are inclined to agree with them.
I have been blocking the entire Comcast IP range for months.
Steve
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Stephen J. Friedl * Security Consultant * Tustin, California USA * my web site |
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pnh102
Reptiles Are Cuddly And Pretty
Premium
join:2002-05-02
Mount Airy, MD
 ·Comcast
| said by Steve  :
Many other cable providers have managed to block port 25/tcp
There are many legitimate email users who send outbound email via Port 25 using their own hosted email services. If they block Port 25, the spammers will simply use another port.
There are other ways to track and disable infected PCs, Comcast should use those instead.
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Keep America Strong! Bush/Cheney 2004 |
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kpatz
MY HEAD A SPLODE
Premium
join:2003-06-13
Manchester, NH
2 edits | reply to Steve
The article addresses this - blocking port 25 would create a tech support nightmare with the possibly thousands of support calls from people who use smtp servers other than Comcast's, and would cost them a lot of money in support costs. Instead, according to the article they will monitor traffic and block the port only for subscribers who are sending out large volumes of email.
IMHO, this is a better solution than blocking the port for everyone. Just punish the bad folks, and leave those who behave alone.
It isn't that they have a large percentage of zombied users out there, it's actually quite a small percentage. The reason they are the "worst spammers" is simply because they are the largest ISP. A small percentage of a large number is still a large number. Blocking 25 would adversely affect a far larger percentage of subscribers than those who are spammers or zombie hosts.
So when you see that more spam is coming from Comcast IPs than, say, Verizon IPs, remember that Comcast has far more subscribers.
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Robert Tappan Morris, Jr., got six months in jail for crashing 10% of the computers that Bill Gates made $100 million crashing last weekend. |
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gaforces
United We Stand, Divided We Fall
join:2002-04-07
Santa Cruz, CA | reply to Steve
at least they acknowledge the problem  |
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Steve
I'm a PC, so shut up
Consultant
join:2001-03-10
Yorba Linda, CA
| reply to pnh102
said by pnh102 :
If they block Port 25, the spammers will simply use another port.
Huh? My mailserver only listens for traffic on port 25/tcp, so if spammer try to use another port, they're not going to get anywhere.
Steve
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Stephen J. Friedl * Security Consultant * Tustin, California USA * my web site |
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Thaler
Premium
join:2004-02-02
Encino, CA
| reply to pnh102
There are many legitimate email users who send outbound email via Port 25 using their own hosted email services. Correct me if I'm wrong, but I thought basic Comcast internet service (along with most other DHCP internet services) prohibits server functions on their basic residential internet package.
If Comcast were to shut down port 25, customers with these service packages that are legitimately affected do not have any grounds with which to complain upon. Therefore, they could just shut down this port for these customers, and should people complain about this service being blocked...well, RTFM...er, user agreement, not manual. ^_^ |
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pnh102
Reptiles Are Cuddly And Pretty
Premium
join:2002-05-02
Mount Airy, MD
·Comcast
| said by Thaler :
Correct me if I'm wrong, but I thought basic Comcast internet service (along with most other DHCP internet services) prohibits server functions on their basic residential internet package.
You're right, but most of us who do these things are not running servers on Comcast connections. Rather, what we are doing is buying our own domain and hosting, and sending email through that host, using that host's port 25. If Comcast were to block outgoing port 25, then email would not work.
Although most hosting companies do provide an alternative port to send email, it is still not fair that users who keep their machines virus-free should have our connections hobbled because some idiot is too lazy to maintain their system.
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Keep America Strong! Bush/Cheney 2004 |
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pnh102
Reptiles Are Cuddly And Pretty
Premium
join:2002-05-02
Mount Airy, MD
·Comcast
| reply to Steve
said by Steve :
Huh? My mailserver only listens for traffic on port 25/tcp, so if spammer try to use another port, they're not going to get anywhere.
Sorry, I was not clear in my parent post. I was referring to Comcast's blocking outbound port 25 so that I could not reach my domain's hosted email server.
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Keep America Strong! Bush/Cheney 2004 |
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nixen
Rockin' the Boxen
Premium
join:2002-10-04
Alexandria, VA
·Cox HSI
 ·Speakeasy
| reply to pnh102
said by pnh102 :
said by Thaler :
Correct me if I'm wrong, but I thought basic Comcast internet service (along with most other DHCP internet services) prohibits server functions on their basic residential internet package.
You're right, but most of us who do these things are not running servers on Comcast connections. Rather, what we are doing is buying our own domain and hosting, and sending email through that host, using that host's port 25. If Comcast were to block outgoing port 25, then email would not work.
Although most hosting companies do provide an alternative port to send email, it is still not fair that users who keep their machines virus-free should have our connections hobbled because some idiot is too lazy to maintain their system.
You're rather contradicting yourself here. First you say that SMTP relay services are available through other ports, then you say that blocking port 25 hobbles your service. Which is it?
I'm sorry, but port 25 is for MTA to MTA SMTP traffic. SMTP submissions via SMTP clients should be done via authenticated connections to the MSA at port 587.
-tom
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"There are 10 types of people in the world... those who understand binary and those who don't."
"That's only 2 types of people, moron" |
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Rhobite
Premium
join:2002-02-24
Cambridge, MA
clubs:
| reply to Thaler
We're talking about shutting down outgoing port 25, not ingoing. This has nothing to do with a customer running a server on their Comcast line. Port 25 blocks do affect legitimate users, but given the damage done by spammers I think an ISP is within its rights to block outgoing 25.
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Jimmysquid.com - I take pictures. |
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