ISPs and Port 25



  • I was having trouble sending email back in December - turns out that my ISP decided to start blocking outbound port 25 (SMTP).  I decided to phone them to inquire how, exactly, I was supposed to send email.  After waiting on hold for about 2 hours, listening to "modern christmas carols", I was connected with a rep whose accent was so strong that I almost couldn't tell what he was saying (I'm sure this was intentional).  After being straightforward failed ("You are blocking port 25.  Please cancel this restriction for my account, if possible"), and being subtle also failed ("SMTP isn't working"), I tried the whiny-user approach ("My email isn't working").  The rep then helpfully informed me that they had decided a few days ago that, from now on, all outbound email must be sent through their SMTP server, which happened to be (I'm guessing) an old PI/133 with about 7.3mb of ram, and a 14.4 modem connection.  I tried using thier server for a few days, but after 50% of my email was outright lost, and the rest took about 8 hours to deliver, I gave up and found another (more complicated) solution.

    My question is: How common is this blocking of Outbound Port 25?  Is there anything I can do about it?  I'm in Alberta (Canada), and using an ISP whose name sounds like "Tell us" (which is one of only 2 ISPs up here, the other of which offers 50% slower internet for 50% more price and 50% more downtime).  And they aren't exactly a small ISP either - they're Canada's second-largest carrier, with over 1 million internet customers.  How do they get away with this sort of thing?

     

    PS They also block Inbound Port 80, but that's another story.



  • Nearly universal for consumer-grade internet connections.  For what it's worth, sending through the ISP's mailserver is closer to the Right Thing than you think, but Telus' SMTP server are spectacularly broken in a bunch of ways.  For a while you could only send email that had an @telus.net address in the From: line.



  • Is there anything I can do about it?

    Submit mail via port 576 (rfc2476 mail submission protocol) to an authenticating mail server. People who attempt to force you to use their own mail servers are generally too ignorant to know about it and block it.
     



  • blocking outbound 25 is stupid and I seriously doubt that it's standard for consumer internet.  The reason they get away with it is lack of competition is my guess (you say there are only 2 carriers).  blocking inbound 80 on the otherhand is quite normal...  After all, they wouldn't want you to be able to host a website without paying them more money!



  • @Albatross said:

    My question is: How common is this blocking of Outbound Port 25?  Is there anything I can do about it?

    You could either drop a logic bomb through their back door, or you could use hotmail.

    How do they get away with this sort of thing?

    It's just another example of the Sad Age We Live In



  • Ironically, I am actually hosting a website over this internet connection right now.  It turns out that my email provider supported using port 8025 as an alternate SMTP port, so I'm not using Telus' server any more.  My internet hosting company (No-Ip) provides a service by which they will redirect traffic to my TLD to one of their servers, which serves a frameset pointing to my IP at port 8080.  So I'm hosting a website, and sending email, and there's nothing Telus can do to stop me.  I hope.

    Anyway, thanks for all of the feedback.  Maybe one day we can overthrow the ISPs and get reasonable services.



  • Woh!  Maybe that's why my ssh doesn't work through port 443.  I use the other internet provider in Alberta, and my work blocks port 22 outbound (hence using 443 instead).  Maybe I'll try ICQ port or something that I know I can get out on.



  • @Albatross said:

     And they aren't exactly a small ISP either - they're Canada's second-largest carrier, with over 1 million internet customers.  How do they get away with this sort of thing?

    PS They also block Inbound Port 80, but that's another story.

    They're blocking email spammers. probably a government regulation. you know how a good idea - "let's stop spammers!" turns into "YOU CAN'T EVEN BREATHE ON THE INTERNET, END-USER! MWAHAHAHAHA!"

    :-(

    PS. they're too lazy to do log traces if you were spamming before, this way they just took it out at the source.



  • A friend of mine hosts a couple of small websites on a server in his dining room, on port 80 on domestic broadband.  I also hosted it for a while on my PC when his ISP mucked up his static IP address, also on port 80 on a standard broadband.  Okay performance is awful becuase of the small upstream bandwidth.  He even asked his ISP before getting a static address and they didn't have any problems.

    It had never occured to me that ISP's would block ports.  I pay for an internet connection, they tell me what bandwidth I have and what usage limit (if any) I have, other than that I expect to be able to do what I like. (Within the law, of course)  If I found an ISP blocking ports then I would switch to one that didn't.  I do see that this might be an issue if there are only 2 ISPs in your area though.  Have you considered moving to the UK? :)



  • All ISP's have been doing this here in Ireland since the dawn of the World Wide Web, well, up until a few years ago. The majority seemed to have stopped (with the exclusion of business customers when it comes to some ISP's). Initially this was to force their customers to purchase e-mail accounts from the ISP's rather than purchasing from some other company (yes, this was back in the day when no email accounts were free, or was very difficult to find one that was free and worth it). However come along yahoo mail and hotmail things started to change, people started realising they didn't have to fork out for emails accounts anymore and ISP's stopped blocking port 25. Currently for business customers unless you specifically ask for it, some companies still automatically block port 25, I do believe this is to prevent email spammers (as was pointed out in a post above).


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