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At what level do ISPs control ports?


I'm aware most ISPs do not allow for port 25 to be open for email use outside of business licenses, but at what level is that controlled? Can I get around that by owning my own router? Owning my own modem or ONT? Or is this just a thing they mystically control further up the pipeline that a relative layman such as myself can't get around?
in reply to KasanMoor

You can use a port reflector service. No ip.com might still offer it. Basically forwards anything incoming to their ip on port 25 to your ip and whatever port you specify.
in reply to Brkdncr

@Brkdncr @KasanMoor I don't think they care about incoming port 25, the blocking being talked about is outgoing 25.
in reply to Shiri Bailem

I just looked they have a service called “alternative port 25” that addresses this issue.

Honestly though, once you start adding up costs for these workarounds you have to wonder if it’s easier to just get a business internet circuit, cloud security gateway, or just host the email online.

in reply to Shiri Bailem

@Brkdncr @KasanMoor for reference, mailgun offers a free tier for <5k emails a month. It's what I use for email from any of my servers.

mailgun.com/products/send/smtp…

in reply to KasanMoor

It's all on their end, though I've had limited success asking nicely, it's just there so businesses don't just order the cheaper plan and then they have to deal with all the extra traffic and support for many users. Just assuring them that I am just running as a single user my own email server they were cool with it on small local ISPs bigger corps won't give you the time of day on that issue.
This entry was edited (1 year ago)