Port 25

[numenory]

After some time on the phone to NTL/Virgin Media support I am assured (100%) that the TCP port number 25 is not being block by NTL/Virgin for connections to the consumer.

My own investigations suggest that incoming connections to the consumer on port 25 are being blocked, this is a change that seems to have been made in the last week.

Could anyone shed some light on the matter?


Many Thanks


Lee

[SnoopZ]

Port 25 is the Simple Mail Transfer Protocol (SMTP) for outgoing email so that won't be blocked.

https://www.grc.com/port_25.htm

[numenory]

Unfortunately that is incorrect a port may be blocked on either an inbound or outbound basis

Lee

[Richy99]

if port 25 was blocked then no one would be able to send emails out, but why are you trying to accept incoming conentions on port 25?

[numenory]

Many thanks for anyone who posted in reply to this, I have sorted the problem.

The reason that i want port 25 open for incoming is that I have something listening on the port.

The problem was however a config error of my own making.

For general information on ports and for example web pages / http / webservers generally run on port 80, it would be possible for ntl if they wanted to block access to this port to your house/building. This would not prevent you accessing web pages, it would prevent access from the outside world to your house on port 80 thus preventing you from running a web server in your home.

Many thanks for the replies,

Lee

[brundles]

If you can move the server off that port your should do. As already mentioned, port 25 is the SMTP port. Even though you might not (you don't specify) be running a mail server on that port, if it's identified as open you're asking for trouble.

How would you application cope with a relentless barage of spammers trying to connect thinking there is an SMTP server on it they can use?

[numenory]

brundles many thanks, sorted and it was a mail server hence 25