Port 25
 

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

Re: Port 25
 

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

Re: Port 25
 

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

Lee

Re: Port 25
 

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?

Re: Port 25
 

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

Re: Port 25
 

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?

Re: Port 25
 

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