Outbound Port 25 Blocking
What is the Submission Port?
Until now the sending of email has been done through TCP port 25, however it is possible to make the Submission Port (port 587) capable of being used for the sending of email.
With the implementation of Outbound Port 25 Blocking by Asahi Net, those members who have until now been using port 25 when sending their email through another company's outgoing mail server will no longer be able to do so. However, should that company permit use of Submission Port 587, members who change the settings of their email software to use Submission Port 587 should find sending of their email is possible.