The relaying of Junk/Spam email is caused by disreputable people using other people's mail systems to send their unsolicited advertising thereby ensuring that the relaying system is blamed for the email rather than the original sender.
When a mail server is not correctly installed and secured it can be used to relay junk/spam mail.
Once an open mail relay has been identified by a remote 'hacker' they will then send huge volumes of mail through the server until it either crashes or is shutdown; this has a number of direct effects:
- The abused mail system may be recorded on one or more of the multitude of email blacklists held around the world and so be unable to send email in future to other sites.
The problem with these lists being that it is easy to get on and very hard to get off.
- altohiway mail servers (being the mail relay for the customer in a lot of cases) may also be blacklisted which then affects other customers.
- altohiway servers will also have an unusally high influx of the junk email which will then also produce a massive amount of bounces throughout our network (as a large proportion of the junk mail will be to invalid addresses).
The abused mail system becomes jammed, unstable or possibly crashes and requires substantial amounts of work to bring back online.
Obviously none of the affects above are desirable from anybody's perspective, so we are eager to ensure our email systems are secured when they are installed rather than waiting for one of these incidents to occur.
We provide a free of charge mail system checking utility to check your mail server.
Methods of securing mail systems are specific to the mail system installed; we have provided a number of documents on our website for securing more popular mail systems.
In addition you can also look at the MAPS website which is a valuable source of information on securing all manner of systems.
Useful link: The Maps Website (securing other systems)
