Mailing servers are software which is capable of transferring electronic mail messages from computer to another with the help of a client-server application. The building of the software utilizes some standard protocols, to enable it to transfer both messages and data files.
Simple mail transfer protocol is used mainly because:
- It is capable of coping with discontinuous connections. In the earlier days, inter-network connections were not available; hence readers were not in need of access protocol. Readers had a direct way of accessing their mailbox, with the use of the terminal connection. However, if an SMTP is configured to utilize backup MXes, it can withstand temporary local network outages.
- Submission policies. Systems are presently built to enable users to send messages to local servers for policy reasons and not technical reasons.
Although mailing servers are a useful tool in any business, small businesses, and homeowners interested in running, their mailing servers are facing challenges, because centralization and issues concerning spams. As a result, larger mailing servers have continued to increase strict measures, to other mailing servers who want to transfer emails from them.