This software is a message transfer agent made of five or more processes, with four of them featuring multi-threading. It follows a modularized approach.
The main control program, mcp, bears resemblance to inetd(8) and runs as root in order to bind to port 25 and change the uid of the processes it starts. The other four modules include smtps, smtpc, smar, and qmgr. smtps is an SMTP server that receives emails, while smtpc is an SMTP client that sends emails. smar is an address resolver that provides lookups in various maps, including DNS for mail routing. qmgr is a queue manager that controls the flow of emails through the SMTP servers and clients.
All modules of MeTA1 are designed with the utmost attention to performance, scalability, and reliability. smtps and smtpc utilize the statethreads library, which provides a dependable threading API well suited for Internet applications. On the other hand, smar and qmgr use the POSIX threads API.
The MeTA1 configuration file follows a simple and intuitive format, similar to C programs or BIND 9 configuration files. It does not require any particular layout, such as tabs or one option per line, but instead relies on braces and semicolons as structuring elements.
The first release of MeTA1 is ideal for secure and efficient mail gateways. Its unique features offer advantages not found in sendmail 8 or other open source MTAs. However, while it does not provide built-in support for mail content modification, such as masquerading of addresses or modifying headers, such options can be enabled through the pmilter API. Overall, MeTA1 is an excellent software package with a robust infrastructure that promises to meet the needs of even the most demanding email environment.
Version 1.0.PreAlpha30.0: N/A