olemus
(1) meiliagent (= mail transfer agent):
rakendusprogramm, mis edastab e-kirju
ühelt arvutilt teisele klient-server-mudeli alusel
= a program that transfers electronic mail messages from one computer to another

(2) virtuaalne postkontor (= mail hub):
arvuti, mis talletab võrgustatud klientide e-kirju
= a host that provides “electronic post office” facilities:
a computer used to store and/or forward electronic mail

ülevaateid
https://en.wikipedia.org/wiki/Message_transfer_agent

http://www.samlogic.net/articles/mail-server.htm

https://wiki.archlinux.org/index.php/Mail_server

https://en.wikipedia.org/wiki/Comparison_of_mail_servers

https://en.wikipedia.org/wiki/List_of_mail_server_software

turvalisus
https://www.vircom.com/blog/top-10-tips-to-secure-your-email-server/

https://www.alienvault.com/blogs/security-essentials/basic-best-practices-for-configuring-email-servers

https://www.apriorit.com/qa-blog/428-mail-server-security-testing

vt ka
- avatud meiliserver
- meilivahendusserver