QMQP: That Other Mail Transfer Protocol

Everyone (okay, everyone this is relevant to) knows what SMTP is, the standard for mail transfer. It’s even in the name, Simple Mail Transfer Protocol, which is how mail servers have been sending mail to other mail servers since… a while. Well, fun fact, there’s another protocol that accomplishes the same goal: QMQP, the Quick Mail Queuing Protocol.

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How DNSBLs Work

Ff you’ve dealt with email for any longer than 5 minutes (as an administrator), you already know it’s a mess. There’s so many security measures, so many checks, so many things to combat bad actors and spam. What if we had some way to have some service publish a list of bad DPs, and mail servers could quickly check that mid-transaction so they can have up-to-date information as to if the in-flight message should actually be accepted or not?

Well, we have exactly that. Enter: the DNS Blacklist.

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