The Book of PF

Giving Spammers a Hard Time with spamd

One other service that needs some special attention is email. Email is one of the older Internet services and one we would not like to do without. In the form of SMTP and a host of retrieval protocols, email is one of the basic services on any TCP/IP network. So basic, in fact, that it's extremely hard to even imagine what the Internet would be without it.

By the early years of the present century, the commercialized Internet had seen the rise of spam as a problem that threatened to make SMTP email less useful. Various content-filtering solutions were devised, and while a number of the open-source ones ran well on the BSDs, the OpenBSD team set to work on its own spam-fighting solution, dubbed spamd, in early ...