Spamd

In this article we will explore in depth the topic of Spamd, its impact on today's society and its relevance in different areas. Throughout history, Spamd has been a topic of great interest and research, with multiple perspectives and approaches that have contributed to the understanding and development of new ideas. From its influence on the economy, culture and politics, to its impact on people's daily lives, Spamd has proven to be a multidimensional issue that deserves to be analyzed and discussed. Through exhaustive analysis, this article will seek to provide a clear and comprehensive view on Spamd, offering readers a deeper and more meaningful understanding of its importance today.

spamd is an ISC-licensed lightweight spam-deferral daemon written under the umbrella of the OpenBSD project. spamd works directly with SMTP connections, and supports features such as greylisting, minimising false positives compared to a system that does full-body analysis. spamd is designed to work in conjunction with pf(4), and should be fully functional on any POSIX system where pf is available, i.e. OpenBSD, NetBSD, FreeBSD and DragonFly BSD.

Uses and features

Spamd is most useful in preventing inbound spam from reaching mail servers. It can also be used as a partial application level proxy to ensure that external mail servers connecting to internal mail servers behave legitimately. Additionally, spamd can be very useful in preventing outgoing spam from systems that may be compromised or under the control of spammers.

It can be used to block spammers with the use of the following features:

  • Blacklisting: such as the SPEWS database or other lists of IPs, and features including small windows sizes.
  • Tarpitting: this can slow down spam reception considerably and hold connections open for a significant amount of time.
  • Greylisting: this forces email to be delayed for a configurable period, requiring the remote end to resend mail at least once in order for it to be delivered.
  • SpamTrapping / GreyTrapping: this is the seeding of an email address so that spammers can find it, but normal users can not. If the email address is used then the sender must be a spammer and they are black listed.

See also

External links