Spam (Ham)

A spam is an unsolicited mail.

It's also known as:

• Unsolicited Bulk Email (UBE)
• or Unsolicited Commercial Email (UCE)

• Email - Authentication

https://www.greylisting.org/ - Base on the fact that a Spam server will never try to send the email again, the first email received from an unknown sender is rejected and is placed in a grey listing and if the smtp server sends it again after the grace period, the sender is placed on the white list.

spamd has a rejection base on grey listing.

• https://mailspike.org/

• https://spamassassin.apache.org/

A list of IP/mail that should be blocked. Email - Blacklist

Spam may be indirect.

For instance:

• when a comment is posted, an email is send to the subscriber and the administrator receive it.
• or via blog trackback

A spam trap is an email address that’s not actively used, but is actively monitored. If a spam trap receives an email, something is rotten because that email address never opted in to receive emails.

Spam emails use the unsubscribe option to confirm that your email is in fact legit and active.

spamd is a fake mail daemon which rejects false mail.

Email - Score

• Fighting Spam with Reputation Systems