Definition
Anti-spam is any technique, hardware, software, or method adopted to safeguard against spam the widespread distribution of unsolicited messages. Most anti-spam measures focus on emails, as they are the most common method of sending spam.
They identify and remove unwanted items such as generic sales letters and phishing emails, maintaining users’ inboxes clutter-free.
Examples of Real Anti-spam
- Response challenge systems: Requires transmitters to carry out a task for the message to be sent. These are simple tasks, such as completing ‘CAPTCHA’, which automated spam systems cannot do.
- URL filtering: Spam messages often include embedded URLs that redirect users to access websites or launch platforms. Anti-spam software can examine whether these URLs have been blacklisted in publicly accessible domain databases. The one discovered on the list is flagged as spam and rejected.
- DNS blocklists: The DNS disallow list compiles IP addresses of known spam. Email servers check at least one list for the sender’s IP address and spontaneously discard it if it’s from a known spammer.