email guide

• dmarc (domain based message authentication reporting and conformance)

- Protects domain from unauthorized use. DMARC allows a sender to indicate that their messages are protected by SPF and/or DKIM, and tells a receiver what to do if neither of those authentication methods passes – such as junk or reject the message

• dkim

- digital signature to let the receiver of an email know that the message was sent and authorized by the owner of a domain

• rDNS (reverse)

- Link a server's IP to a domain name
- DNS settings are set with registrars, while rDNS is set with your server or VPS

• rspamd

- advanced spam filtering system and email processing framework. allows evaluation of messages by a number of rules including regular expressions, statistical analysis and custom services such as URL black lists

• spoof

- technique used in spam and phishing attacks to trick users into thinking a message came from a person or entity they know or trust

• SPF

- email authentication standard to prevent spammers sending messages hat appear to come from a spoofed domain

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