What is DKIM?
DomainKeys Identified Mail (DKIM) is an email authentication protocol that helps combat email spoofing. It works by digitally signing outgoing emails with a cryptographic key associated with the sender’s domain. This signature allows receiving mail servers to verify the legitimacy of the sender’s domain and ensure the message hasn’t been tampered with in transit.
Use Cases of DKIM_
- Prevent email spoofing: DKIM helps prevent attackers from forging a sender’s email address to impersonate a legitimate sender (e.g., a company or individual).
- Improve email deliverability: By implementing DKIM, organisations can increase the chances of legitimate emails reaching recipient inboxes and avoid spam filters.
- Enhance email trust: DKIM validates the sender’s domain, building trust with recipients and reducing the risk of phishing attacks.
Key Components_
- Signing key pair: A cryptographic key pair consisting of a private key (kept secure by the sender) and a public key.
- DKIM signature: A digital signature added to the email header using the private key. This signature is based on specific message components like sender address, recipient address, and message body.
- DKIM public key record: The public key published as a TXT record in the sender’s Domain Name System (DNS). Receiving mail servers use this record to verify the DKIM signature.
Microsoft 365 fully supports DKIM. By implementing DKIM with Microsoft 365, organisations can:
- Sign outgoing emails: Microsoft 365 can automatically sign outgoing emails with a DKIM signature using a generated key pair.
- Validate incoming DKIM signatures: Microsoft 365 can verify DKIM signatures on incoming emails, helping to identify potential spoofing attempts.
- Improve email security posture: DKIM, combined with other Microsoft 365 security features, strengthens email protection and increases confidence in legitimate email senders.
By leveraging DKIM with Microsoft 365, organisations can significantly enhance their email security and reduce the risk of falling victim to email spoofing and phishing attacks.
