Tehnički odnos između SPF-a, DKIM-a, DMARC-a i BIMI-ja objašnjen jednostavno

• SPF (Sender Policy Framework): Ovaj protokol provjerava je li poslužitelj pošte koji šalje poštu ovlašten za slanje e-poruka za vašu domenu. Koristi DNS zapise kako bi definirao kojim poslužiteljima je dopušteno slanje u vaše ime, što pomaže u blokiranju lažnih pošiljatelja.
• DKIM (DomainKeys Identified Mail): DKIM dodaje digitalni potpis svakoj odlaznoj e-pošti. To omogućuje poslužitelju primatelja da provjeri da e-pošta nije mijenjana i da doista dolazi s vaše domene.
• DMARC (Provjera autentičnosti, izvještavanje i usklađenost poruka temeljena na domeni): DMARC povezuje SPF i DKIM, osiguravajući da se domene koje provjeravaju podudaraju s vidljivom adresom "Od". Također vam omogućuje postavljanje pravila o tome što učiniti s e-porukama koje ne uspiju proći provjeru autentičnosti - staviti ih u karantenu ili ih odbiti - te pruža izvješća o rezultatima provjere autentičnosti.

• BIMI (Brand Indicators for Message Identification): BIMI is the “bonus” that comes after you’ve set up SPF, DKIM, and DMARC correctly. Once your domain passes these checks, BIMI lets you display your brand’s verified logo next to your emails in supported inboxes.
• Technical Requirement: BIMI only works if your DMARC policy is set to “quarantine” or “reject,” not “none.” This ensures only authenticated, trusted emails can display your logo, protecting your brand from spoofing.
• How It Works: You publish a BIMI record in your DNS, pointing to your logo file (and sometimes a Verified Mark Certificate). When an email passes SPF, DKIM, and DMARC, the recipient’s mail server checks for a BIMI record and, if present, displays your logo in the inbox.

• Security: SPF, DKIM, and DMARC work together to block phishing, spoofing, and unauthorized use of your domain.
• Trust: BIMI rewards strong authentication by making your brand instantly recognizable in the inbox, boosting recipient trust and engagement.
• Visibility: Only domains with robust authentication and DMARC enforcement can use BIMI, ensuring that only legitimate brands benefit from enhanced inbox branding.

Think of SPF, DKIM, and DMARC as the security checks at the front door. Only after you’ve passed all three can you hang your brand’s logo (BIMI) proudly in the window for everyone to see.