Alignment
The relationship between an authenticated SPF or DKIM domain and the visible From domain. A passing result must align to count towards DMARC.
Explore this topicThe plain-English glossary
Every acronym.
A little less mysterious.
A quick reference for the words you’ll meet on your BIMI journey.
28 terms, explained simply
Authentication
Technical checks that establish whether a message is authorised by a domain or carries a valid domain signature. It does not prove that every claim inside the message is true.
Explore this topicBIMI
Brand Indicators for Message Identification: a way to publish a brand logo for consideration by supporting inbox providers.
Explore this topicBIMI selector
The name used to locate a BIMI DNS record. Most deployments begin with default. It is separate from a DKIM selector.
Explore this topicCertificate authority (CA)
An organisation that issues digital certificates after performing the relevant validation. Mark certificates and web-server TLS certificates serve different purposes.
Explore this topicCMC
Common Mark Certificate. A mark certificate that can support eligible prior-use or modified registered marks, subject to issuer validation.
Explore this topicDKIM
DomainKeys Identified Mail. A domain-based digital signature that a receiving server can verify with a published public key.
Explore this topicDMARC
Domain-based Message Authentication, Reporting, and Conformance. Connects authentication to the visible From domain and publishes policy and reporting preferences.
Explore this topicDNS
Domain Name System. The distributed directory that publishes domain information, including email authentication and BIMI TXT records.
Explore this topicEnforcement
For BIMI deployment guidance, a DMARC policy requesting quarantine or rejection with full policy application, rather than monitoring alone.
Explore this topicEnvelope sender
The address supplied during SMTP delivery, commonly reflected in Return-Path. Its domain is used in SPF evaluation and can differ from the visible From address.
Explore this topicESP
Email service provider. A service that sends or manages email for an organisation. Using an ESP does not automatically align mail with your domain.
Explore this topicFrom domain
The domain in the sender address a person sees in an email. DMARC alignment is evaluated against this identity.
Explore this topicHTTPS
HTTP over a protected TLS connection. BIMI assets need public HTTPS hosting that a receiving provider can access.
Explore this topicMailbox provider
The service receiving and managing a recipient’s mail. It applies its own authentication, filtering, and logo-display rules.
Explore this topicMark
The brand symbol or artwork for which an organisation establishes rights. Eligibility depends on the certificate type and issuer requirements.
Explore this topicMVA
Mark Verifying Authority. An issuer that validates mark-related evidence for BIMI certificates.
Explore this topicOrganisational domain
The registrable domain associated with an organisation, such as example.com. It is not always simply the last two labels of a hostname.
Explore this topicPEM
A text encoding used to distribute certificate material. In BIMI, the public PEM asset contains the issued certificate and any required chain.
Explore this topicQuarantine
A DMARC policy requesting that failing messages be treated as suspicious, for example by placing them in spam. Receivers apply local policy.
Explore this topicReject
A DMARC policy requesting rejection of failing messages. Test legitimate sending sources before adopting enforcement.
Explore this topicSelf-asserted BIMI
A BIMI assertion without a mark certificate. Accepted by some providers, but insufficient for Gmail BIMI.
Explore this topicSPF
Sender Policy Framework. Publishes which sending servers are authorised for an envelope domain.
Explore this topicSVG Tiny PS
Scalable Vector Graphics Tiny Portable/Secure. The restricted vector-image profile used for BIMI logos.
Explore this topicTLS
Transport Layer Security. Protects network connections, including the HTTPS connection used to fetch BIMI assets.
Explore this topicTTL
Time to live. A DNS value that affects how long a resolver can cache an answer. It is separate from a mailbox provider’s logo cache.
Explore this topicTXT record
A type of DNS record containing text. BIMI uses it to publish its version and asset locations.
Explore this topicVMC
Verified Mark Certificate. A mark certificate for eligible registered or government marks; associated with Gmail’s verification checkmark.
Explore this topicNo matching terms. Try a shorter word, or browse all guides.