Identifier Alignment
Identifier Alignment
- April 21, 2021
- Posted by: Nicola Selenu

Identifier alignment is a requirement formulated in DMARC that imposes extra conditions on the identifiers used by the DKIM and SPF protocols. Specifically, it requires that any domain identifiers used by the authentication checks these protocols perform must also match or align with the RFC5322.From header (commonly referred to as the “header From:”) in order for a “pass” in the other protocols to result in a DMARC “pass.”. The alignment may be “strict,” meaning an exact match, or “relaxed,” allowing a subdomain in one identifier to match the same parent domain in the other.
Author:Nicola Selenu
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- Term: Identifier Alignment
- Term: Authentication
- Term: From Header
- Term: Subdomain
- Term: Alignment
- Term: RFC5322
- Term: Domain Message Authentication Reporting & Conformance (DMARC)
- Term: Header
- Term: DomainKeys Identified Mail (DKIM)
- Term: Sender Policy Framework (SPF)
- Term: Email Service Provider (ESP)
- Term: Deliverability
- Term: SpamAssassin
- Term: Extended Simple Mail Transfer Protocol (ESMTP)
- Term: Simple Mail Transfer Protocol (SMTP)
- Term: Domain Name System (DNS)
Identifier Alignment
Identifier alignment is a requirement formulated in DMARC that imposes extra conditions on the identifiers used by the DKIM and SPF protocols. Specifically, it requires that any domain identifiers used by the authentication checks these protocols perform must also match or align with the RFC5322.From header (commonly referred to as the “header From:”) in order for a “pass” in the other protocols to result in a DMARC “pass.”. The alignment may be “strict,” meaning an exact match, or “relaxed,” allowing a subdomain in one identifier to match the same parent domain in the other.
« Back to Glossary Index- Term: Identifier Alignment
- Term: Authentication
- Term: From Header
- Term: Subdomain
- Term: Alignment
- Term: RFC5322
- Term: Domain Message Authentication Reporting & Conformance (DMARC)
- Term: Header
- Term: DomainKeys Identified Mail (DKIM)
- Term: Sender Policy Framework (SPF)
- Term: Email Service Provider (ESP)
- Term: Deliverability
- Term: SpamAssassin
- Term: Extended Simple Mail Transfer Protocol (ESMTP)
- Term: Simple Mail Transfer Protocol (SMTP)
- Term: Domain Name System (DNS)
Author:Nicola Selenu
Email Service Providers Handbook
The most comprehensive “Handbook of Email Service Providers“!
SPAMASSASSIN RULES
All SpamAssassin rules in one place, EXPLAINED!
SMTP COMMANDS
& REPLY CODES
All SMTP/ESMTP commands and reply codes in one place, EXPLAINED!
Free DNS Tool
Check the DNS records of your domain with our free DNS tool.
Deliverability Glossary
The most comprehensive Email Deliverability and Marketing Glossary!
« Back to Glossary Index- Term: Identifier Alignment
- Term: Authentication
- Term: From Header
- Term: Subdomain
- Term: Alignment
- Term: RFC5322
- Term: Domain Message Authentication Reporting & Conformance (DMARC)
- Term: Header
- Term: DomainKeys Identified Mail (DKIM)
- Term: Sender Policy Framework (SPF)
- Term: Email Service Provider (ESP)
- Term: Deliverability
- Term: SpamAssassin
- Term: Extended Simple Mail Transfer Protocol (ESMTP)
- Term: Simple Mail Transfer Protocol (SMTP)
- Term: Domain Name System (DNS)