Definition
Email authentication consists of three DNS-based records that work together to verify sender identity. SPF (Sender Policy Framework) lists which servers are authorised to send mail for your domain. DKIM (DomainKeys Identified Mail) adds a digital signature that proves the email has not been tampered with. DMARC (Domain-based Message Authentication, Reporting, and Conformance) tells ISPs what to do when SPF and DKIM checks fail. All three are required for best deliverability, and major ISPs now enforce DMARC for high-volume senders.
Related Glossary Terms
AOL Mail for Email Marketers
AOL Mail is a legacy email provider with specific deliverability requirements and rendering quirks, now operating as part of the Yahoo+AOL network under shared infrastructure.
BIMI
BIMI (Brand Indicators for Message Identification) is an email standard that allows brands to display their logo next to their emails in supported email clients. It requires DMARC enforcement at quarantine or reject policy.
Bounce Rate Threshold
A bounce rate threshold is the percentage of hard or soft bounces at which email platforms and ISPs begin to penalise sender reputation, typically around 2-5%.
Bounce Rate
Email bounce rate is the percentage of emails that were rejected by the receiving server before reaching the recipient. It is a key indicator of list health and data quality.
Bulk Email Marketing
Bulk email marketing is the practice of sending a single email campaign to a large list of subscribers simultaneously, typically for promotional, newsletter, or announcement purposes.
Email Deliverability
Email deliverability is the ability to land in the recipient's inbox rather than the spam folder. It depends on sender reputation, authentication, list quality, and content practices.