EmbeddingGemma 2: an open, lightweight multimodal embedding model
deepmind.google·6d ago
AI Engineering
Hacker News·Aug 10·5 min read
One Email, Three Identities: SPF, DKIM and DMARC Explained
TL;DR
Emails can have three distinct identities—Sender Policy Framework (SPF), DomainKeys Identified Mail (DKIM), and Domain-based Message Authentication, Reporting & Conformance (DMARC)—which can lead to confusion in email authentication. Understanding these identities is crucial for ensuring email security and deliverability.
✦ Why It Matters
Review your email authentication settings to ensure SPF, DKIM, and DMARC are correctly configured.
Key Takeaways
- Ensure your ESP is signing emails with your domain in DKIM.
- Regularly review DMARC aggregate reports for alignment issues.
- Use relaxed alignment for subdomains unless strict is necessary.
- Configure custom DKIM to prevent legitimate emails from landing in spam.
How It Works
SPF checks if the sending IP is authorized for the envelope domain, while DKIM verifies the message's integrity through a cryptographic signature. DMARC then assesses whether either SPF or DKIM aligns with the visible From domain, allowing for flexible email authentication.