Network & Email · page 20

Plans phased none, quarantine, reject progression with exit gates.

Explains aggregate XML fields like sources, counts, and alignment results.

Formats mailto rua URIs with size limits and multiple destinations.

Plans BIMI record, SVG, and VMC requirements for logo display.

Builds the _mta-sts TXT fields and a policy file skeleton.

Plans testing then enforce mode staging for MTA-STS.

Generates the _smtp._tls rua reporting record.

Plans Outlook autodiscover CNAME and SRV records per domain.

Plans MX preference ordering and fallback host lists.

Checks when secondary MX hosts hurt spam filtering and queueing.

Plans envelope-from domains and subdomains versus visible From headers.

Clarifies From, Reply-To, and Return-Path roles in a reference table.

Generates VERP return-path patterns per list and recipient.

Plans bounce address tag validation scheme and key rotation.

Plans SRS prefix schemes and domains for forwarded mail.

Explains why forwarded mail fails SPF and lists alignment fixes.

References ARC-Authentication-Results, headers, and sealing flow.

Parses pasted headers into a hop table with delays and auth results.

Decodes from, by, with, and via fields on each hop line.

Explains client and MTA fingerprint clues in headers.

Maps 4.x and 5.x enhanced status codes to causes and actions.

Explains 2xx, 4xx, and 5xx semantics and retry rules.

Plans retry intervals that pass greylisting within windows.

Checks anti-NDR steps that stop backscatter to spoofed senders.