Related work
XCIM is intended to complement—not replace—the deployed email authentication and policy ecosystem.
| Mechanism | What it establishes | Relationship to XCIM |
|---|---|---|
| SPF | Authorized sending hosts for a domain | Remains part of message authentication |
| DKIM | Domain-associated message signatures | Protects message integrity; XCIM adds consent evidence |
| DMARC | Identifier alignment and domain policy | Continues to govern domain authentication policy |
| ARC | Authenticated handling chain | Can preserve authentication context through intermediaries |
| One-click unsubscribe | Standard unsubscribe interaction | Addresses recipient opt-out, not portable grant verification |
| OpenID Connect | Authentication and identity claims | Candidate basis for issuer-hosted authentication flows |
| Certificate Transparency v2 | Auditable certificate logs | Provides design precedent for public append-only evidence |
References describe conceptual relationships. They do not imply endorsement, standards-track status, or interoperability with XCIM.