Hardened CryptographicBaseline.
What receiving mail servers see.Every domain we deploy is engineered to pass strict RFC criteria before handoff:
Flattened, single-include architecture. Lookup depth locked at ≤ 2 (RFC limit: 10).
Dedicated 2048-bit RSA keys per subdomain.
Strict domain alignment enforced with active RUA aggregate reporting.
TLS 1.3 enforced across all custom tracking CNAME records with automated HTTP-to-HTTPS redirection.