IP ranges and domains permitted for direct relay.
Mandatory use of TLS for both SUBMISSION (port 587) and IMAPS (port 993) to protect data in transit. 3. Protocol Compatibility US MAILACCESS.txt
The US-MAILACCESS.txt document serves as a foundational specification for controlling access to mail server resources within the US-domain network architecture. It bridges the requirements of legacy systems (like IMAP2bis) with modern encryption standards to ensure secure message handling across distributed nodes. IP ranges and domains permitted for direct relay
Support for secure handshake protocols, ensuring that only authenticated clients can query the mail store. Protocol Compatibility The US-MAILACCESS
This draft assumes familiarity with ARPA standard mail formats (RFC 5321/5322). It is intended to be used in conjunction with localized firewall rules to restrict access to proprietary mail servers, especially for systems that require specific restricted IP source addresses or browser-based logins.