Authentication and transport limits
05This historical specification includes authentication mechanisms that do not provide modern transport confidentiality.
Terms in this drawing
Related RFCs and changes
“Updates” changes part of an earlier RFC. “Obsoletes” replaces it. This list shows selected related documents.
DIAGRAM§ 13 ↗
RFC 1939 · § 13EXAMPLE
3 / 3
03
Separate identity and retrieval
Authentication establishes account access; retrieval remains a maildrop operation.
Protocol participantThreat or exceptionProtocol controlSimplified drawings · precise section references
Read the updated RFC section ↗
USER/PASS can expose credentials without a protected channel.
- USER/PASS can expose credentials without a protected channel.
- The original APOP MD5 challenge-response is not a substitute for modern TLS guidance.
- Use later mail-access security guidance when deploying POP3.
Examples are illustrative. Consult the linked RFC and its errata for implementation details.
Read the RFC section ↗Diagrams simplify the RFC. Read the linked sections for complete requirements.
Privacy