209
QMTP
Low RiskTCP — Email
Port Overview
Port Number
209
Service Name
QMTP
Transport Protocol
TCP
Category
Email
Security Risk
Low
Port Range
Well-Known (0-1023)
What is Port 209?
QMTP (Quick Mail Transfer Protocol) is a replacement for SMTP designed for high-performance mail transfer between cooperating mail servers. Designed by Dan Bernstein. Very limited adoption.
TCP
Email
Security Considerations
Port 209 (QMTP) is classified as low risk. This service uses encryption or has a minimal attack surface, making it relatively safe to expose.
Recommendation: Standard security practices apply. Keep software updated and monitor access.