89
SU/MIT Telnet Gateway
Low RiskTCP — Remote Access
Port Overview
Port Number
89
Service Name
SU/MIT Telnet Gateway
Transport Protocol
TCP
Category
Remote Access
Security Risk
Low
Port Range
Well-Known (0-1023)
What is Port 89?
Port 89 was assigned to the SU/MIT Telnet Gateway, an early ARPANET service that provided mediated Telnet access through a gateway system at MIT and Stanford.
TCP
Remote Access
Security Considerations
Port 89 (SU/MIT Telnet Gateway) 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.