:51
(TCP/UDP)
Reserved
Low RiskTCP/UDP — System & Infrastructure
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Port Overview
Port Number
51
Service Name
Reserved
Transport Protocol
TCP/UDP
Category
System & Infrastructure
Security Risk
Low
Port Range
Well-Known (0-1023)
What is Port 51?
Port 51 is marked as reserved in the IANA registry. Previously associated with IMP Logical Address Maintenance but no longer in active use.
TCP/UDP
System & Infrastructure
Security Considerations
Port 51 (Reserved) 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.