lookup> port 55

55 ·Port

ISI Graphics Language (tcp/udp).

tcpudpisi-gl
Status55
Serviceisi-gl
Protocoltcp / udp
Well-knownYes (0–1023)

What runs on port 55?

ISI Graphics Language (tcp/udp).

Well-known ports are assigned by IANA to system-level services; binding them usually requires administrative privileges.

RangeExplanation
Well-known (0–1023)Reserved for system services; binding usually requires admin privileges.
Registered (1024–49151)Available to user applications; IANA registers common services here.
Dynamic / private (49152–65535)Used for ephemeral client connections.

Is port 55 TCP or UDP?

A port number is a transport-layer address used independently by TCP and UDP; isi-gl typically runs over its documented transport protocol.

Can I change what runs on port 55?

Yes — most services let you configure the listening port, but make sure clients and firewalls are updated and you avoid conflicts.

Common services

Related headers

Related status codes