Port 100 is not assigned to any specific service or application. It is therefore considered to be an unassigned or reserved port.
Ports those registered with IANA are shown as official ports. The same port number may be unofficialy used by various services or applications. The official usage are listed separately below its usage may change from time to time.
|Port||Protocol (TCP/UDP)||Title||Description||Port Type|
|Port 100||tcp||newacct||[unauthorized use]||WELL KNOWN PORT|
Unofficialy or sometimes with conflict, the same port may be used by different applications.