989 ftp protocol, data, over TLS/SSL - System Port

989 is a System Port. Transport Protocol TCP UDP , 989 Service Name ftps-data, Service Name Description: ftp protocol, data, over TLS/SSL.

Port	Protocol	Service Name	Description	Source
989	TCP UDP	ftps-data	ftp protocol, data, over TLS/SSL	IANA
989	TCP UDP		FTPS Protocol (data): FTP over TLS/SSL,Official	wikipedia
989	TCP UDP		Mac OS X RPC-based services, Used by NetInfo, for example	Apple.com
989	TCP UDP	ftps-data	ftp protocol, data, over TLS/SSL	bekkoame

Port	Service Name	Description
762	quotad
964		Unassigned
1164	qsm-proxy	QSM Proxy Service
1226	stgxfws	STGXFWS
1822	es-elmd	es-elmd
2844	bpcp-poll	BPCP POLL
3416	commandport	AirMobile IS Command Port
3952	i3-sessionmgr	I3 Session Manager
4952	sagxtsds	SAG Directory Server
5110		Unassigned

A port is an endpoint of communication in an operating system. While the term is also used for hardware devices, in software it is a logical construct that identifies a specific process or a type of service.

Port numbers are assigned in various ways, based on three ranges: System Ports (0-1023), User Ports (1024-49151), and the Dynamic and/or Private Ports (49152-65535);

The Well Known Ports are assigned by the IANA and on most systems can only be used by system (or root) processes or by programs executed by privileged users. Ports are used in the TCP [RFC793] to name the ends of logical connections which carry long term conversations. For the purpose of providing services to unknown callers, a service contact port is defined. This list specifies the port used by the server process as its contact port. The contact port is sometimes called the "well-known port". To the extent possible, these same port assignments are used with the UDP [RFC768]. The range for well-known ports managed by the IANA is 0-1023.
DYNAMIC AND/OR PRIVATE PORTS Registered Ports are those from 1024 through 49151.
The Dynamic and/or Private Ports are those from 49152 through 65535