675 DCTP - System Port | Service Name:dctp

675 is a System Port. Transport Protocol TCP UDP , 675 Service Name dctp, Service Name Description: DCTP.

Port	Protocol	Service Name	Description	Source
675	TCP UDP	dctp	DCTP	IANA
675	TCP UDP		Mac OS X RPC-based services, Used by NetInfo, for example	Apple.com
675	TCP UDP	dctp	DCTP	bekkoame

Port	Service Name	Description
496	pim-rp-disc	PIM-RP-DISC
1944	close-combat	close-combat
3726	array-manager	Xyratex Array Manager
4482		Unassigned
4916		Unassigned
6837		Unassigned
7001	afs3-callback	callbacks to cache managers
7865		Unassigned
8044	fs-mgmt	FireScope Management Interface
8049		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