285 Unassigned - System Port

285 is a System Port. Transport Protocol , 285 Service Name , Service Name Description: Unassigned.

Port	Protocol	Description	Source
285		Unassigned	IANA
285		Delf	simovits.com
285	TCP UDP	Unassigned	bekkoame

Port	Service Name	Description
2015	cypress
3731	smap	Service Manager
4757		Unassigned
5320	bsfserver-zn	Webservices-based Zn interface of BSF
5996		Unassigned
6551	sum	Software Update Manager
6630		Unassigned
8841		Unassigned
9011		Unassigned
9334		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