TCP AND UDP PORT NUMBERS ARE divided into three ranges:
Well-known ports (0–1023)
Registered ports (1024–49151)
Dynamic/private ports (49152–65535)
Port numbers are 16-bit numbers, so the range of existing port numbers is 0–65535. In Solaris, in order to listen and accept connections on well-known ports (port range 0–1023), daemons need to run as root. These are assigned by the IANA and on most systems can be used only by system processes or by programs executed by privileged users. Ports are used in TCP to name the ends of logical connections that carry long-term conversations. For the purpose of providing ...