Networking Bible

Appendix A. TCP - UDP Port Assignments

IN THIS APPENDIX

• Different port assignments are listed

Table A.1 lists many common ports in use for both the TCP and UDP protocols, under the Port column as T and U, respectively. The most widely used ports are typically found in the range 1 to 1023 and are referred to as the "well-known ports." A large range of port assignments are registered by vendors for specific applications. Over time, many of these port assignments become just as popular as well-known ports. Registered ports are found in the range 1024 to 49191. Finally, ICANN allows the remaining ports from 49152 to 65535 to be used either dynamically or for private assignments. Ports in the high range are not registered or assigned; they are for use by anyone at any time.

In many instances, TCP and UDP use the same numbers for the same protocol, but not always. Nor is a single protocol such as HTTP necessarily found on only one port assignment. There can be multiple ports assigned, and in the case of HTTP, the two common port assignments are not a contiguous range: both 80 and 8080 (for firewalls) are commonly used.

Table A.1. Well-Known Ports: 1 to 1023 Registered Ports: 1024 to 49191 Dynamic and Private Ports: 49152 to 65535 (unassigned)

Port	Assignment	Notes
Reference: www.iana.org/assignments/port-numbers. The list above is edited and is not as complete as the list of ports on this official site. Also, their list is updated on a regular basis.
0 - T, U	Reserved
0 - T, U	Shirt Pocket netTunes; ...