What Is a Port Number?
If you see an address like 66.33.209.103:10200 or haxial.com:500, then the port number is the number after the colon ‘:’. So in those examples, the port numbers are 10200 and 500 respectively. Port numbers are generally used to distinguish between the different services/programs that may be running on a computer. You can think of this like a block of apartments/units which all have the same street address, so in order to distinguish between the different apartments, you write an address like: Apartment 5, 12 Main Street. For example, the address of your computer may be 10.20.30.40, but you may be running both KDX Server and a Web Server. Therefore if you wanted to connect to the KDX Server, you would use 10.20.30.40:10700, whereas if you wanted to connect to the Web Server, you would use 10.20.30.40:80. A port number is required for all addresses, but often you can omit it, and whatever program you are using will automatically add whatever the default port number for that program is. F
Requested and Answered by Carnuke on 2004/12/19 7:40:04 (3280 reads) Where port numbers are concerned, consider an analogy between the computer and the telephone. Port numbers and their associated network addresses work something like telephone numbers and associated network extensions, or channels. In this analogy a port number represents the “channel” for network communications. Port numbers allow different applications on the same computer to utilize network resources without interfering with each other. Just as different organizations may use different extension numbers “inside” their primary phone number, different computers use the same set of port numbers. Port numbers most commonly appear in network programming, particularly socket programming. Sometimes, though, port numbers are made visible to the casual user. Normally, a Web site uses port number 80 and this number need not be included with the URL (although it can be). In IP networking, port numbers can theoretically range
