TCP/IP Application Assignments and Server Port Number Ranges

The port numbers I just discussed provide a method of transport layer addressing that allows many applications to use TCP and UDP simultaneously. By specifying the appropriate destination port number, an application sending data can be sure that the right process on the destination device will receive the message. Unfortunately, there's still a problem to be solved.

Let's go back to using the World Wide Web. You fire up a web browser, which is client software that sends requests using HTTP. You need to know the IP address of the website you want to access, or you may have the Domain Name System (DNS) supply the IP address to you automatically. Once you have the address, the web browser ...

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