Examples of downword and upword communication?

Answer 1

In an internet environment (it is important to qualify your question) the machine containing the desirable data is considered the server (even though both machines will act as client and server, for purposes of disambiguation and simplificaton we will maintain this definition). The machine used to access the desirable data is the client. When the client requests data from the server the terminology used to express this action is "download." As in, you are loading code down from the server. A common example of this is the text file received from the server that explains to the client's webbrowser how to properly render the page. The terminology used to describe data moving from the client to the server is "upload." The most common upload is a page request from a web server. When you type in a URL into your address bar and click "Go" or press return a string is inserted into a data packet. This packet can be thought of as a theoretical container holding the data. The data is in the form of an ASCII string similar in structure to "/resourcedesired.extension". The domain is included but only in the header portion of the packet that tells routers where to send it. That is like the postal address written on the package. And just as a package could go to one of many people in the building it is destined for and would be sorted in the mailroom, a server can host multiple domains and will use this information to sort this out and have the appropriate process respond. The data uploaded is the entire request. I just made it lengthy so people would have to understand it and couldn't just copy and paste for homework. Hope this helps.