We want to be sure we grasp the relationship of clients to servers,
and have a shared vocabulary of terms.
It is the interaction between two programs when they communicate across a network. A program at one site sends a request to a program at another site and awaits a response.
A client-server network is a computing model in which multiple clients connect to a central server to access resources, such as files, applications, and data. The server acts as a central hub, managing and providing services to the connected clients.
The requesting program is the client.
Mac users
Mac vs. Windows: Which Is Right for You?The lecturer will use a Windows OS (desktop or laptop) most of the time. On occasion, the interface in Windows will not match the interface in a Mac. While we will try to have examples for all operating systems, it will be useful if, when you find that the Mac view is different, that you take a screenshot of the Mac environment and send it to the instructor. The instructor will ensure that the Mac screenshot is integrated into the class pages pertaining to the situation in which the screenshot was taken.
The program satisfying the request is the server.
For example, SDIS has a number of servers, for a number of purposes (as of 27 May 2025).
| Internet Protocol (IP) Address | Name | specific function |
|---|---|---|
| 152.2.11.77 | citap.unc.edu | Center for Information, Technology, and Public Life website |
| 152.2.11.761 | citap-test.ils.unc.edu | Center for Information, Technology, and Public Life website |
| 10.4.80.7 | db1.ils.unc.edu | course database server |
| 10.4.80.5 | db2.ils.unc.edu | course database server |
| 152.2.11.70 | opal.ils.unc.edu | course accounts server, student projects |
| 152.2.11.74 | ruby.ils.unc.edu | web server, DB server |
| 152.2.11.81 | SDIS-jasrv.ad.unc.edu | research server |
| 152.2.11.78 | SDIS-pelican.ad.unc.edu | print server, admin tools |
| 54.160.244.144 | topaz.ils.unc.edu | research server |
| 34.206.160.36 | video.ils.unc.edu | research server |
Assuming we want to retrieve something from a server over the web, we might want to know how web servers work.
Client-server interaction is the basis of distributed computing
