What is the principle of the proxy server?

Question

Computer networks

The scheme is as follows, the Internet adsl cable goes to the cisco 2811 router, from the router it goes to the cisco switch too, from the switch to the patch panel, BUT there is also a freebsd proxy server system unit from which one rj45 cable goes to the switch, and I don’t understand how does the proxy work? poluchaetsya tsiskvsky router asks via svtch proxy server permissions?
At the expense of proxy settings, they are not specified not in the browser, not in the network settings of the browser, or anywhere, who knows who will tell you the principle of this functionality?

Answer 1

Not permission.
All requests to the Internet go non-arbitrarily, but
1 The workstation sends the URL to the proxy server
2 The proxy server sends this URL to the Internet on its own behalf
3 The result returns to your workstation.
Cisco is most likely configured to redirect ports 80 and 443 ports (http, https protocols) for all machines to this freebsd, where a proxy server is raised.
A proxy server allows you to:
View ALL requests from users who use it.
Configure access for users by URL mask.
Configure access for users by time, by group.
etc...

Answer 2

I didn’t see something in this food chain how the freebsd PC gets the Internet, just one link from freebsd to the switch and that’s all) so you need to look where and how it works, and if there are no proxy settings on the PC, then it means that the freebsd PC is not proksya