suppose I want to test a server's and its web application's ability to handle many simultaneous connections well and show decent latency. So ideally I would want a thousand machines to bombard it with usage requests, but that's not practicable. So instead, can I just make a testing script with a thousand threads to run on the same server and have them perform the testing, connecting to the server via a geographically far-away proxy? My reasoning here is that the signal will have to travel realistically big distances to the proxy and back, so that sort of emulates the reality of real clients accessing the server.

Then again, to take this one step further, are there prepackaged emulators/frameworks that could perform a similar test without using internet at all, just simulating the latency of the network, realistically creating all the socket connections and other resource intensive stuff etc?