Syncronicity

 

The Problem

The students at Carleton College often take public computing for granted. With over 260 public machines in place across campus, the need to have one's personal computer on hand is unneccessary. While many other campuses opt to use a lock-down model where users have no control over installing their own applications, Carleton offers complete freedom to its students to install whatever they need.

Carleton is able to adopt this luxary through the use of a clever application called PC-Rdist. PC-Rdist works on a given lab computer by running at shutdown and comparing the computer's current filesystem and registry contents against an index stored on a server. By keeping these indices on a centrally-located server, we elegantly maintain an orderly computer environment between users while at the same time gain the ability to push new software and updates out to lab computers in an unobtrusive manner.

But PC-Rdist is Broken

As it turns out, ever since Windows Vista introduced a new security model and compatibility mode for running legacy software, PC-Rdist has no longer been able to run on Windows. While the filesystem and registry virtualization has allowed many legacy applications to function smoothly on modern computers, this technology disables the very functionality of PC-Rdist.

How to Fix Things

Through our use of modern filesystem access calls that honor the security model, and our novel way of accessing the registry which circumvents the redirection methods put in place by the new security model, we've made progress in re-establishing PC-Rdist's model in public lab administration.