Device Central CS3 had libraries that were resident on your computer. Periodically, the libraries were updated and the updates offered for download. You would then download the update and install in on your local computer. CS4 is different. The libraries are hosted at Adobe. As such, they can update it on the fly and offer an much better customer experience.
If your ISP or IT security folks block inbound port 80 traffic (many trojans use this common port) or the ".dat" file type, you could be left with a very limited program. Remember, all the libraries are now at Adobe.com.
Bear in mind that your IT folks may not wish to open up their firewall in this way. If so, you may want to put Device Central on a stand-alone machine and handle your own connection to the internet and security.
Many thanks to Nandi at the Adobe support forums for the help on this matter.