You could look into setting up a Windows Software Update Server (WSUS). This downloads the updates from Microsoft and you then deploy them locally. I believe WSUS is being/has been superceded by an other more up-to-date arrangement recently but I'm not sure so you might want to check
on linux there is a central update repository which does central update. its called apt-cacher and you can use it to cache any software installed via apt-get (a package management tool used in debian linux) and stores it locally in the apt-caher should anysystem on the network need same package. it would be downloaded from the apt-cacher instead. the process works smoothly and saves a lots of bandwidth.