Apt-Cacher NG is a caching HTTP download proxy for software packages, primarily made for Debian/Ubuntu clients but also usable with OpenSUSE and Cygwin archive mirrors. The main principle is that a central machine hosts the proxy for a local network, and clients configure their APT setup to download through it. Apt-Cacher NG keeps a copy of all useful data that passes through it, and when a similar request is made, the cached copy of the data is delivered without being re-downloaded. More