Downloading Ubuntu updates from a local system

[kalpana]

In our company we have +/- 25 Ubuntu Linux systems in use.
When new updates become available, they are downloaded and installed on all that 25 Ubuntu systems.
In the current configuration, those updates are downloaded on all 25 Ubuntu systems from a remote server.
E.g. http://nl.archive.ubuntu.com/ubuntu
This is configured in the file /etc/apt/sources.list
Of course, it is not practical to download a file containing an update 25 times from a remote system.
I want to set it up so that a file which contains the update, is downloaded once on a local update server.
Then the 25 Ubuntu systems can download the file, which contains the update, from that local update server.
However, I do not have space to set up a complete mirror of http://nl.archive.ubuntu.com/ubunu

Can anyone give my directions how I can set up and configure this?