We have a wonderful IT General Computer Control network diagram example built in the Microsoft program, Visio, available for complimentary download available via this link after registration.
Registration is available at the top of the page or by clicking the registration link above which will take you back to the home page where you may easily register.
You must have Visio or at least download the free 2003 Visio Viewer from Microsoft available via this link:
The diagram can be used for general documentation efforts or for compliance purposes (Cobit controls) and is a great head start for someone trying to understand how to complete a network diagram.
We hope you enjoy this information and find it useful.