It's a private network that follows standards set by RFC 1918 for IPv4. Devices set up on RFC 1918 space are not on the public Internet and are more protected from outside or third-party misuse. RFC 1918 is particularly useful for printers and multi-function devices, although any device that does not need to be in the public Internet can go there.
When you request that devices be moved to RFC 1918 space, you are requesting a new workgroup for your department on the private network.
To set this up, the data networking engineers need to know the following information:
The MID where you want the workgroup created
The building names where the the devices will be located
The total number of IP addresses per building
With the correct permissions in Service Gateway (IP Management), you can request this by going to "Request Services" and submitting the above information.
If you do not have Service Gateway access, request a workgroup on RFC 1918 space by sending the request and the above information to firstname.lastname@example.org.
For more information on private networks, as well as private network space for IPV6, see the Wikipedia article.