A Private networks is called an intranet, this can range from your home network to corporations, governments and other organisations. There are many
types and sizes around. The Internet is a public network where anyone can link in.
There are Intranets, as was posted earlier. Used by private companies and also a specific military base may have it's own Intranet as well for
command members.
There is also SIPRNET, a classified network (up to Secret) used by the military and DOD elements. PFC Manning downloaded all the info he passed to
Wikileaks from SIPRNET and JWICS. The majority of the info processed on SIPRNET is actually unclassified, or Official Use Only. JWICS is the TS
counterpart to SIPRNET.