What is SIPRnet?
SIPRNet, or , is a global United States military network system used for transmitting classified information, intelligence, targets, and messages at the secret level.
SIPRnet support the various system such as the Global command systems and defense messaging system and also some other important planning documents over the secure path. it is based on the some method that are use for ordinary internet access but the main difference is that it has some dedicated path lines that are not seen in other communication systems. These lines are responsible for managing the secure communication with highly authenticated user access.
In other words, SIPRNet is completely parallel Internet, uses the same communications procedures and has been kept separate from the ordinary civilian Internet.
Approximately 3 Million people with secret clearances have access to SIPRNet, which includes Pentagon and military officials, Intelligence agencies, FBI, as well as diplomats in US embassies all around the World.