Not "parallel" but a few networks. NIPR - Unclassified DoD internet plus powerful defensive capabilities when traffic goes between the intranet and public inte

Not "parallel" but a few networks. NIPR - Unclassified DoD internet plus powerful defensive capabilities when traffic goes between the intranet and public internet. SIPR - Private "internet" for military and defense contractors and such to allow for handling SECRET and below. Dedicated circuits. JWICS - Like SIPR but for TS and SCI channels. Then other dedicated networks for international partnerships which run on dedicated circuits and using sats.