A method for providing secure communications among a plurality of ad hoc devices includes authenticating one or more first devices within a first network; authenticating one or more second devices within a second network; transmitting a group key to the authenticated first devices and to the authenticated second devices; establishing an ad hoc network by at least one of the authenticated first devices and at least one of the authenticated second devices using the group key; and communicating within the ad hoc network among the at least one of the authenticated first devices and the at least one of the authenticated second devices.