Cryptographic protocols for confidentiality are oblivious to the unique challenges and advantages that wireless communication presents, mainly due to the open and public medium. We design a protocol at the wireless-specific physical and link layers and build a system that is information-theoretically secure against eavesdropping. Leveraging both friendly jamming and signal cancellation, Noah offers a novel keyed noise ooding protocol for wireless confidentiality. In contrast to prior work in wireless security, Noah protocol and its security properties are independent of the individual receiver's channel and do not require the channel link information (such as the channel condition and the antenna location) on the transmitter side. Thus, Noah supports multicast, taking advantage of the inherent broadcast nature of wireless medium, and defeats advanced channel-controlling eavesdroppers by making it impossible to physically separate the transmission and jamming. In this paper, we present the Noah protocol and provide fundamental insights in jamming and rate control for designing Noah.