Constructing secure group communication over wireless ad hoc networks based on a virtual subnet model

Recently, more and more people have begun using mobile devices such as PDAs and notebooks. Our lives have been profoundly affected by such devices. A MANET, a mobile ad hoc network, is an effective networking system facilitating an exchange data between mobile devices, without the support of wireless access points and base stations. A MANET is not restricted to unicast or multicast communication, but can also provide "many-to-many" transmission, which can be treated as a group communication. Until recently, however, the way in which such groups are formed had not drawn much attention. Because communication in wireless networks is broadcast and a certain amount of devices can receive transmitted messages, the risk of unsecured sensitive information being intercepted by unintended recipients is a real concern. Consequently, efforts to ensure the security of group communications in MANETs are essential. This article proposes a virtual subnet model to construct secure group communication over a MANET. With the model, the composition of groups is established as the forming of group keys. Our results show that this approach can completely satisfy the needs for both security and efficiency.