Implementation of a security structure based on IPsec in UFC-cooperative network

Abstract

Since 2005, our research team has researched U-TOPIA project aimed at realizing a campus-wide ubiquitous environment. In addition, we have developed a wearable computing platform, named Uibquitous Fashionable Computer (UFC). The user wearing a UFC can utilize many services in U-TOPIA. Some UFC users sometimes work together for a common goal. For example, users play the on-line game together. In this case, if one user`s battery power is gone, others cannot work, too. Therefore, in order to extend the lifetime of the group maximally, UFC-cooperative networking (CoNet) was proposed. The users of CoNet use their bluetooth interface for communication, keeping WLAN down so that they can save their energy. One of members use both WLAN and bluetooth interface, and transfer both his own packets and all slave`s packets. The former calls a slave, and the letter is a master. However, a master in CoNet forwards entire packets of all slaves. In contrast with conventional network equipments such as routes and gateways, a master has the entire TCP/IP layers. Therefore, a master can eavesdrop on and tamper with all packets of the slaves. As a result, slaves can be damaged by a malicious master such as slaves` important information is revealed and such as the winner of game is changed. Like this, the CoNet system internally has the security problems. In order to solve the security problems, we propose the method to encrypting and authenticating the communication channel between an AP and slaves. Encryption and authentication provides data con??dentiality and integrity to packets of slaves. To implement the proposed method, we utilize the IPsec standard, and modify it in order to use in CoNet. In addition to this, we proposed the reputation management system to detect a malicious master and calculate its reputation. By using this reputation, we can expel the malicious master from the CoNet group, and can deny it to rejoin CoNet. Related to the energy consumption, C...