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Side-channel attacks (SCA) are capable of bypassing the theoretical protection of cryptographic schemes and revealing secret information in hardware devices. They have become a serious threat to the hardware security of the cryptographic modules. Entering the Internet of Things (IoT) era, it is crucial to verify the IoT devices' ability to thwart potential attacks from stealing confidential data. In this work, we set out to design and implement a framework for efficient SCA resistance verification. By integrating trace measurement equipment and GPU-accelerated analyzing engines, we have successfully built an automatic system which greatly simplifies the test procedure and enables on-the-fly SCA tests. Experiment results on common IoT development boards show both promising strength and flexibility of our framework to meet different testing requirements smoothly.

The security of the authentication scheme plays a more and more important role in today's web service systems as people's daily are increasingly depending on these services and user credentials are collected and stored online. An insecure authentication system will become a great threat for users' privacy. Beside security, usability is also very important for the design of an authentication system. Traditional password-based authentication solutions are often susceptible to various attacks due to the weak passwords chosen by incautious users. This paper illustrates a secure yet simple implementation, which uses digital signature algorithm to authenticate user identities. The proposed design brings usability and convenience to the authentication scheme by taking advantage of the increasingly widespread mobile devices. Full comparisons with existing systems in terms of their security, usability and deploy ability will also be presented in this paper.

Geographic routing yields scalable operation in Wireless Multihop Networks. Nodes forward packets to the destination either in a greedy manner, or along arbitrary curves from source to destination. The latter allows for higher robustness, as paths are adjusted to avoid, for instance, congested areas or non-cooperative nodes. However, determining working curves is either based on unreliable trial-and-error approaches or requires global network knowledge. We propose two local schemes that dynamically adapt the curve defining the packet forwarding at node level. Our first procedure uses cached curves, and the second one builds local maps at each node. We implement them for the case of planar graph routing with guaranteed delivery but they can also be easily adapted to greedy routing. We evaluate our schemes by means of simulation in constrained multihop networks, and show that they reduce transmissions up to 74% compared to existing solutions.

Cloud storage is one of the most rapidly growing cloud services, which at the same time also faces serious security challenges. Recently, several cloud-storage service providers started to provide encryption protection to client data in the cloud. However, encryption imposes significant limits on data use. In this paper, we report our design and implementation of an encrypted cloud storage system that supports multi-user secure indices, allowing efficient search among encrypted documents of multiple users. Experiment results show that keyword search can be performed in real time. We believe that our system represent a first step toward providing secure and useful cloud-storage services in practice.

Carrier aggregation in LTE-Advanced provides the capability to uncoordinatedly deploy home eNodeBs with the opportunity to autonomously mitigate the interferences. Among many improvement approaches, the autonomous component carrier selection (ACCS) scheme to improve the performance of the cell edge users worth our attentions. However, a poorly ordered execution of the carrier selection can lead to waste of radio resources in a typical home Internet access scenario. In order to address this issue, we propose a component carrier reselection scheme which ameliorates the total throughput of the eNodeBs by reselecting the carriers according to an intelligently planned order. Additionally, we also propose to improve the performance of the cell edge users with the low-complexity fractional power suppression technique. System-level simulation of the proposed schemes has shown substantial improvement over the original ACCS scheme.

Both the femtocell technology and the concept of mobile virtual network operators (MVNO) are believed to be key directions for future mobile network evolutions. This paper proposes a detailed model for the femtocell-based MVNO and analyzes the dynamics between the femto base station transmit power and its absorbing effect on the macrocell users via game theoretic techniques. The results show that the power settings given by the Nash equilibrium maintain the required QoS level without causing excessive interferences. Such numerical results should help the feasibility of large-scale deployment of femtocell-based MVNOs.

Among all related issues in shared wireless networks, the bandwidth allocation mechanism should be one of the most important ones that affect system efficiency, QoS, and the revenue of network operators. In this paper we present a model for the bandwidth resource sharing in a wireless access network among multiple mobile virtual network operators (MVNOs). Within this model, we propose an efficient scheme to adaptively allocate the bandwidth in accordance with the traffic fluctuation. Our proposed bandwidth allocation scheme adopts the technique of dynamic programming to maximize the expected total revenue across multiple stages from the perspective of the facility provider. Meanwhile, we also allow various MVNOs to compete for bandwidth resources by setting the prices. The design is then evaluated by simulation results and proved to be efficient and beneficial.