Secure communications and data management in ubiquitous services (2009)

In the last few years, we have observed an explosive growth of ubiquitous computing, which is emerging as the next generation information technology. This new paradigm has been embodied into tremendous service models through numerous ubiquity-related technologies, such as web, ad hoc, sensor networks, and ambient intelligence to provide computing and communication services anytime and anywhere. Parallel to this, wireless communication technologies have evolved to a stage where they are capable of connecting cyber and physical domains. In such an era, computers in the traditional sense gradually fade from view, making information and communication mediated by computers available anywhere and anytime through devices that are embedded in our environment, completely interconnected, intuitive, effortlessly portable, and constantly available. Although ubiquitous service presents exciting enabling opportunities, the benefits will only be reaped if security aspects and data management can be appropriately addressed. As a result, to realize the advantages of ambient intelligence and services in ubiquitous environments, it requires the security issues and data management to be suitable for its applications. Therefore, secure communication and data management are important challenges for commerce, the public sector, academia and for the individuals. For example, threats exploiting infirmities of user interfaces, operating systems, networks, and wireless communications give rise to new concerns about loss of confidentiality, integrity, privacy, and availability. How can these risks be avoided to an acceptable level? This special issue is intended to foster the dissemination of state-of-the-art research in the area of secure ubiquitous services including security models, security systems, secure data management, and novel applications associated with its utilization wherein security and privacy are the indefeasible rights of individuals to control the ways in which personal information is obtained, processed, distributed, shared, and used by any other entity. This special issue includes eight papers from researchers in Taiwan, China, Tunisia, Canada, Korea, Germany, Hong Kong, and Mexizo, who have demonstrated the effectiveness and efficiency of a variety of secure communications, theory, optimizations, service models, and applications in different areas of ubiquitous and mobile computing. The papers selected for this issue not only contribute valuable insights and results but also have particular relevance to the communication and security computing community. All of them present high-quality results for tackling problems arising from the ever-growing wireless and ubiquitous services. H. Eltaief and H. Youssef in their paper entitled ‘multi-layers connected chains (MLCC): A new hash-chained mechanism for multicast source authentication’ present a new mechanism for multicast data source authentication based on signature amortization. They introduce a new hash chain construction mechanism called MLCC. It is an amortization mechanism that seeks to achieve a strong resistance against packet losses while reducing the overhead. The MLCC mechanism constructs multiple connected chains, where each chain connects some packets together which are arranged in layers. Increasing the number of chains, the number of packets per chain or both for MLCC improves packet loss resistance and reduces the overhead. Their approach achieves a stronger resistance against packet losses and higher authentication probability. The paper by Dong Yang, Yu-xiang Zhang, Hong-ke Zhang, Tin-Yu Wu, and Han-Chieh Chao entitled ‘Multi-factors-oriented study of P2P Churn’ presents a performance evaluation framework and the performance model of P2P Churn. They analyze in detail various Churn factors such as number of peers, visitation periods of peers, joining frequency of peers, time to live of peers, retransmission times of the query failure, interval of the query failure, lookup latency, lookup accuracy rate, and bandwidth consumption. Based on the evaluation framework and the performance model, the authors analyze three P2P protocols, Chord, Kelips, and Tapestry to verify the capability of these protocols under Churn, the advantage of Chord over others, and the most important factors impacting Churn. Finally, they propose a novel technique to optimize the P2P Churn model. The paper by Ching-Hsien Hsu, Chi-Guey Hsu, Shih-Chang Chen, and Tai-Lung Chen entitled: ‘Message transmission techniques for low traffic P2P services’ presents different message transmission strategies to reduce the network traffic of enquiry messages and to increase the resource utilization. The proposed techniques are simple, with low complexity and are easy to implement. The experimental results show that the proposed methods are significant in reducing the network traffic under different unstructured P2P overlay networks. The proposed methods efficiently reduced the number of querying and provided reasonable message coverage for different decentralized unstructured P2P overlay networks. Analyses are given to weigh pros and cons of each method with different scenarios. The paper by Peng-Wei Tian, Yao-Xue Zhang, Yue-Zhi Zhou, Laurence Tianruo Yang, Ming Zhong, Lin-KaiWeng, and Li Wei entitled ‘A novel service evolution approach for active services in ubiquitous computing’ proposes a novel service reuse approach for the service evolution process in the active services paradigm. Besides the entire service reuse realized in the existing works, the proposed approach can also achieve partial reuse of the existing services at the functional level. To generate a user-needed service, a functionality-based index strategy was built to accelerate the service reuse process. To accomplish the demand of quality of service (QoS) in ubiquitous services, based on the general service evolution process, two types of QoS-aware service generation methods are also introduced. The experimental results demonstrated the superiority of the proposed methods in terms of computation cost, success rate, and the quality of generated services. The paper by Binod Vaidya, Tai Hoon Kim, Jong Hyuk Park, and Young Jae Lee entitled ‘Secure ubiquitous connectivity in hybrid multipath wireless ad hoc network’ presented a secure architecture framework for ubiquitous connectivity in hybrid multipath mobile ad hoc network (MANET) that provides secure foreign agent (FA) discovery as well as a secure Mobile IP registration for mobile node. Performance analysis shows that the proposed scheme is robust against various attacks in Internet connectivity and ad hoc routing. Compared with the existing schemes, the proposed framework is quite susceptible to some Internet attacks during registration such as the fake registration and forged FA. Overall, the proposed scheme has a better performance in the re-authentication process. The paper by M. Ge, K. Y. Lam, D. Gollmann, S. L. Chung, C. C. Chang, and J. B. Li entitled ‘A robust certification service for highly dynamic MANET in emergency tasks’ tackles issues critical to asymmetric key management in MANET, which almost invariably serves as a basis of security services in a network environment. To address the deficiencies of the existing key management schemes, the authors propose the concept of mission-specific certificates to manage public keys. For issuance and/or revocation of mission-specific certificates, a mission-specific certificate authority (MCA), which consists of a collection of server nodes to operate the threshold cryptographic scheme, is proposed. Furthermore, to cater for the occurrence of network partitioning, which is common in highly dynamic MANET, they propose a partition-tolerant mechanism for MCA by introducing the notion of auxiliary server nodes. The authors discuss the security and performance of the proposed scheme and show that it is a secure and partition-tolerant mechanism which can effectively improve the availability of the MCA. The paper by Luis E. Palafox and J. Antonio Garcia-Macias entitled ‘Deploying a voice capture sensor network system for a secure ubiquitous home environment’ presents a novel voice capture sensor network architecture and a data recollection mechanism that allows node redundancy for reliability and eliminates data redundancy at the same time. Additionally, under the same recollection scheme, the authors provided basic security services to expand the number of possible scenarios on which their deployment could be applied. It is also demonstrated that by deploying a small network consisting of four nodes cluster, the nodes' lifetime can be significantly improved compared with the traditional capture–send approach. On a larger scale, they demonstrated the technical feasibility of implementing a distributed speech capture system using a WSN. Additionally, they tested the reach and limitations of their approach through experimental evaluations. The paper by Yiliang Han and Xiaolin Gui entitled ‘Adaptive secure multicast in wireless networks’ proposes an adaptive framework and technologies to construct the multi-recipient signcryption scheme. The framework provides separate or joint encryption and signature functions according to users' identities and requirements transparently, and has the ability to aggregate multiple unicast besides the common multicast service. The framework is suitable for all of the adaptive signcryption schemes. The construction technologies are generic methods that could be used to design the other schemes also. The proposed scheme can reduce overhead efficiently, while keeping the high-level security. It enhances the utilization of wireless broadcast channel and creates a possibility for the practice of the public key cryptosystem in ubiquitous computing. All of the above papers address either technical issues in secure communication and ubiquitous computing systems or propose novel application models in the various aspects of ubiquitous services. They also trigger further related research and technology improvements in application and services of secure ubiquitous environments. Honorably, this special issue serves as a landmark source for education, information, and reference to professors, researchers, and graduate students interested in updating their knowledge about or active in techniques and novel application models for wireless and mobility services in ubiquitous systems. The guest editors would like to express their sincere gratitude to Prof. Mohammad S. Obaddat, Editor-in-Chief of the International Journal of Communication Systems (IJCS), for giving us the opportunity to prepare this special issue. In addition, we are deeply indebted to the numerous reviewers for their professional effort, insight, and hard work put into commenting on the selected articles which reflect the essence of this special issue. Last but not the least, we are grateful to all the authors for their contributions and for undertaking two-cycle revision of their manuscripts, without which this special section could not have been produced.