Peer-to-Peer Networking and Applications

Effectively resource management in the cloud environment can improve the utilization of resource and reduce resource costs and overheads.Task scheduling and optimization within the cloud computing environment are one of the main concerns that need to be handled to increase resource utilization and QoS (Quality of Service). Although there are some algorithms have been proposed to handle the problem of task scheduling, existing methods mainly focus on reducing the task execution time while ignoring the other factors such as workload balance and QoS. In this paper, we put forward a novel algorithm named ITSA (Improved Task Schedule Algorithm), which is based on the gain value of task swap and performs “task pair” scheduling by utilizing the greedy strategy. The main idea of ITSA can be concluded as follows: Firstly, we present the concept of the gain value of task swap; then, we bind task with the minimum gain value and task with the maximum gain value together to form a “task pair”, and perform scheduling by adopting the greedy strategy. Finally, we evaluate the proposed algorithm by extensive experiment, and the data obtained from the experiment shows that the proposed algorithm has a better performance compared with other algorithms in terms of the workload balance and QoS.

Industrial safety refers to the prevention of industrial accidents by limiting the factors that cause them. In other words, it encompasses all the activities required to safeguard and maintain industrial facilities and protect workers from all health issues caused by the disasters or accidents incurred by industrial activities. However, inadequate industrial safety education, a lack of preventative systems, and a lack of predictive facilities have led to frequent industrial accidents. These industrial accidents increase economic losses and lead to an increase also in the number of workers’ deaths and injuries. The objective of the study presented in this paper was therefore to develop a disaster prevention system to ensure the safety of workers in extreme industrial fields. In the system, peer-to-peer (P2P) sensor network technology is applied to allow the status of the worksite to be monitored in real time by the general management center, field manager, and workers in the industrial field. For the system, we developed a smartphone application that transmits the results of a harmful gas detection module and a workplace escape map, and designed a structure that connects the management center and field workers through a wireless communication repeater. In addition, we propose an integrated system that collects disaster information in real time through the P2P sensor network system. In the future, when disasters occur, the person in charge and the manager will be able to transmit information in real time, which will all owa rapid response to situations.

Mobile Ad-Hoc NETworks (MANETs) are highly vulnerable to various security threats due to the numerous constraints they present, such as the absence of a fixed infrastructure, the dynamic topology change, their dependence on cooperative communication, the limited resource constraints, the unreliability of wireless links, and most importantly the lack of a clear line of defence. In this paper, MANET security issues are addressed through a comprehensive analysis of some common security threats, mainly blackhole, grayhole and the selfish behaviour attack. This has led to the building of a new intrusion response system denoted MASID-R-SA. This system is capable of providing autonomic systematic responses based on the intrusions’ measured severity level. The main objective of this approach is to better survive both single and multiple intrusion scenarios while minimizing the negative consequences of adopting typical static responses. We demonstrate through simulations the effectiveness of the proposed intrusion response system in appropriately responding to both single and multiple intrusions. For instance, a true detection rate of 97,23% and an average of 96,33% response success rate are achieved. The study revealed, also, that the proposed system solves some critical issues related to network partitioning and remerging efficiently.

Session Initiation Protocol (SIP) has proved to be the integral part and parcel of any multimedia based application or IP-based telephony service that requires signaling. SIP supports HTTP digest based authentication, and is responsible for creating, maintaining and terminating sessions. To guarantee secure SIP based communication, a number of authentication schemes are proposed, typically most of these are based on smart card due to its temper resistance property. Recently Zhang et al. presented an authenticated key agreement scheme for SIP based on elliptic curve cryptography. However Tu et al. (Peer to Peer Netw. Appl 1–8, 2014) finds their scheme to be insecure against user impersonation attack, furthermore they presented an improved scheme and claimed it to be secure against all known attacks. Very recently Farash (Peer to Peer Netw. Appl 1–10, 2014) points out that Tu et al.’s scheme is vulnerable to server impersonation attack, Farash also proposed an improvement on Tu et al.’s scheme. However, our analysis in this paper shows that Tu et al.’s scheme is insecure against server impersonation attack. Further both Tu et al.’s scheme and Farash’s improvement do not protect user’s privacy and are vulnerable to replay and denial of services attacks. In order to cope with these limitations, we have proposed a privacy preserving improved authentication scheme based on ECC. The proposed scheme provides mutual authentication as well as resists all known attacks as mentioned by Tu et al. and Farash.

With the increasingly prominent problem of data security in Narrowband Internet of Things (NB-IoT) terminal transmission, the existing cryptographic algorithms still have problems that cannot meet the security requirements of Narrowband Internet of Things terminal data and the low degree of lightweight. A lightweight block cryptographic algorithm SPNRX based on variant And-Rotate-XOR (ARX) structure and Substitute Permutation Network (SPN) structure is proposed. The proposed algorithm takes into account the unique security requirements of the NB-IoT terminal, such as simplifying the encryption process as far as possible, not too long encrypted data and high-security level, and reducing the number of encryption rounds. It overcomes the shortcoming that half of the block information of the ARX structure does not change during one round of encryption, to improve the diffusion speed. In addition, considering the security of keys and the cost of hardware implementation, a key schedule based on matrix transformation and P-box permutation is proposed. The security analysis of the SPNRX shows that the SPNRX is resistant to differential analysis, linear analysis, etc. Finally, the hardware and software performance of the SPNRX is tested. The experimental results show that the hardware implementation cost of the proposed algorithm is low; only 1357 GEs based on a 0.13 micron ASIC process are required. And the software implementation of the proposed algorithm performs well. Encryption and decryption of the proposed algorithm on the 64-bit processor take about 0.7748 ms and 0.7957 ms. And it requires 35.98 MB of memory resources. In addition, the algorithm's security strength and encryption effect are tested through key sensitivity, information entropy, etc. The results show that the proposed algorithm has high enough security.

The proliferation of large-scale Peer-to-Peer (P2P) Video on Demand (VoD) overlays has created the demands to characterize and to understand the emergent properties of P2P VoD applications. In this paper, we investigate the P2P VoD overlay network, spanned by PPLive application, using active measurements. We have developed a piece of measurement software, named as VoDCrawler, to implement the experiment. Different from other existing work, our study focuses on the topology and the churn of the overlay networks. From the study, we have revealed the major features of the P2P VoD overlay networks and have compared them with those in P2P file sharing and live streaming systems. The discoveries we have obtained could help further investigation of the operation of the P2P VoD systems and favor the commercial developments of the P2P VoD applications.