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With the development of cloud computing, and as the basis of data services, security problems of cloud storage are growing more attention. Based on distributed storage, multi-domain and multi-tenant characteristics, combined with access control technologies, this paper sets up the Role-based Access Control using Ontology and domians in Cloud Storage (DOnto_RBAC), which could provide a concise and effective strategy for service providers (isps). According to the characteristics of access control in cloud storage, based on the standards (called CDMI), this paper adds Domains and Time constraints of roles into RBAC. With ontology technologies and the OWL language, this paper establishes ontology model including entities’ descriptions and strategies to realize reasoning of multi-domain access control permissions. We realized our system through Python and established Restful APIs. Experiments in campus-level cloud storage called Swift showed that, using requests with Restful format commands, DOnto_RBAC was proved to be effective to manage distributed and multi-domain data in cloud storage.

Replication technology, such as Quorum NRW system, is the most effective technology to improve availability of SaaS. However, the variety of SaaS transaction will result in application unbalance. In this paper, we construct a new Quorum NRW system for multi-tenant database which is based on the method of sharing database and schema model. It can provide different R and W values for each tenant according to application transaction features. The paper summarizes the left change and the right change modes according to the differences changes, and proposes Multi-tenant Quorum NRW system which transitive left change method and transitive right change method online. Multi-tenant Quorum NRW system can ensure strong consistency in condition of R + W> N. We design an experimental evaluation of multi-tenant Quorum NRW system, experimental data shows that Quorum NRW system enhances the transaction throughput by 5%-25%.

Encrypt message with strongly secure key which is known only by sending and recipient end is a significant aspect to acquire robust security in sensor network. The secure exchange of key between sender and receiver is too much difficult task in resource constraint sensor network. To achieve secure key agreement is challenging task for sensor network environment. The key management helps to maintain confidentiality of secret information from unauthorized users. It can also check the integrity of the exchanged message to verify the authenticity. This paper discusses various constraints available in sensor network, vulnerability through the existence of various security attacks at each layer for the communication and lastly the security requirement using the key management. Here we present the public key management using Elliptic Curve Cryptography to ensure robust security in sensor network environment.

Focusing on the problem that users would remove or delete the task at any time in cloud computing environment, a new scheduling algorithm for adapting to dynamic changes of user task is proposed. At first, the algorithm uses directed acyclic graph (DAG) to describe the association relation of cloud computing tasks. When a task needs to be removed, the algorithm utilizes a cost function to determine whether to cancel this task, and then updates the DAG according to its dependence on removed task. Finally, it uses a heuristic algorithm to perform scheduling. Experimental results show that this algorithm can better avoid scheduling execution of revoked tasks and improve the executive efficiency of cloud computing resource. Its performance is better than Min-Min and Max-Min in executive time span.

Clustering of Weibo users is one of the most important topics in data mining on social network. Clustering can help dig out the relations among people or between people and resources. A lot of work relating to clustering has been done on analyzing personal relationship, whereas we focus our clustering model on preferences and interests. In this article, we propose a new clustering model focusing on users’ tags people choose to describe themselves. First, we will study the characteristics of Sina Weibo tags of users, which are the foundation of the new clustering model. Second, we will use the word2vec tool to cluster Weibo users based on their tags and verify the accuracy of the results.

This paper deals with the modelling and control of a doubly-fed Induction generator (DFIG) based grid connected wind energy conversion system .Back to back Pulse width modulated insulated gate bipolar transistors(IGBT) based voltage source converters(VSC) have been used for the control. The complete mathematical analysis of stator flux oriented control and stator voltage oriented control of DFIG based wind system has been done. Maximum power tracking has been done through rotor speed control. The proposed electromechanical system is modelled and simulated in MATLAB using Simulink and Sim power system toolboxes. The performance of the system for both the control strategies is presented to demonstrate the difference between the two.

Recently, it has been more and more popular to build hybrid storage systems on the basis of SSD (Solid State Drives) and HDD (Hard Disk Drive). In order to evaluate the performance of various hybrid storage based algorithms, this paper proposes a flexible simulation tool called SH-Sim. SH-Sim aims to provide a flexible virtual hybrid disk which is made up of a virtual SSD and a virtual HDD. SH-Sim can run on the various types of SSDs and HDDs with different parameter configurations. SH-Sim not only simulates the hardware features of HDD and SSD, but also provides a virtual management layer for the algorithms to support the switching between algorithms. The experiment proves SH-Sim can simulate the hardware performance effectively and can support the running of various algorithms.

Cloud balancing provides an organization with the ability to distribute application requests across any number of application deployments located in different data centers and through Cloud-computing providers. In this paper, we propose a load balancing method- Minsd (Minimize standard deviation of Cloud load method) and apply it on three levels control: PEs (Processing Elements), Hosts and Data Centers. Simulations on CloudSim are used to check its performance and its influence on makespan, communication overhead and throughput. A true log of a cluster also is used to test our method. Results indicate that our method not only gives good Cloud balancing but also ensures reducing makespan and communication overhead and enhancing throughput of the whole the system.

Caching strategies and the resulting cache coherence control technique have become the key techniques for the system development. Based on the study of the cache technology of the home and abroad distributed file systems, and combined with the design requirements and characteristics for our multi-user parallel file system Cappella, this paper proposes a new meta-data cache management strategy. And this strategy not only improves the performance of metadata services, reducing the user access latency, but also controls metadata cache consistency very well.

In recent wireless communication has become more popular because of its flexibility. That is, there is no need of large and complex physical establishment; one can connect with it easily using radio waves. But on the other part it also increases the chance for the unauthorized users to misuse it as there are fewer burdens in connectivity as compared to wired communications. The unauthorized access is called intrusions. Denial-of-service attacks are simplest but dangerous attacks which send excessive amount of false packets in order to jam and congest the network traffic. A technique is proposed in order to detect those intrusions by analyzing the network traffic pattern against suspicious pattern.

The resource allocation is the basic guarantee for the effective implementation of the university development strategy, while resource allocation mechanism is an effective control measure to strengthen the university management. So the importance of resource allocation has caused widespread attention and concern of university administrators. Combining with the actual situations and encountered problems of university resource management, we introduced cloud computing ideas and proposed a cloud-computing-based resource allocation model to conduct a preliminary exploration and research on this issue. We first formulated the resource allocation problem, and then proposed the resource allocation concept model and its corresponding application model in universities. Based on the proposed model, we further expanded detailed analyses and descriptions on resource definition and description, resource allocation rules and methods, resource management mode, and a general mathematical model of resource allocation optimization in university. Finally, we gave a cloud-computing-based university resource allocation framework to offer references and consult for further applications of technology based on cloud computing in the university resource construction, aiming to achieve optimal university resource allocation and improve teaching quality and efficiency.

In cloud platforms, virtualization technology has been widely applied for deploying large-scale IT-infrastructures due to its flexibility and extendibility. However, the extra software layer introduced by virtualization technology also raises many performance issues. One of them is the energy-efficiency losses when massive I/O-intensive tasks are running on virtualized servers. In this paper, we present a novel virtual machine scheduling approach, which the scheduler allows virtual machines to obtain extra CPU shares if they were frequently blocked by I/O interrupted recently. In this way, I/O-intensive tasks will have more chances of being scheduled so as to compensate their performance losses caused by I/O operations. Extensive experiments are conducted by using various benchmarks, and the results show that the proposed policy outperforms existing scheduling algorithm in the term of energy-efficiency especially when the virtualized system is in presence of intensive mixed-workloads.

Control of PV-grid connected inverter introduces a delay between sinusoidal current reference and measured current at the output of the inverter. This leads to a phase difference between the current injected by the inverter and grid voltage when using a simple PI controller. To overcome this problem, PI controllers used to control injected currents to the grid have been substituted, in this study, by resonant controllers. The obtained results show that phase difference between grid current and voltage have been practically suppressed; hence power factor obtained is close to one.

Recent work shows sink mobility can improve the energy efficiency in wireless sensor networks. However, the mobile sink often leads to increasing the energy consumption and routing protocol variation, so support mobile sinks, energy efficient routing protocol is essential. In this light, the Minimum energy consumption relay node is proposed, which plays a import role to broadcasting the estimated sink’s location information to the nodes which take data packets to establish the efficient routing. Meanwhile the periodic broadcast scheme to provide the sink’s location information is broadcast to entire network in order to increase the data packet delivery ratio. The simulation and experiments show that the proposed routing algorithm reduces the energy consumption of the network node, and at the same time keep the network higher data rate.

Based on the distribution parameters equation of long-distance transmission lines, which is expressed in phasor form, the paper proposes a discretization equation model, analyzes the protection of EHV transmission lines with shunt reactors by applying power balance principle and then the power balance protection criterion is determined. The power balance protection method, which is based on discretization equation of long-distance transmission lines, maximizes the use of the fault information such as voltage and current, etc. In this way, the fault of EHV transmission lines with shunt reactors can be removed accurately and quickly. On the other hand, this method is more convenient for modern microprocessor protection to process the discrete data and improve the power system performance after the criterion of power balance protection is determined. Results of EMTP simulation have demonstrated that under various fault conditions of EHV transmission lines with shunt reactors the power balance protection method has higher sensitivity and reliability and can be applied to identify the internal or external fault correctly.

The privacy of the information against the cloud was assured by the technique of encryption and the usage of approaches of conventional encryption is not enough to hold up the access control policies of fine-grained organizational enforcement. Throughout the initial encryption and subsequent re-encryptions, scheme of two layer of encryption was developed that diminishes the overhead sustained by the owner. During the addition or removal of identity attributes the owner has no need to re-encrypt the data since the essential re-encryptions were performed by the cloud to implement the access control policies and consequently the two layer of encryption approach reduces the overhead of computation and communication at the owner. In the approach of two layer of encryption, the time of running at the cloud is superior to that at the owner in view of the fact that the cloud performs encryption of fine grained while the owner only carries out coarse grained encryption.

Information Network Communications Group has introduced virtual services to seize the market, the communication channel resources appear uneven conflict. Based on characteristics of complex systems provide virtual network services when the information network of the Group , with the structural model and Multi-Agent ontology descriptions , give full play to the advantages of multi- Agent system in distributed computing and collaboration, combined with the company features a modern organizational structure, analysis its public resources collaborative model of conflict resolution , the establishment of a public resource conflict resolution strategies based on dynamic compensation.

With the development of cloud computing, many organizations are deploying their IT infrastructures through cloud platforms so as to provide services for more and more users. Therefore, resource pricing mechanism becomes a key component in these open cloud platforms. In this paper, we propose a gaming theory based cloud resource pricing model, in which a cooperative gaming model is applied to optimize the resource benefits and non-cooperative gaming model is used to balance the user’s costs and provider’s benefits. Theoretical analysis is presented to validate the correctness of the proposed gaming model, and extensive experiments are conducted to investigate the effectiveness of the proposed resource pricing mechanism. The results indicate that our resource pricing mechanism outperforms many existing approaches in terms of resource profits and response time, especially when the cloud system is in presence of intensive workloads.

Cryptography is the technique which is utilized for secure communication over the network. By using Cryptography technique readable information is converted into an unreadable form. Cryptography is used to protect data from unauthorized access. Universality of security in modern internet based application is an explicit motivation to contribute in the area of Information Security. Multimedia data contain different types of data that include text, audio, video, graphic, images. This paper gives an initiation of an amending technique for multiple selective region image cryptography based on both RC4 stream cipher and chaos. This approach is derived from the standard RC4 algorithm. But Currently RC4 is vulnerable. So for making image encryption technique more secure, we have proposed RC4 with chaos. We have shown that, our proposed method will boost image security over any type of network with several types of attack.

With the widespread use of mobile smart device, and its ubiquitous network access capability, microblog have important influence. But to one node in microblog space, how to measure its importance is a key problem. In this paper, we propose a method to evaluate and compute the influence of one node in sina Weibo. An algorithm named MicroV is proposed to quantify the strength of one user in the microblog space. We use the algorithm to evaluate 60 thousand uses in the Sina Weibo.

Cloud computing integrates a large number of virtual resources and provides flexible service to users by pay-as-you-need. Compared with the traditional software systems, the fault detection is more complex and difficult in cloud computing systems. The fault model is helpful for people to find and distinguish the software fault. However, the current researches mostly focus on software fault model under the traditional environment. Based on the research of software fault model, this paper proposed the fault models in cloud computing systems combining with the characteristics of cloud computing. Then an improved C4.5 decision algorithm is used to distinguish the cloud fault. The experiment results showed that the fault model and improved algorithm is effective.

In Cloud Computing data security as well as load balancing of cloud server is very important and most challenging issues. Cloud reduces cost by providing on demand access of resources, it provides guaranteed, reliable services and dynamic allocation of resources. In cloud a single server stores very huge amount of data so there is need to balance load and provide fast transmission on cloud. Many users store their information on a single server, so there are chances of threats by unauthorized user. As we know on cloud we don’t have control over our data so security is a very important and challenging issue for cloud. If any algorithm provides fast transmission between user and server then there would be minimum chances for congestion and the data spend minimum time on transmission channel so it will give minimum time to attack on their data. In this paper, I proposed an ides and try to implement an algorithm through which cloud service provider can give the control to user itself. This algorithm uses a key and that key should be unknown from unauthorized person, the key may be user’s password or any secret information then this algorithm will give control to user and provide better security for user’s data where user would be free from authentication, correctness integrity or confidentiality. It is very important to .give control on user’s hand for reliability of services. Keywords:

Trusted computing is one of the most important technologies to ensure the information security of smart grid. Remote attestation can guarantee the trusted access of interactive terminals of smart grid (SGIT).The existing remote attestation schemes have the following disadvantages: ① The verifier initiates authentication request, and the attestor returns the platform configuration information. This pattern is not suitable for smart grid application environment. ② There is a man in the middle attack, impersonation attack and platform configuration eavesdropping risk, and so on. In view of the above defects, this paper proposes a remote attestation model sponsored by attestor which is based on the binary certificate and combined with the practical application environment. Also, the remote attestation protocol is designed, and the performance and characteristics of the protocol is analyzed.Analysis of the protocol was made. The results suggest that this protocol can make sure the credible access of SGIT and has practical application value.

As more and more organizations publish their data or services through Open APIs on the Internet, mashup applications have captured a lot of attention in recent years. However, as the number and categories of Open APIs grow rapidly, efficiently creating optimal mashup applications becomes a crucial issue for making the technology of mashup more applicable. In this work, we present a Mashup Directed Orchestration Model (MDOM) to depict the mashup patterns with a graph-based model on the basis of mashup orientation. According to the features of MDOM, by taking advantage of the theory of directed graph and the strategies used in the algorithms for discovering frequent sub-graphs, an algorithm named as FSOMM is presented to efficiently mine the frequent orchestration patterns hidden in the MDOMs. These discovered frequent orchestration patterns provide us a promising way to create optimal mashup applications. In addition, the performance of the proposed approach is verified by implementing a series of experiments on both synthetic and real datasets.

Wireless Sensor Network (WSN) is composed of large number of sensor nodes which communicate with each other through wireless medium. Such networks are prone to the attack of self-replicating worms known as malware used to bring different form of attacks on the WSN during the communication of the sensor nodes. Efficient countermeasures to anticipate malware hazards are to be developed and understand the threats they pose before they emerge in the hands of the attackers. In this paper, we propose security mechanisms using three different epidemic models with proper countermeasure which depends on the incidence of worm infections. A special crashed compartment is introduced that includes the nodes which crash out due to induced infection or reason other than the attack. The crashed class is expected to provide a new view-point which can help in optimizing the level of infection and of corresponding recovery of sensor nodes in the wireless sensor network. The past and present information of the worms represented in the form of Information variable and a Control function to minimize the attack of malware in WSN is taken into account in the different epidemic models developed. Further threshold values have been obtained that determine whether the worms completely die out or not. The stability of the worms-free and endemic equilibrium of the epidemic models is well discussed and it is also shown that the models may undergo a forward bifurcation. To validate the models extensive simulation is carried out. The results may help in developing a proper secure mechanism in WSN.

When the ultra high voltage (UHV) substation used the gas insulated switchgear (GIS) system to switch lines with capacitive current, the pre-breakdown and multiple reignition will occur between switching contacts. Because of discharge characteristics of SF6 and special structures of GIS system, the variations of the electromagnetic transient process and very fast transient overvoltage (VFTO) are very fast and extremely complex. The development process and characteristics of VFTO remain to be dealt with to seek effective suppression measures. The overvoltage of closing no-load long lines on GIS system is analyzed in detail. The simulation model of the very fast transient process of closing no-load long lines on UHV GIS system is established. The VFTO of closing no-load China UHV transmission demonstration project Jindongnan-Nanyang-Jingmen 1000 kV transmission lines is analyzed using electromagnetic transient simulation software ATP-EMTP. The VFTO of closing no-load long lines on UHV GIS system is simulated and calculated, when the system has no additional closing resistors and lightning arresters, additional single stage closing resistors, additional multistage closing resistors, lightning arresters in two terminals of lines, lightning arresters in two terminals and the middle of lines, and additional multistage closing resistors and lightning arresters in two terminals and the middle of lines. The simulation results show that the additional multistage closing resistors and lightning arresters in two terminals and the middle of lines can effectively restrain the VFTO of closing no-load long lines on UHV GIS system.

It becomes more and more important to design high-speed parallel cryptographic algorithms due to a growing need for information security. Conic curves cryptography is a new developing direction in the field of information security in recent years and there are less works focused on the parallel encryption algorithms for conic curves crypto system. This paper proposes four parallel algorithms for conic curves cryptosystem over finite field GF(2n). One parallel algorithm of modular-multiplication is designed by analyzing its data dependency and making some modifications of several steps. In order to figure out the average runtime, we consider the probability distributions of different cases to compute the mathematical expectation. The operations of point-addition, point-double and point-multiplication, three fundamental point operations in conic curves cryptosystem over finite field GF(2n), are paralleled based on this parallel algorithm of modular-multiplication and two parallel algorithms we proposed before. Time complexities and speedup ratios of the parallel algorithms and the sequential algorithms are calculated to make the quantitative comparison. The performance evaluation shows better efficiencies of the proposed parallel algorithms compared to the traditional algorithms.