Pub. online:1 Jan 2017Type:Research ArticleOpen Access
Journal:Informatica
Volume 28, Issue 1 (2017), pp. 193–214
Abstract
To provide better overall performance, identity (ID)-based signcryption (IBSC) has been constructed by combining ID-based signature (IBS) and ID-based encryption (IBE) in a secure manner. Undoubtedly, the IBSC fulfills the authentication and the confidentiality by signature and encryption, respectively. All the previously proposed IBSC schemes are inseparable in the sense that the two-layer sign-then-encrypt procedure must be performed only by the same entity. However, the entities, such as wireless sensors and smart cards, are resource-constrained and become time consuming in executing the two-layer sign-then-encrypt procedure. Nowadays, the usage of mobile cloud computing is gaining expanding interest which provides scalable and virtualized services over the Internet or wireless networks while users with resource-constrained devices can enjoy the advantages of mobile cloud computing environments. Hence, we aim to reduce the computational cost for resource-constrained devices by employing a third party. In this article, we present the first separable ID-based signcryption (SIBSC) scheme in which the signing and encrypting layers are performed by the device and a third party, respectively. Under the computation Diffie–Hellman (CDH) and bilinear Diffie–Hellman (BDH) assumptions, we demonstrate that the proposed SIBSC scheme offers the provable security of authentication and confidentiality while retaining communication performance.
Journal:Informatica
Volume 26, Issue 1 (2015), pp. 159–180
Abstract
Abstract
Traditional researches on scheduling of cloud workflow applications were mainly focused on time and cost. However, security and reliability have become the key factors of cloud workflow scheduling. Taking time, cost, security and reliability into account, we present a trust-based scheduling strategy. We firstly formulate the cloud workflow scheduling and then propose the corresponding algorithm, in which the trustful computation service and storage service are selected according to the set-based particle swarm optimization (S-PSO) method and set covering problem (SCP) tree search heuristic method, respectively. Finally, experimental results show that, compared with traditional methods, the proposed algorithm has better performance.
Journal:Informatica
Volume 24, Issue 3 (2013), pp. 381–394
Abstract
While users increasingly use such large multimedia data, more people use the cloud computing technology. It is necessary to manage large data in an efficient way, and to consider transmission efficiency for multimedia data of different quality. To this end, an important thing is to ensure efficient distribution of important resources (CPU, network and storage) which constitute cloud computing, and variable distribution algorithms are required therefor. This study proposes a method of designing a scheme for applying MapReduce of the FP-Growth algorithm which is one of data mining methods based on the Hadoop platform at the stage of IaaS (Infrastructure As a Service) including CPU, networking and storages. The method is then for allocating resources with the scheme.
Journal:Informatica
Volume 24, Issue 3 (2013), pp. 357–380
Abstract
This study proposes a model for supporting the decision making process of the cloud policy for the deployment of virtual machines in cloud environments. We explore two configurations, the static case in which virtual machines are generated according to the cloud orchestration, and the dynamic case in which virtual machines are reactively adapted according to the job submissions, using migration, for optimizing performance time metrics. We integrate both solutions in the same simulator for measuring the performance of various combinations of virtual machines, jobs and hosts in terms of the average execution and total simulation time. We conclude that the dynamic configuration is prosperus as it offers optimized job execution performance.
Journal:Informatica
Volume 19, Issue 4 (2008), pp. 517–534
Abstract
In this paper, we present a novel fine-grained access control system for applications where the information flow is critical; the confidentiality of the data is essential and there are a huge number of users who access different portions of an XML document as in military applications. We combine MAC and RBACK models for XML for use in the mentioned type of applications. In accordance with the peculiarities of the target applications, the access control model is structured in such a way that the implementation can be done efficiently for large number of users. In the system presented, instead of using access control lists, we use a security labeling approach in defining the grant rules. By combining the advantages of role-based and mandatory access control schemes, the access control system presented provides a fine-grained, flexible and effective access for applications where the confidentiality of data is crucial. The system is implemented and tested for correctness. Performance analysis is also given.