25 research outputs found

    A fuzzy-based reliaility for JXTA-overlay P2P platform considering data download speed, peer congestion situation, number of interaction and packet loss parameters

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    (c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.In this paper, we propose and evaluate a new fuzzy-based reliability system for Peer-to-Peer (P2P) communications in JXTA-Overlay platform considering as a new parameter the peer congestion situation. In our system, we considered four input parameters: Data Download Speed (DDS), Peer Congestion Situation (PCS), Number of Interactions (NI) and Packet Loss (PL) to decide the Peer Reliability (PR). We evaluate the proposed system by computer simulations. The simulation results have shown that the proposed system has a good performance and can choose reliable peers to connect in JXTA-Overlay platform.Peer ReviewedPostprint (author's final draft

    Hybrid algorithms for independent batch scheduling in grids

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    Grid computing has emerged as a wide area distributed paradigm for solving large-scale problems in science, engineering, etc. and is known as the family of eScience grid-enabled applications. Computing planning of incoming jobs efficiently with available machines in the grid system is the main requirement for optimised system performance. One version of the problem is that of independent batch scheduling, in which jobs are assumed to be independent and are scheduled in batches aimed at minimising the makespan and flowtime. Given the hardness of the problem, heuristics are used to find high quality solutions for practical purposes of designing efficient grid schedulers. Recently, considerable efforts were spent in implementing and evaluating not only stand-alone heuristics and meta-heuristics, but also their hybridisation into even higher level algorithms. In this paper, we present a study on the performance of two popular algorithms for the problem, namely Genetic Algorithms (GAs) and Tabu Search (TS) and two hybridisations involving them, namely, the GA (TS) and GA-TS, which differ in the way the main control and cooperation among GA and TS are implemented. The hierarchic and simultaneous optimisation modes are considered for the bi-objective scheduling problem. Evaluation is done using different grid scenarios generated by a grid simulator. The computational results showed that the hybrid algorithm outperforms both the GA and TS for the makespan parameter, but not for the flowtime parameter.Peer ReviewedPostprint (author's final draft

    A fuzzy-based reliability system for JXTA-overlay P2P platform considering as new parameter sustained communication time

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    (c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.In this paper, we propose and evaluate a new fuzzy-based reliability system for Peer-to-Peer (P2P) Communications in JXTA-Overlay platform considering as a new parameter the sustained communication time. In our system, we considered four input parameters: Data Download Speed (DDS), Local Score (LS), Number of Interactions (NI) and Sustained Communication Time (SCT) to decide the Peer Reliability (PR). We evaluate the proposed system by computer simulations. The simulation results have shown that the proposed system has a good performance and can choose reliable peers to connect in JXTA-Overlay platform.Peer ReviewedPostprint (author's final draft

    Effects of sustained communication time on reliability of JXTA-Overlay P2P platform: a comparison study for two fuzzy-based systems

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    (c) 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.In P2P systems, each peer has to obtain information of other peers and propagate the information to other peers through neighboring peers. Thus, it is important for each peer to have some number of neighbor peers. Moreover, it is more significant to discuss if each peer has reliable neighbor peers. In reality, each peer might be faulty or might send obsolete, even incorrect information to the other peers. We have implemented a P2P platform called JXTA-Orverlay, which defines a set of protocols that standardize how different devices may communicate and collaborate among them. JXTA-Overlay provides a set of basic functionalities, primitives, intended to be as complete as possible to satisfy the needs of most JXTA-based applications. In this paper, we present two fuzzy-based systems (called FPRS1 and FPRS2) to improve the reliability of JXTA-Overlay P2P platform. We make a comparison study between the fuzzy-based reliability systems. Comparing the complexity of FPRS1 and FPRS2, the FPRS2 is more complex than FPRS1. However, it considers also the sustained communication time which makes the platform more reliable.Peer ReviewedPostprint (author's final draft

    Advances in Network-Based Information Systems

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    Urban Regeneration of Underused Industrial Sites in Albania

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    Industrial heritage can be considered as a significant asset of modern civilization, mostly epitomizing living patrimony of industrialization process. However, it nowadays represents under-valuated heritage, as a consequence of massive closure of industrial sites due to political and economical changes through years. This thesis focuses on the study and recognition of underused Albanian industrial sites, mostly constructed during the communist period, and proposes possible regeneration model based on international examples. The majority of Albanian degraded sites, due to change of regime and mass closure or harassment of industrial sites, are being seen as high priority objective from central government and municipalities. At the verge of approval of General National Plan of the Republic of Albania and most of Local General Plans for country’s municipalities, it has become a primary requirement the redevelopment of these “silent” assets, which now have the opportunity to become promotors of cities development. The study follows with descriptive analysis of international positive cases, reflecting how these internventions can be appropriately applied for Albanian cases. Consistent reuse methodologies were proposed based on three pillars: economic and urban, environmental and heritage. Lastly, this thesis presents general conclusion for practical application of the above mentioned methodologies, as a positive approac

    Parameter Estimation for Propagation along Random Rough Surface by Using Line of Sight Data

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    Securing Cluster Head Selection in Wireless Sensor Networks

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    Wireless Sensor network routing protocols are prone to various attacks as these protocols mainly provide the function of routing data towards the sink. LEACH is a one of the routing protocol used for clustered implementation of wireless sensor network with Received Signal Strength based dynamic selection of Cluster Heads. But, as with other routing protocols, LEACH is also prone to HELLO flood attack when the malicious sensor node becomes the Cluster Head. Cryptographic and non-cryptographic approaches to detect the presence of HELLO flood attack also exist but they lack efficiency in some way. In this paper, an efficient protocol is proposed for the detection and prevention of HELLO Flood attack in wireless sensor network. Cluster heads are vulnerable to various malicious attacks and this greatly affects the performance of the wireless sensor network. Cryptographic approaches to prevent this attack are not so helpful though some non-cryptographic methods to detect the HELLO Flood attack also exist but they are not too efficient as they result in large test packet overhead. In this paper, we propose HRSRP (Hello flood attack Resistant Secure Routing Protocol) extension to LEACH protocol so as to protect the cluster head against Hello flood attack. HRSRP is base on encryption using Armstrong number and decryption using AES algorithm to verify the identity of cluster head. The proposed technique is implemented in NS2, the experimental results clearly indicate the proposed technique has significant capability for the detection of hello flood attack launched for making the malicious node as the cluster head

    Object-based Information Flow Control in Peer-to-peer Publish/Subscribe Systems

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    Distributed systems are getting so scalable like IoT (Internet of Things) and P2P (Peer-to-Peer) systems that millions of devices are connected and support various types of applications. Here, distributed systems are required to be secure in addition to increasing the performance, reliability, and availability and reducing the energy consumption. In distributed systems, information in objects flows to other objects by transactions reading and writing data in the objects. Here, some information of an object may illegally flow to a subject which is not allowed to get the information of the object. Especially, a leakage of sensitive information is to be prevented from occurring. In order to keep information systems secure, illegal information flow among objects has to be prevented. Types of synchronization protocols are so far discussed based on read and write access rights in the RBAC (Role-Based Access Control) model to prevent illegal information flow.In this thesis, we newly propose a P2PPSO (P2P type of topic-based PS (Publish/Subscribe) with Object concept) model and discuss the models and protocols for information flow control. A P2PPSO model is composed of peer processes (peers) which communicate with one another by publishing and subscribing event messages. Each peer can both publish and receive event messages with no centralized coordinator compared with traditional centralized PS models. Each event message published by a source peer carries information to a target peer. The contents carried by an event message are considered to be composed of objects. An object is a unit of data resource. Objects are characterized by topics, and each event message is also characterized by topics named publication topics.In order to make a P2PPSO system secure, we first newly propose a TBAC (Topic-Based Access Control) model. Here, an access right is a pair ⟨t, op⟩ of a topic t and a publish or subscribe operation op. A peer is allowed to publish an event message with publication topics and subscribe interesting topics only if the publication and subscription access rights are granted to the peer, respectively. Suppose an event message e_j published by a peer p_j carries an object on some topics into a target peer p_i. Here, information in the peer p_j illegally flows to the peer p_i if the target peer p_i is not allowed to subscribe the topics. An illegal object is an object whose topics a target peer is not allowed to subscribe. Even if an event message is received by a target peer by checking topics, objects carried by the event message may be illegal at the target peer. Hence, first, we propose a TOBS (Topics-of-Objects-Based Synchronization) protocol to prevent target peers from being delivered illegal objects in the P2PPSO system. Here, even if an event message is received by a target peer, illegal objects in the event message are not delivered to the target peer.In the TOBS protocol, every event message is assumed to be causally delivered to every common target peer in the underlying network. Suppose an event message e_2 is delivered to a target peer p_i before another event message e_1 while the event message e_1 causally precedes the event message e_2 (e_1 →_c e_2). Here, the event message e_2 is premature at the peer p_i. Hence, secondly, we propose a TOBSCO (TOBS with Causally Ordering delivery) protocol where the function to causally deliver every pair of event messages is added to the TOBS protocol. Here, we assume the underlying network supports reliable communication among every pair of peers, i.e. no event message loss, no duplicate message, and the sending order delivery of messages. Every pair of event messages received by using topics are causally delivered to every common target peer by using the vector of sequence numbers.In the TOBS and TOBSCO protocols, objects delivered to target peers are held as replicas of the objects by the target peers. If a peer updates data of an object, the peer distributes event messages, i.e. update event messages, to update every replica of the object obtained by other peers. If a peer updates an object without changing topics, the object is referred to as altered. Here, an update event message for the altered object is meaningless since peers check only topics to exchange event messages. Hence, thirdly, we propose an ETOBSCO (Efficient TOBSCO) protocol where update event messages of objects are published only if topics of the objects are updated to reduce the network overhead.In the evaluation, first, we show how many numbers of event messages and objects are prevented from being delivered to target peers in the TOBS protocol. Next, we show every pair of event messages are causally delivered but it takes longer to deliver event messages in the TOBSCO protocol than the TOBS protocol. Finally, we show the fewer number of event messages are delivered while it takes longer to update replicas of altered objects in the ETOBSCO protocol than the TOBSCO protocol.博士(工学)法政大学 (Hosei University

    Design and implementation of testbed using IoT and P2P technologies: improving reliability by a fuzzy-based approach

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    The internet of things (IoT) is a new type of internet application which enables the objects to be active participants with other members of the network. In P2P systems, each peer has to obtain information of other peers and propagate the information through neighbouring peers. However, in reality, each peer might be faulty or might send incorrect information. In our previous work, we implemented a P2P platform called JXTA-overlay, which provides a set of basic functionalities, primitives, intended to be as complete as possible to satisfy the needs of most JXTA-based applications. In this paper, we present the implementation of a testbed using IoT and P2P technologies. We also present two fuzzy-based systems (FPRS1 and FPRS2) to improve the reliability of the proposed approach. Comparing the complexity of FPRS1 and FPRS2, the FPRS2 is more complex than FPRS1. However, FPRS2 makes the platform more reliable.Peer ReviewedPostprint (author's final draft
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