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The increase of demand for mobile data services requires a massive network densification. A cost-effective solution to this problem is to reduce cell size by deploying a low-cost all-wireless Network of Small Cells (NoS). These hyper-dense deployments create a wireless mesh backhaul among Small Cells (SCs) to transport control and data plane traffic. The semi-planned nature of SCs can often lead to dynamic wireless mesh backhaul topologies. This paper presents a self-organized backpressure routing scheme for dynamic SC deployments (BS) that combines queue backlog and geographic information to route traffic in dynamic NoS deployments. BS aims at relieving network congestion, while having a low routing stretch (i.e., the ratio of the hop count of the selected paths to that of the shortest path). Evaluation results show that, under uncongested conditions, BS shows similar performance to that of an Idealized Shortest PAth routing protocol (ISPA), while outperforming Greedy Perimeter Stateless Routing (GPSR), a state of the art geographic routing scheme. Under more severe traffic conditions, BS outperforms both GPSR and ISPA in terms of average latency by up to a 85% and 70%, respectively. We conducted ns-3 simulations in a wide range of sparse NoS deployments and workloads to support these performance claims. [ABSTRACT FROM AUTHOR]

Cloud computing is an emerging paradigm that affects a large part of the IT industry by offering dynamically scalable resources (e.g., hardware and software) that are provisioned as a service over the Internet. Cloud computing provides numerous advantages to organizations in terms of improved scalability, lower cost, and flexibility, to name a few. Despite these technical and economical advantages, many potential cloud consumers are still hesitant to adopt cloud computing due to security and privacy concerns. In particular, one of the main factors for the reluctance of organizations to adopt cloud computing is the lack of strong encryption scheme that can ensure the confidentiality of client's data while store in cloud service provider's (CSPs) data centers. With the existing encryption schemes adopted by the CSPs, there is always a possibility that the client's data can be compromised due to insider threats. In this paper, we propose a new scheme capable to secure client information from both insider and outsider threats. In particular, we develop an encryption scheme by combining both symmetric and asymmetric cryptographic algorithms, which provide strong data confidentiality preserving secret key encryption functionalities, including periodically renewable public key certificates through trusted third parties. Due to these functionalities, the data owner can utilize the best secret key encryption schemes while the trusted third party will hold and communicate the secret keys to CSPs on behalf of cloud service users (CSUs). [ABSTRACT FROM AUTHOR]

We propose a high throughput dissemination scheme for Vehicular Ad Hoc Networks (VANET) based on the dynamic formation of a multi-hop backbone network. We describe and analyze such a networking protocol when used to broadcast message flows generated by a Road Side Unit along a linear road, forming a VANET structure that is identified as a Vehicular Backbone Network (VBN). The VBN is based on elected vehicles that reside at preferred locations to act as backbone relay nodes, jointly optimally configured to operate at designated link data rates and spatial reuse factors. We present both an analytical evaluation of the broadcast throughput capacity that can be achieved by using the VBN mechanism and a simulative analysis based on the IEEE 802.11p CSMA/CA MAC protocol, standardized for VANET. The results demonstrate the significant performance enhancement achieved under VBN in attaining enhanced throughput capacity rate and in providing for a wider dissemination coverage span. Admitted packets are assured low end-to-end packet delays through the employment of a flow control scheme. [ABSTRACT FROM AUTHOR]

Research information, i.e., data about research projects, organisations, researchers or research outputs such as publications or patents, is spread across the web, usually residing in institutional and personal web pages or in semi-open databases and information systems. While there exists a wealth of unstructured information, structured data is limited and often exposed following proprietary or less-established schemas and interfaces. Therefore, a holistic and consistent view on research information across organisational and national boundaries is not feasible. On the other hand, web crawling and information extraction techniques have matured throughout the last decade, allowing for automated approaches of harvesting, extracting and consolidating research information into a more coherent knowledge graph. In this work, we give an overview of the current state of the art in research information sharing on the web and present initial ideas towards a more holistic approach for boot-strapping research information from available web sources. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we address an aspect of the mutual influence between the PHY layer budding blocks (FEC Blocks) and the MAC level allocations in the Uplink and Downlink of IEEE 802.16e/WiMAX networks. In these networks it is possible to transmit MAC level frames, denoted MAC PDUs, such that a PDU contains an integral number of fixed size Data Blocks. PDUs are transmitted over PHY Bursts, which are divided into FEC Blocks. We suggest several algorithms to compute the best way to define PDUs in a Burst in order to maximize several performance criteria. We also give guidelines on how to choose the best Modulation/Coding Scheme (MCS) to use in the Burst, given the SNR of the channel and the performance criteria. [Copyright &y& Elsevier]

Abstract: Reputation models play an important role in defending Ad-hoc networks, such as securing routing and data forwarding protocols, against insider attacks. However, the performance of reputation models could be easily compromised by various dishonest recommendation attacks, i.e., slandering, self-promoting and collusion. Mitigating the influence of dishonest recommendation remains an important and challenging issue in Ad-hoc networks, especially when the dishonest recommendations are in the majority. In this paper, we propose a simple, novel and effective recommendation verifying scheme (RecommVerifier) to deal with dishonest recommendation. In RecommVerifier, tackling dishonest recommendation problem is modeled as the trials in reputation management court. Then three collaborated parts including deviation detection, time verifying and proof verifying, are proposed to protect reputation model from not only individual dishonest recommendation attacks but also collective ones. The novelty of our proposal is that it does not merely depend on majority rule but introduces time verifying mechanism to reduce the false positives and false negatives caused by deviation detection. Furthermore, proof verifying mechanism, which works at the side of evaluated node, is proposed to verify whether the recommenders are honest with certainty. Experimental results show that the proposed scheme is both effective and lightweight in alleviating the influence of different types of dishonest recommendation attacks. [Copyright &y& Elsevier]

Abstract: Instance based matching is the process of comparing data from different heterogeneous data sources in determining the correspondence of schema elements. It is a useful alternative choice when schema information (element name, description, constraint) is unavailable or unable to determine the match between schema elements. Instance based matching is a non trivial problem and is applied in many application areas such as data integration, data cleaning, query mediations, and warehousing. Many instance based solutions to the schema matching problem have been proposed and most of them utilized similarity metrics. In this paper, we present a fully automatic approach that contributes to the solution of instance based matching in identifying the correspondences of attributes which is one of the elements in the schema by utilizing regular expression. Several experiments using real-world data set have been conducted to evaluate the performance of our proposed approach. The results showed that our proposed approach achieved better accuracy compared to previous approaches using similarity metrics. [Copyright &y& Elsevier]

Abstract: Multicast source authentication is a burning issues in multicast communication because multicast technology provide the better communication than unicast and broadcast. But its design architecture any member can send the data to all joined receivers due to publicly available IP address of group manager. To solve this hottest problems, several schemes have been existed in this category such as simple hash chaining, tree hash chaining where the attacker intensity are unchanged. In this paper, we are going to propose a improved mechanism for multicast source authentication which adapts the security level deployed based on threshold value of attack success rate. The results shows that propose approach dynamic security mechanism in multicast at minimum communication and computation overhead [Copyright &y& Elsevier]