The healthcare sector is constantly improving patient health record systems. However, these systems face a significant challenge when confronted with patient health record (PHR) data due to its sensitivity. In addition, patient’s data is... more
The healthcare sector is constantly improving patient health record systems. However, these systems face a significant challenge when confronted with patient health record (PHR) data due to its sensitivity. In addition, patient’s data is stored and spread generally across various healthcare facilities and among providers. This arrangement of distributed data becomes problematic whenever patients want to access their health records and then share them with their care provider, which yields a lack of interoperability among various healthcare systems. Moreover, most patient health record systems adopt a centralized management structure and deploy PHRs to the cloud, which raises privacy concerns when sharing patient information over a network. Therefore, it is vital to design a framework that considers patient privacy and data security when sharing sensitive information with healthcare facilities and providers. This paper proposes a blockchain framework for secured patient health records sharing that allows patients to have full access and control over their health records. With this novel approach, our framework applies the Ethereum blockchain smart contracts, the Inter-Planetary File System (IPFS) as an off-chain storage system, and the NuCypher protocol, which functions as key management and blockchain-based proxy re-encryption to create a secured on-demand patient health records sharing system effectively. Results show that the proposed framework is more secure than other schemes, and the PHRs will not be accessible to unauthorized providers or users. In addition, all encrypted data will only be accessible to and readable by verified entities set by the patient.
Insider threats result from legitimate users abusing their privileges, causing tremendous damage or losses. Malicious insiders can be the main threats to an organization. This paper presents an anomaly detection system for detecting... more
Insider threats result from legitimate users abusing their privileges, causing tremendous damage or losses. Malicious insiders can be the main threats to an organization. This paper presents an anomaly detection system for detecting insider threat activities in an organization using an ensemble that consists of negative selection algorithms (NSA). The proposed system classifies a selected user activity into either of two classes: "normal" or "malicious." The effectiveness of our proposed detection system is evaluated using case studies from the computer emergency response team (CERT) synthetic insider threat dataset. Our results show that the proposed method is very effective in detecting insider threats.
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In the last few years research activity in delay/disruption tolerant networks (DTN) is growing and researchers have proposed various types of routing protocols. Those efforts formulate DTN to become the adequate solution for the... more
In the last few years research activity in delay/disruption tolerant networks (DTN) is growing and researchers have proposed various types of routing protocols. Those efforts formulate DTN to become the adequate solution for the challenged network environment. DTN architecture provides good performance in the intermittently connected Mobile ad hoc networks (MANET). Routing in DTN architecture is the key challenge because of the nature of MANET environment where the network is an opportunistic connected and topology is changing rapidly. In this article we analyze the performance of DTN-based routing protocols including our routing approach, History of Encounters Probabilistic Routing Algorithm (HEPRA) in terms of different aspects. We select well-known DTN routing protocols in our evaluation to demonstrate how those protocols act comparing to our approach, HEPRA. We continue developing our algorithm, HEPRA, to provide a detailed analytical as well as simulation-based study. Using sim...
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There are many different factors in the physical layer that impact the performance evaluation of the routing protocols. Such factors consist of signal reception, path loss, fading and interference. With this in mind, a numerical approach... more
There are many different factors in the physical layer that impact the performance evaluation of the routing protocols. Such factors consist of signal reception, path loss, fading and interference. With this in mind, a numerical approach based on Finite State Markov Chain channel model was adopted for this study in order to evaluate the performance of an ad hoc routing protocol under various radio propagation models. In this paper, the authors present a new crosslayer algorithm for joint physical and routing layers in wireless ad hoc networks by applying this to the Optimized Link State Routing (OLSR) protocol in order to demonstrate the effectiveness of the Link Lifetime (LLT) and channel quality measured by Signal to Interference and Noise Ratio (SINR) as a metric in the selection of routes. The problem of link and route stability, focusing primarily on the multipoint relay (MPR) selection method, was addressed in order to find the most optimal routes between any pair of nodes. Th...
The extreme bandwidth and performance of 5G mobile networks changes the way we develop and utilize digital services. Within a few years, 5G will not only touch technology and applications, but dramatically change the economy, our society... more
The extreme bandwidth and performance of 5G mobile networks changes the way we develop and utilize digital services. Within a few years, 5G will not only touch technology and applications, but dramatically change the economy, our society and individual life. One of the emerging technologies that enables the evolution to 5G by bringing cloud capabilities near to the end users is Edge Computing or also known as Multi-Access Edge Computing (MEC) that will become pertinent towards the evolution of 5G. This evolution also entails growth in the threat landscape and increase privacy in concerns at different application areas, hence security and privacy plays a central role in the evolution towards 5G. Since MEC application instantiated in the virtualized infrastructure, in this paper we present a distributed application that aims to constantly introspect multiple virtual machines (VMs) in order to detect malicious activities based on their anomalous behavior. Once suspicious processes dete...
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In this research, we introduce middleware routing algorithms components for Mobile Ad-hoc Networks (MANETs). Unlike the conventional networks, MANET is a decentralized radio wireless network that can be established in situation where no... more
In this research, we introduce middleware routing algorithms components for Mobile Ad-hoc Networks (MANETs). Unlike the conventional networks, MANET is a decentralized radio wireless network that can be established in situation where no infrastructure exists or where deployment of infrastructure is expensive or inconvenient. This inherent flexibility makes it attractive for applications such as military operations, vehicle to vehicle networks, sensor networks, etc. Hence, MANETs require special type of routing algorithms to operate efficiently in such dynamic environment (i.e., wireless channel, bandwidth constrains, nodes resources, etc …). In this thesis, we propose an add-on generic solution to on-demand ad-hoc routing protocols to enhance the routing protocols performance with minimum control overhead. Our Solution, namely, Destination Assisted Routing Enhancement (DARE), is based on the new idea of transmitting frequent destination beacon packets. These beacon packets are able to refresh the routing cache tables and announce the destination node existence. This methodology results in dramatically minimizing the initialization (learning/optimization) connection set-time as well as the network overhead. Comparison between the traditional Dynamic Source Routing protocol (DSR) and the DSR with DARE (DSR-DARE) are presented to show the potential of DARE middleware. Second, we propose middleware protocol components in order to improve the real-time applications at the receivers’ side; we propose an algorithm that gives the receiver dynamic ability to move from one multicast session to another based on the receiver capabilities and the path conditions leading to it. Our Multicast Multi-Stream (MMS) solution is added as an extension to the traditional Protocol Independent Multicast (PIM) protocol. Then, we present cooperative video caching technique in MANETs in order to reduce the average access latency as well as enhance the video accessibility. Efficient video caching placement and replacement strategies are developed at some of the distributed intermediate nodes across the network. The simulations results have shown that the system has better video perception (i.e. Quality of Service).
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Network resource measurement is a challenge for packet switched networks. Currently, many applications, such as video conferencing and streaming audio, require a guaranteed Quality of Service (QoS) to work properly. Ensuring minimum QoS... more
Network resource measurement is a challenge for packet switched networks. Currently, many applications, such as video conferencing and streaming audio, require a guaranteed Quality of Service (QoS) to work properly. Ensuring minimum QoS to traffic flows and groups of flows become an important challenge to network designers. In such an environment, resource measurement algorithms are utilized to ensure that admittance of a new flow into a resource constrained network does not violate the service level agreements guaranteed by the network to admitted flows and at the same time to achieve high network utilization. There has been extensive research on network resource measurement techniques. One category is active probing where probing packets are injected into network to measure network resource, such as bottleneck link bandwidth, available bandwidth. In this presentation, we show how to extend unicast resource measurement techniques to multicast environment to estimate bottleneck link...
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In the paper, experimental results are presented for both passive and active overhead infrared systems to detect and monitor vehicular road traffic. Both systems make use of computerized signal processing and correlation techniques to... more
In the paper, experimental results are presented for both passive and active overhead infrared systems to detect and monitor vehicular road traffic. Both systems make use of computerized signal processing and correlation techniques to determine presence of vehicles, traffic volume, vehicle speed measurement and length classification. The comparative advantages of both systems are discussed and their potential for integration in intelligent vehicle highway systems (IVHS) are examined.
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One of the effective ways of detecting malicious traffic in computer networks is intrusion detection systems (IDS). Though IDS identify malicious activities in a network, it might be difficult to detect distributed or coordinated attacks... more
One of the effective ways of detecting malicious traffic in computer networks is intrusion detection systems (IDS). Though IDS identify malicious activities in a network, it might be difficult to detect distributed or coordinated attacks because they only have single vantage point. To combat this problem, cooperative intrusion detection system was proposed. In this detection system, nodes exchange attack features or signatures with a view of detecting an attack that has previously been detected by one of the other nodes in the system. Exchanging of attack features is necessary because a zero-day attacks (attacks without known signature) experienced in different locations are not the same. Although this solution enhanced the ability of a single IDS to respond to attacks that have been previously identified by cooperating nodes, malicious activities such as fake data injection, data manipulation or deletion and data consistency are problems threatening this approach. In this paper, we propose a solution that leverages blockchain's distributive technology, tamper-proof ability and data immutability to detect and prevent malicious activities and solve data consistency problems facing cooperative intrusion detection. Focusing on extraction, storage and distribution stages of cooperative intrusion detection, we develop a blockchain-based solution that securely extracts features or signatures, adds extra verification step, makes storage of these signatures and features distributive and data sharing secured. Performance evaluation of the system with respect to its response time and resistance to the features/signatures injection is presented. The result shows that the proposed solution prevents stored attack features or signature against malicious data injection, manipulation or deletion and has low latency.
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The increase in the bandwidth of wireless channels and the computing power of mobile devices increase the interest in video communications over ad hoc wireless networks. However, the high error rate and the rapidly changing quality of the... more
The increase in the bandwidth of wireless channels and the computing power of mobile devices increase the interest in video communications over ad hoc wireless networks. However, the high error rate and the rapidly changing quality of the radio channels can be devastating for ...
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... 1215 Jefferson Davis Highway. ... Leave blank) 2. REPORT DATE June 1992 REPORT TYPE AND DATES COVERED Final Report TITLE AND SUBTITLE Transmission Techniques Tactical Switched Network Services 6. AUTHOR(S) Donald L. Schilling, PH.D.... more
... 1215 Jefferson Davis Highway. ... Leave blank) 2. REPORT DATE June 1992 REPORT TYPE AND DATES COVERED Final Report TITLE AND SUBTITLE Transmission Techniques Tactical Switched Network Services 6. AUTHOR(S) Donald L. Schilling, PH.D. Tarek Saadawi, PH ...
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The authors present a continuous-time Markov chain model for a single-hop network using the unslotted Aloha scheme. Two interconnected networks using the unslotted Aloha scheme have also been modeled, assuming that the gateway has a... more
The authors present a continuous-time Markov chain model for a single-hop network using the unslotted Aloha scheme. Two interconnected networks using the unslotted Aloha scheme have also been modeled, assuming that the gateway has a finite buffer. The mathematical model derived from the unslotted Aloha system is a special case of the model developed by R.R. Roy and T.N. Saadawi
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Google, Inc. (search). ...
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This paper introduces a transport layer solution for bandwidth aggregation, based on extending Stream Control Transmission Protocol (SCTP). The extended SCTP, which we refer to as Load-Sharing SCTP (LS-SCTP), is able to aggregate the... more
This paper introduces a transport layer solution for bandwidth aggregation, based on extending Stream Control Transmission Protocol (SCTP). The extended SCTP, which we refer to as Load-Sharing SCTP (LS-SCTP), is able to aggregate the bandwidth of the transmission ...
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Wireless Communications, Computer Networks, Pervasive Computing, Resource Allocation, Packet Switching, and 10 moreMobile Computing, Mobile Application, Bandwidth Allocation, Communication Channels, Transport Layer, Communications Technology, Bandwidth, Transport Protocols, Load sharing, and Stream Control Transmission Protocol
du Abstract- The increase in the bandwidth of wireless channels and the computing power of mobile devices increase the interest in video communications over wireless netw orks. However, the high error rate and the rapidly changing quality... more
du Abstract- The increase in the bandwidth of wireless channels and the computing power of mobile devices increase the interest in video communications over wireless netw orks. However, the high error rate and the rapidly changing quality of the radio channels can be devastating for the transport of compressed video. In motion compensated coding, errors due packet losses are propagated
Page 1. Bandwidth Aggregation in Stream Control Transmission Protocol Ahmed Abd El Al, Tarek Saadawi, Myung Lee Dept. ... CSCTP -CLS.SCTP 1 5 4 g 3.5 + 2.5 CO .I 1.5 4 0.5 SE. 2 P I 0 ' I " 9 Z 8 4 8 4 3 3 8 Z 8 Difference in... more
Page 1. Bandwidth Aggregation in Stream Control Transmission Protocol Ahmed Abd El Al, Tarek Saadawi, Myung Lee Dept. ... CSCTP -CLS.SCTP 1 5 4 g 3.5 + 2.5 CO .I 1.5 4 0.5 SE. 2 P I 0 ' I " 9 Z 8 4 8 4 3 3 8 Z 8 Difference in Paths Delay (mSec.) ...
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As recommended, broadband ISDN is expected to carry all the telecommunications services provided in the future, including real time services such as telephony, videoconferencing, and videotelephony. An ATM based network will introduce... more
As recommended, broadband ISDN is expected to carry all the telecommunications services provided in the future, including real time services such as telephony, videoconferencing, and videotelephony. An ATM based network will introduce some impairments not experienced in synchronous networks, such as cell delay variation (jitter) and cell loss. For these real-time services, if a cell is corrupted or lost, retransmission is not possible and so degradation of the signal may occur. In this paper, we study the impact of cell loss on speech quality over ATM networks. Moreover, we compare the results between two different cell loss's replacement techniques: stuffing silent samples and inserting the previous information in the lost cell. Study shows that the second replacement techniques produces better result when compared with the first one. The study also shows that up to 10% of speech cells can be lost over ATM networks while keeping the speech quality over MOS (Mean Opinion Score) of 3.2 for some speech coders. Understanding of the impact of cell loss on speech quality over ATM networks is important for the proper design of network algorithms such as routing, flow control, and management techniques.
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... Performance Evaluation of TCP Algorithms in Multi-hop Wireless Packet Networks. ... Revealing and Solving the TCP Instability Problem in 802.11 based Multi-hop Wireless Networks. ... In fact, by using DA, the reduction for the number... more
... Performance Evaluation of TCP Algorithms in Multi-hop Wireless Packet Networks. ... Revealing and Solving the TCP Instability Problem in 802.11 based Multi-hop Wireless Networks. ... In fact, by using DA, the reduction for the number of ACK packets traveling in the network, many ...
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In this paper, we report and reveal an unfairness problem among TCP connections in an IEEE 802.11-based wireless multi-hop network. This problem is not the same as those unfairness problems reported before. In each of the cases we... more
In this paper, we report and reveal an unfairness problem among TCP connections in an IEEE 802.11-based wireless multi-hop network. This problem is not the same as those unfairness problems reported before. In each of the cases we identified, the one TCP connection is completely shut down, even if it starts much earlier than the competing TCP traffic. By illustrating the TCP layer and MAC layer traces, we show that this kind of unfairness problem is rooted in the IEEE 802.11 MAC layer. The hidden node problem and the exposed node problem along with the exponential back-off scheme in the MAC layer are the major causes for that problem
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... network. In fact, no existing work, including the latest papers on 802.11 unfairness [12-14], ever talks about these problems. ... Prakash. A Feedback Based Scheme ForImproving TCP Performance in Ad-Hoc Wireless Networks. Proceedings... more
... network. In fact, no existing work, including the latest papers on 802.11 unfairness [12-14], ever talks about these problems. ... Prakash. A Feedback Based Scheme ForImproving TCP Performance in Ad-Hoc Wireless Networks. Proceedings ...
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Generally speaking, the parameter-based call admission control (CAC) approaches are conservative and lead to low network utilization since they use a worst-case model to ensure complete commitment conformance. Even if additional... more
Generally speaking, the parameter-based call admission control (CAC) approaches are conservative and lead to low network utilization since they use a worst-case model to ensure complete commitment conformance. Even if additional information of the new connection is available, they cannot take advantage of it. In this paper, we introduce some enhancements to the existing parameter based CAC algorithms for those applications in which one or two simple additional traffic characteristics are available, i.e. mean rate of the new connection and its rate variance. As well as showing how to do this, we give the reasons why we do this. We show that with these simple additional parameters, a much higher network utilization can be achieved. The numerical results demonstrate that the number of calls admitted to the network with our schemes is very close to (even equals) the best value
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The admission control and bandwidth allocation for ATM (asynchronous transfer mode) networks are studied. A dynamic bandwidth allocation algorithm is proposed and shown to improve the bandwidth equitable accessibility and the overall... more
The admission control and bandwidth allocation for ATM (asynchronous transfer mode) networks are studied. A dynamic bandwidth allocation algorithm is proposed and shown to improve the bandwidth equitable accessibility and the overall throughput. The algorithm is evaluated and compared with other allocation algorithms using blocking rate and cell throughput as evaluation criteria. An on-going study of the user-controlled bandwidth variation
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The asynchronous transfer mode (ATM) is considered a viable transport multiplexing technique for broadband integrated services digital networks (B-ISDNs). The impact on ATM network performance due to the varying bandwidth of services used... more
The asynchronous transfer mode (ATM) is considered a viable transport multiplexing technique for broadband integrated services digital networks (B-ISDNs). The impact on ATM network performance due to the varying bandwidth of services used is analyzed. A means of controlling the bandwidth crossover is presented. It is shown that, as more calls cross over from a lower to higher bandwidth, the network suffers from higher connection blocking. The crossover availability declines as more calls cross over and increase the bandwidth used. A slight increase in overall throughput is observed, since the network carries more crossover calls with the increased bandwidth. It is also shown that limitations can be placed on the amount of bandwidth that the crossover calls can occupy to protect the constant-bandwidth calls and keep and network connection blocking below a certain level. A dynamic bandwidth allocation algorithm is presented and evaluated as advantageous in terms of equitable bandwidth accessibility and overall cell throughput improvement
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... The other TCP variants suffer from this problem, including TCP New Reno (corresponding results not shown here). ... Those TCP variants suffering from this problem show worse throughput performance than Vegas. We suggest that use Vegas... more
... The other TCP variants suffer from this problem, including TCP New Reno (corresponding results not shown here). ... Those TCP variants suffering from this problem show worse throughput performance than Vegas. We suggest that use Vegas if possible. ...
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IEEE 802.11 MAC protocol is the standard for wireless LANs, it is widely used in testbeds and simulations in the research for wireless multi-hop ad hoc networks. However, this protocol was not designed for multi-hop networks. Although it... more
IEEE 802.11 MAC protocol is the standard for wireless LANs, it is widely used in testbeds and simulations in the research for wireless multi-hop ad hoc networks. However, this protocol was not designed for multi-hop networks. Although it can support some ad hoc network architecture, it is not intended to support the wireless mobile ad hoc network, in which multi-hop
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... 3. Sayantan Choudhury and Jerry D. Gibson "Joint PHY/MAC Based Link Adaptation for Wireless LANs with multipath fading", IEEE Wireless ... 11. David B. Johnson , David A. Maltz , Josh Broch, DSR: the dynamic source routing... more
... 3. Sayantan Choudhury and Jerry D. Gibson "Joint PHY/MAC Based Link Adaptation for Wireless LANs with multipath fading", IEEE Wireless ... 11. David B. Johnson , David A. Maltz , Josh Broch, DSR: the dynamic source routing protocol for multihop wireless ad hoc networks, Ad ...
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A mobile ad-hoc wireless network is a dynamically changing network of mobile devices that communicate without the support of a fixed infrastructure. There is a direct communications among the neighboring devices, but non-neighboring... more
A mobile ad-hoc wireless network is a dynamically changing network of mobile devices that communicate without the support of a fixed infrastructure. There is a direct communications among the neighboring devices, but non-neighboring devices require a robust and intelligent routing strategy to ensure reliable and efficient communications. However, in such networks there is no guaranteed end-to-end quality of service (QoS) and packets may be discarded due to bit errors. On the other hand there has been an increased demand to maintain the video quality over mobile ad-hoc networks. In this talk we will address some of the techniques to enhance quality of services for video delivery over mobile ad-hoc wireless networks. These techniques are implemented either in the MAC layer, in unicast/multicast routing, or in the applications layers. In the first part of the talk, we will present a multipath error recovery technique for video transmission using multipath retransmission scheme. A video...