GARP : A Highly Reliable Grid Based Adaptive Routing Protocol for Underwater Wireless Sensor Networks

Khaled Day, Abderezak Touzene, Bassel Arafeh, and Nasser Alzeidi 

Department of Computer Science, Sultan Qaboos University, Muscat, Oman 

ABSTRACT 

We make use of the existence of cell-disjoint paths in the 3D grid topology to design a new highly reliable adaptive geographic routing protocol called Grid-based Adaptive Routing Protocol (GARP) for Underwater Wireless Sensor Networks. In GARP, the underwater environment is viewed as a virtual 3D grid of cells. A packet is forwarded following a pre-constructed routing path from a node in a grid cell to a node in a neighbouring grid cell repeatedly until the destination sink node is reached. When a selected routing path becomes unavailable, GARP adapts to the condition by switching to an alternative path making use of the existing cell-disjoint paths. Since the protocol uses pre-constructed routing paths, it avoids path establishment and path maintenance overheads. Analytical performance evaluation results for GARP are obtained showing its high reliability. In tested cases, the delivery ratio has approached 100% when the network density has reached a minimum number of sensor nodes per grid cell. 

KEYWORDS 

Underwater Wireless Sensor Networks, Routing Protocol, Adaptive Routing, Disjoint Paths, 3D Grid

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Performance Analysis of Channel Capacity and Throughput of LTE Downlink System

P.Poornima1 , G. Laxminarayana2 and D. Srinivas Rao3

 1Associate Professor, Dept. of ECE, Sphoorthy Engineering College, Hyderabad, India 

2 Professor, Dept. of ECE, Anurag College of Engineering, Hyderabad, India 

3 Professor, Dept. of ECE, JNTUH CEH, Kukatpally, Hyderabad, India 

ABSTRACT 

In this paper, we analyzed a numerical evaluation of the performance of MIMO radio systems in the LTE network environment. Downlink physical layer of the OFDM-MIMO based radio interface is considered for system model and a theoretical analysis of the bit error rate of the two space-time codes (SFBC 2×1 and FSTD 4×2 codes are adopted by the LTE norm as a function of the signal to noise ratio. Analytical expressions are given for transmission over a Rayleigh channel without spatial correlation which is then compared with Monte-Carlo simulations. Further evaluated channel capacity and simulation results show throughput almost reaches to the capacity limit. 

KEYWORDS 

Channel Capacity, MIMO, OFDM, LTE Downlink, Spate time Block Coding and Throughput. 

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Performance Analysis of R/KADEMLIA, Pastry and Bamboo Using Recursive Routing in Mobile Networks

Farida Chowdhury1 and Md. Sadek Ferdous2 1

Department of Computer Science and Engineering, Shahjalal University of Science and Technology, Sylhet, Bangladesh 2

Electronics and Computer Science, University of Southampton, Southampton, UK 

ABSTRACT 

We are experiencing a revolution in the wireless technology and mobile phone networks as they are becoming increasingly ubiquitous. On the other hand, there is another trend, gaining extreme popularity over the traditional wired Internet: Peer-to-Peer (P2P) networking. Specifically, Distributed Hash Table (DHT) based Structured P2P overlay networks are capable to facilitate information storage and retrieval among a potentially very large number of users without the use of central server components. Providing such P2P services in mobile networks will allow a user to harness the potential of P2P services while on the move. However, due to technical issues in mobile phone networks and limited resources available on the handsets, designing such a system is a challenging issue. While the research of P2P overlays in wired networks is plenty, there is a limited study on the suitability of different existing P2P overlays for mobile networks. This article investigates the performance and efficiency of a number of structured P2P overlays that use recursive approach for routing strategy: R/Kademlia, Pastry and Bamboo and finds their suitability for use on mobile networks. The simulation result shows that among the three overlays, Bamboo exhibits a marginally better performance in comparison to the others with a 98% to 99% routing efficiency and a lower bandwidth consumption in high churn environment. Hence, Bamboo protocol is a good choice to be used over Kademlia and Pastry in mobile networks.

KEYWORDS 

Peer-to-Peer, Distributed Hash Table, Churn, Mobile Networks

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A Low Complexity User Grouping Strategy for Downlink Multi-User MIMO Scheduling

Nguyen Ngoc Van 

School of Electronics and Telecommunications, Hanoi University of Science and 

Technology, No 1 , Dai Co Viet Street, Hai Ba Trung, HaNoi, Vietnam 

ABSTRACT 

In this paperwe present a low complexity user grouping algorithm for multi-user MIMO system employing opportunistic fair scheduling (OFS) and zero forcing beamforming (ZFB), and develop a framework for cross-layer resource scheduling. Given a particular subset of users and their channel conditions, the optimal beamforming scheme can be calculated. The multi-user esource scheduling problem then refers to the selection of the optimal subset of users for transmission at each time instant to maximize the total throughput of the system. The simulation result shows that the performance of resource scheduling algorithm based on user grouping method proposed in this paper is close to the optimal performance which used exhaustion method. In addition, user grouping does not affect the fairness among all users.

KEYWORDS : 

Opportunistic fair scheduling (OFS); zero-forcing beamforming (ZFB); 

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A Novel Approach for Optimizing Energy and Bandwidth Issues in MANET Using DSR Protocol

Ajay Lala, Anand Bhaskar, Prasun Chakrabarti and JitendraKaushal Srivastava 

Department of Computer Science & Engineering, Sir PadampatSinghania University, Udaipur, Rajasthan, India  

ABSTRACT

An ad-hoc network is a cluster of wireless mobiles nodes which are self-making, self-arranging and selfregulating. Numerous energy conserving routing conventions have been proposed for Mobile Ad Hoc Network (MANET). Those conventions demonstrate that energy utilization in MANET can be reduced by modifying the transmit energy to a base level. To decide the base transmit power is a testing issue. This paper proposes a novel approach for optimizing Energy Issues in MANET using DSR Protocol convention which guarantees high reliability of the system. The Dynamic Source Routing (DSR) convention has been adjusted with a specific end goal to execute IE-DSR convention. Existing control messages of DSR convention have been adjusted and utilized as a part of IE-DSR convention. The proposed method introduces a systematic model to demonstrate that an impressive part of energy can be spared by utilizing IE-DSR convention. This calculation lessens the flooding of RREQ (route request) packets in the network which brings about the reduced energy utilization. The proposed calculation precludes the superfluous flooding of RREQ packets.

Based on the experimental work, the proposed method outperforms in reducing energy consumption by a rationale factor. Further, the simulation results depict that if the initial energy of node is kept relatively small then our proposed approach consumes approx. 70 % less energy than DSR, which is quite significant while comparing with the existing energy optimizing methods and it has been analyzed that an 15.36% of more data packet has been delivered to the appropriate destination. The application of the proposed method ensures larger network life, high reliability and lower cost estimation.

KEYWORDS

Ad-hoc Networks, IE-DSR, Flooding, RREQ, Routing Protocols;

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AN ANALYSIS OF THE FAT-TAILEDNESS OF THE CENTRALITY DISTRIBUTIONS OF REAL-WORLD NETWORKS

Natarajan Meghanathan Jackson State University, MS, USA 

ABSTRACT 

"Kurtosis" has long been considered an appropriate measure to quantify the extent of fat-tailedness of the degree distribution of a complex real-world network. However, the Kurtosis values for more than one realworld network have not been studied in conjunction with other statistical measures that also capture the extent of variation in node degree. Also, the Kurtosis values of the distributions of other commonly centrality metrics for real-world networks have not been analyzed. In this paper, we determine the Kurtosis values for a suite of 48 real-world networks along with measures such as SPR(K), Max(K)-Min(K), Max(K)-Avg(K), SD(K)/Avg(K), wherein SPR(K), Max(K), Min(K), Avg(K) and SD(K) represent the spectral radius ratio for node degree, maximum node degree, minimum node degree, average and standard deviation of node degree respectively. Contrary to the conceived notion in the literature, we observe that real-world networks whose degree distribution is Poisson in nature (characterized by lower values of SPR(K), Max(K)-Min(K), Max(K)-Avg(K), SD(K)/Avg(K)) could have Kurtosis values that are larger than that of real-world networks whose degree distribution is scale-free in nature (characterized by larger values of SPR(K), Max(K)-Min(K), Max(K)-Avg(K), SD(K)/Avg(K)). We also observe the Kurtosis values of the betweenness centrality distributions of the real-world networks to be more likely the largest among the Kurtosis values with respect to the commonly studied centrality metrics. 

KEYWORDS

 Fat-tailedness, Degree Distribution, Kurtosis, Real-World Networks, Centrality Metrics, Concordance  

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TOP 10 Computer Networks & Communications Research Articles- 2017 Fall (September)

TOP 10 Computer Networks & Communications Research Articles- 2017 Fall (September)

TOP 1  

DELAY-POWER PERFORMANCE COMPARISON OF MULTIPLIERS IN VLSI CIRCUIT DESIGN 

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