This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS... more
This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS HUB is implemented around a single PC with other subsystems making it very cost effective and unique of its kind. This realization will drastically reduce the total cost of Satellite based Education Networks as very low cost commercially available Satellite Interactive Terminals (SITs) complying to open standard could be used at remote locations. The system is successfully tested to work with a commercial SIT using a GEO satellite EDUSAT which is especially dedicated for satellite based e-Learning. The internal detail of the DVB-RCS Forward and Return Link Organization and how it manages the Satellite Interactive Terminals access to the satellite channel using MF-TDMA approach has been described.
A Body Area Network is a Wireless Network of wearable computing devices. With the advancement of microelectronics, communication and medical sciences, a Body Area Network, with the help of bio-signal sensors can collect relevant vital... more
A Body Area Network is a Wireless Network of wearable computing devices. With the advancement of microelectronics, communication and medical sciences, a Body Area Network, with the help of bio-signal sensors can collect relevant vital medical parameters in real-time and transfer it into a network for proactive healthcare and emergency mitigation services. In this paper, an attempt has been made to bring out the challenges for the development of a Satellite based Body Area Network. The paper discusses on the feasibility for the development of such a network, considering the available and future technologies. In this paper, the author addresses on the architecture, design, and development issues of such a novel network and come up with the applications and outcomes with possible services, which this type of network can offer both on a national and global scale. A Satellite based Body Area Network does not exists now, so the author also tries to bring out the necessary technological ch...
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In this paper, we will discuss the DVB-SH standard and address the need for mobile TV reception via satellite. The advantage of a satellite based mobile TV service compared to terrestrial based mobile TV service is emphasized in this... more
In this paper, we will discuss the DVB-SH standard and address the need for mobile TV reception via satellite. The advantage of a satellite based mobile TV service compared to terrestrial based mobile TV service is emphasized in this paper. The technical challenges of a satellite based mobile television reception technology are addressed. The salient features of the DVB-SH standard have been discussed and the features, which make the standard appropriate for mobile satellite networks, have been explained. Mobile Satellite Network requirements and how well DVB-SH handles those issues have been discussed. The paper also discusses the ongoing work in DVB-SH standard along with the inferences achieved from these experiments.
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This paper presents a sender side only TCP mechanism to prevent compromise for bandwidth uti-lization in IEEE 802.11 wireless networks. In absence of mechanism for accurate and immediate loss discrimination, the TCP sender unnecessarily... more
This paper presents a sender side only TCP mechanism to prevent compromise for bandwidth uti-lization in IEEE 802.11 wireless networks. In absence of mechanism for accurate and immediate loss discrimination, the TCP sender unnecessarily reduces its Loss Window in response to the packet losses due to transmission errors. At the same time, frequent transmission losses and as-sociated link retransmissions cause inaccuracy for available bandwidth estimate. The proposal, Adaptive TCP tackles the above issues using two refinements. First, sender estimates the degree of congestion by exploiting the statistics for estimated Round Trip Time (RTT). With this, it prevents unnecessary shrinkage of Loss Window and bandwidth estimate. Second, by concluding the unin-terrupted evolution of its sending rate in recent past, the Adaptive TCP advances bandwidth esti-mate under favorable network conditions. This in turn, facilitates for quick growth in TCP’s send-ing rate after loss recovery and consequ...
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Recent trends in field of wireless networks is setting up Wireless Sensor Networks that, senses specified parameter(s) related to environment; processes sensed data and wirelessly communicates it to a base station. Such networks open up a... more
Recent trends in field of wireless networks is setting up Wireless Sensor Networks that, senses specified parameter(s) related to environment; processes sensed data and wirelessly communicates it to a base station. Such networks open up a whole new range of applications, including precision agriculture, monitoring and tracking vehicles, animals and humans, battle-field surveillance, civil structural monitoring etc. All these applications require extended network lifetime, scalability, and traffic balancing among nodes in the network. Clustering is one of the effectual techniques for achieving these requirements. In clustering, geographically adjacent nodes are organized into virtual groups called clusters. One of the cluster node acts as a cluster head and rest as cluster members. This paper presents Cluster Head selection protocol using Fuzzy Logic (CHUFL). It uses node’s parameters like: residual energy, reachability from its neighborhood, quality of communication link with its ne...
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Round Trip Time values constitute one of the significant parameter available to a TCP sender for estimating the network conditions. The RTT has a significant effect on the throughput of a connection and creates the performance bottleneck... more
Round Trip Time values constitute one of the significant parameter available to a TCP sender for estimating the network conditions. The RTT has a significant effect on the throughput of a connection and creates the performance bottleneck for traditional AIMD TCP Protocol variants mainly when used for GEO satellite networks and other long fat networks. Many Transport Protocols like Vegas, Proactive TCP, and Westwood uses the RTT measurement for adjusting the congestion window and refining the Loss Detection Algorithms, which eventually determines the performance of the Protocol. RTT also appears in the empirical formulation of TCP throughput and protocols based on these empirical estimates. RTT is generally considered an independent parameter mainly dependent on the access delay, queuing delay, and the propagation delay of the concerned channel. In this paper, we have analyzed the dynamics of RTT behavior and shown how the congestion levels in the network, packet error rates and avai...
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This paper presents Fuzzy and Ant Colony Optimization (ACO) based MAC/Routing cross-layer protocol (FAMACRO) for W ireless Sensor Networks that encompases cluster head selection, clustering and inter-cluster routing protocols. FAMACRO us... more
This paper presents Fuzzy and Ant Colony Optimization (ACO) based MAC/Routing cross-layer protocol (FAMACRO) for W ireless Sensor Networks that encompases cluster head selection, clustering and inter-cluster routing protocols. FAMACRO us es fuzzy logic with residual energy, number of neighboring nodes and quality of communication link as input variables for cluster head selection. To avoid “hot spots”, FAMACRO uses an unequal clustering mechan ism with clusters closer to master station having smaller sizes than those far from it. Finally, ACO techinque is used for reliable and energy-efficient inter-cluster ro uting from cluster heads to master station. The inter-cluster routing protocol decides relay node considering its residual energy, d istance from current cluster head, distance from master station and packet reception rate. A comparative analysis of FAMACRO w ith Distributed Energy Efficient Hierarchical Clustering, Unequal Hybrid Energy Efficient Distributed Clustering, Energ...
TCP has become the de-facto protocol standard for congestion control in the existing terrestrial Internet. But it was designed keeping in mind low Round Trip Time and low channel error rates typically experienced in a wired network. In... more
TCP has become the de-facto protocol standard for congestion control in the existing terrestrial Internet. But it was designed keeping in mind low Round Trip Time and low channel error rates typically experienced in a wired network. In this paper we have considered TCP Protocol variants like Tahoe, Reno, New Reno, SACK, FACK, Vegas, Westwood and Peach. TCP Peach is found to be better than the other TCP Protocol variants in case of satellite based networks but its performance also degrades when the packet error probability is high and in cases where there are multiple packet losses in the same window. In this paper a modification has been suggested to the existing PEACH protocol and the modified PEACH Protocol is tested to provide performance improvement especially in the cases where the packet error rate is very high. The modified Peach Protocol has been implemented in the ns2 Simulator and evaluated considering a Geo Satellite Network with varying channel conditions with all other ...
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RTT is the only parameter available with TCP sender for estimating network capacity. Accordingly, legacy TCP revises its sending rate for utilizing maximum of the network capacity, without overloading. Since in wireless network, RTT is... more
RTT is the only parameter available with TCP sender for estimating network capacity. Accordingly, legacy TCP revises its sending rate for utilizing maximum of the network capacity, without overloading. Since in wireless network, RTT is weakly correlated to the congestion, any estimate using only the recent RTT sample may lead to performance penalty. This paper presents a simulation-based study of the two RTT-dependent mechanisms, targeting fair network state classification by taking RTT statistics into account. It is demonstrated that the performance of TCP scheme equipped with one technique can be improved further by tweaking using the other technique.
This paper presents a Low Energy Fuzzy based Unequal Clustering Multihop Architecture (LEFUCMA) for wireless sensor networks consisting of several nodes that send sensed data to a Master Station (MS). LEFUCMA encompasses neighbor finding,... more
This paper presents a Low Energy Fuzzy based Unequal Clustering Multihop Architecture (LEFUCMA) for wireless sensor networks consisting of several nodes that send sensed data to a Master Station (MS). LEFUCMA encompasses neighbor finding, cluster head selection, clustering and routing protocols. The neighbor finding protocol organizes the network into a sectored-layers structure. The cluster head selection uses fuzzy logic with residual energy, number of neighboring nodes, packet reception rate and distance of node from MS as fuzzy descriptors for cluster head selection. For even distribution of traffic, LEFUCMA uses fuzzy logic with node density and distance of area from MS as fuzzy descriptors to decide number of cluster heads in a given area. To avoid hot spots problem, LEFUCMA uses an unequal clustering mechanism with clusters closer to MS having smaller sizes than those farther from MS. Finally, inter-cluster routing protocol decides the next hop cluster head considering its residual energy, distance from MS and from current cluster head which represents energy required for communication, number of cluster members which represents intra-cluster traffic and number of descendant nodes which represents inter-cluster traffic. A comparative analysis of LEFUCMA; Unequal Hybrid, Energy Efficient and Distributed Clustering (Ever et al. in Proceedings of international conference on sensor networks, pp 185–193, 2012; Energy Aware Distributed Unequal Clustering (Yu et al. in Hindawi Int J Distrib Sens Netw, Article ID 202145:1–8, 2011); Constructing Optimal Clustering Architecture (Li et al. in J Comput Commun 36(3):256–268, 2013; and Energy Aware Unequal Clustering using Fuzzy logic (EAUCF) (Bagci and Yazici in J Appl Soft Comput 13(4):1741–1749, 2013) shows that LEFUCMA is 32–42% more energy efficient compared to EAUCF. Throughput of LEFUCMA is 46% more and network lifetime is 60–75% more compared to EAUCF.
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This paper introduces Fuzzy-Cross, a decision making and information-sharing architecture for wireless sensor networks (WSN)that enables the protocols to achieve energy efficiency, reliability,and low data latency. FUCRretains a layered... more
This paper introduces Fuzzy-Cross, a decision making and information-sharing architecture for wireless sensor networks (WSN)that enables the protocols to achieve energy efficiency, reliability,and low data latency. FUCRretains a layered structure with each layer matching to a communication function to provide a practical and simple design. The administrative plane provided by FUCR collects residual energy from physical layer, data delivery, and channel assessment records from data link layer, packet dispatch rate from network layer and sensitivity of sensing unit from application layer. The information collected is used as input descriptors for running fuzzy logic. Output of the fuzzy logic assists physical layer protocol to decide node's transmit power; data link layer protocol to decide retransmission time out, back off time and duty cycle; network layer to determine chance of the node to become a relay node and application layer to determine chance of node to become a reporting node. To investigate the extent to which Fuzzy-Cross meets its goals, it is implemented on top of ZigBee standard. Simulation results demonstrated that Fuzzy-Cross with ZigBee outperforms both (i) ADaptive Access Parameters Tuning (ADAPT) with Zigbee and (ii) standard ZigBee without any modifcations. For a single hop network Fuzzy-Cross is up to 12% more energy efficient compared to ADAPT. Delivery ratio of Fuzzy-Cross is up to 12% more and data latency is up to 19% less compared to ADAPT. Similar trend is seen for multi-hop network and for a wide range of operating conditions.
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This paper presents Fuzzy Based Unequal Clustering Protocol (FUCP) for wireless sensor networks. The cluster head selection mechanism uses fuzzy logic with three node descriptors namely, residual energy, centerness with respect to its... more
This paper presents Fuzzy Based Unequal Clustering Protocol (FUCP) for wireless sensor networks. The cluster head selection mechanism uses fuzzy logic with three node descriptors namely, residual energy, centerness with respect to its neighbor, and quality of communication link with its neighbors for cluster head selection. To avoid hot spots and for uniform network traffic distribution, FUCR uses unequal clustering. For this, fuzzy logic is used with node distribution and distance from master station to decide number of cluster heads and cluster head advertisement radius in a given area. A comparative analysis of FUCR, Low Energy Adaptive Clustering Hierarchy, Hybrid Energy Efficient Distributed Clustering, Cluster Head Election mechanism using Fuzzy logic, and Distributed Energy Efficient Hierarchical Clustering shows that FUCP is up to 40% more energy efficient, has 31% more network lifetime, and sends 57% more packets to master station compared to Distributed Energy Efficient Hierarchical Clustering.
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Summary Network utilization by legacy transmission control protocol (TCP) is determined by its round trip time (RTT) dependent mechanism for the growth of its sending rate. The RTT does not always reflect the actual network conditions,... more
Summary Network utilization by legacy transmission control protocol (TCP) is determined by its round trip time (RTT) dependent mechanism for the growth of its sending rate. The RTT does not always reflect the actual network conditions, especially in the case of wireless local area network (WLAN). Consequently, it influences the RTT-dependent mechanism falsely. This paper proposes a novel cross-layer scheme between TCP and the Institute of Electrical and Electronics Engineers (IEEE) 802.11 medium access control (MAC) that compensates for any diminished growth of TCP's sending rate because of the inclusion of non-congestion delay component in RTT, if any. The proposed scheme has two refinements. The first refinement is at the MAC layer that notifies the additional propagation delay on account of link retransmission of a TCP packet. The second refinement is at the TCP layer in which the sender adapts the sending rate by relating the aforementioned additional propagation delay to the RTT estimation. To examine the benefits, the proposed scheme is evaluated after implementing it on top of representative TCP variants; Newreno and Westwood+ (TCPW). Simulation results showed that with the proposed scheme, network utilization by native TCP is improved by more than 35% in a dedicated WLAN environment, while the performance remained protected in a shared WLAN environment. Copyright © 2015 John Wiley & Sons, Ltd.
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This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS... more
This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS HUB is implemented around a single PC with other subsystems making it very cost effective and unique of its kind. This realization will drastically reduce the total cost of Satellite based Education Networks as very low cost commercially available Satellite Interactive Terminals (SITs) complying to open standard could be used at remote locations. The system is successfully tested to work with a commercial SIT using a GEO satellite EDUSAT which is especially dedicated for satellite based e-Learning. The internal detail of the DVB-RCS Forward and Return Link Organization and how it manages the Satellite Interactive Terminals access to the satellite channel using MF-TDMA approach has been described. K EYWORDS
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This paper presents Self Organized, Flexible, Latency and Energy Efficient (SOFLEE) Protocol, a cross-layer protocol for Wireless Sensor Networks that uses TDMA based medium access scheme combined with multi-hop routing information during... more
This paper presents Self Organized, Flexible, Latency and Energy Efficient (SOFLEE) Protocol, a cross-layer protocol for Wireless Sensor Networks that uses TDMA based medium access scheme combined with multi-hop routing information during time slot allocation. Time slot allocation is done centrally by Master Station (MS) to provide a collision-free and fair media access. MS allocates same transmission slot to nodes that are two hops apart to increase channel spatial reuse and decrease data latency. For data gathering at MS, SOFLEE uses parenthood willingness to forward data to MS through unidirectional tree rooted at MS. Parenthood willingness of a node is decided using: (i) its location with respect to MS, to forward data in correct direction; (ii) its number of children, to prevent local congestion; (iii) its residual energy, to uniformly distribute energy load of being a parent node and (iv) its parent–child communication link reliability to guarantee consistent data delivery. The parenthood willingness requires simple comparisons against thresholds, and thus, is very simple to implement on memory and computationally constrained nodes. Unlike a conventional TDMA-based protocol, SOFLEE provides flexibility to transfer data slots among nodes and priority based slot scheduling to adapt to dynamic traffic patterns of various Wireless Sensor Network applications. Finally, simple, memory and energy efficient techniques for: (i) hop-by-hop congestion control; (ii) catering to orphan nodes, link breakdowns and node deaths are incorporated in SOFLEE. A comparative analysis of SOFLEE, FlexiTP, self organized TDMA protocol, energy efficient fast forwarding and D-MAC show that SOFLEE is 25 to 61 % more energy efficient compared to FlexiTP. Data latency of SOFLEE is 32 to 68 % less, delivery ratio is 7 to 19 %, goodput is 3 % and network lifetime is 253.784 s to 448.440 s more compared to FlexiTP.
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Research Interests: Computer Science, Design, Performance, Geo, Experimentation, and 5 moreComputer Applications, PER, RTT, Vegas, and Sack
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ISRO has established a facility known as Meteorological and Oceanographic Satellite Data Archival Center (MOSDAC) to facilitate and promote the exchange of satellite data (various products, metadata and other information) to the research... more
ISRO has established a facility known as Meteorological and Oceanographic Satellite Data Archival Center (MOSDAC) to facilitate and promote the exchange of satellite data (various products, metadata and other information) to the research and academic users. It also has ...
National Conference on Recent Developments in Computing and its Applications, NCRDCA'09 August 12-13, 2009 A Fusion of Non-Clustered with Clustered Network Topology for Performance Enhancement of Wireless Sensor Networks Aniruddha... more
National Conference on Recent Developments in Computing and its Applications, NCRDCA'09 August 12-13, 2009 A Fusion of Non-Clustered with Clustered Network Topology for Performance Enhancement of Wireless Sensor Networks Aniruddha Das1, M. Sarkar2 ...
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This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS... more
This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS HUB is implemented around a single PC with other subsystems making it very cost effective and unique of its kind. This realization will drastically reduce the total cost of Satellite based Education Networks as very low cost commercially available Satellite Interactive Terminals (SITs) complying to open standard could be used at remote locations. The system is successfully tested to work with a commercial SIT using a GEO satellite EDUSAT which is especially dedicated for satellite based e-Learning. The internal detail of the DVB-RCS Forward and Return Link Organization and how it manages the Satellite Interactive Terminals access to the satellite channel using MF-TDMA approach has been described.