Papers by Somprakash Bandyopadhyay
Globecom '00 - IEEE. Global Telecommunications Conference. Conference Record (Cat. No.00CH37137)
The objective of this paper is to propose a mechanism for adaptive computation of multiple paths ... more The objective of this paper is to propose a mechanism for adaptive computation of multiple paths to transmit a large volume of data packets from a source s to a destination d in ad hoc wireless networks. We consider two aspects in this framework. The first aspect is to perform preemptive route rediscoveries before the occurrence of route errors while transmitting a large volume of data from s to d. Consequently, this helps find out dynamically a series of multiple paths in temporal domain to complete the data transfer. The second aspect is to select multiple paths in spatial domain for data transfer at any instant of time and to distribute the data packets in sequential blocks over those paths in order to reduce congestion and end-to-end delay. The performance of this approach has been evaluated to show the improvement in the quality of service. It has been observed that the mechanism allows any source to transmit a large volume of data to a destination without degradation of performance due to routeerrors. Additionally, it would help reduce significantly the endto-end delay and the number of route-rediscoveries needed in this process.
2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514)
Inter-vehicular communication (IVC) on highways is one of the major application areas of ad hoc n... more Inter-vehicular communication (IVC) on highways is one of the major application areas of ad hoc networks that enable multi-hop data exchange and forwarding between cars and between car and stationary gateways. In an IVC scenario, some emergency situations on highways may require an immediate communication with police, hospitals, highway assistance booth or with other cars. These messages should be forwarded on a top priority basis to the destination for immediate attention. So it is evident that, in an IVC scenario, some message flows are to be treated as high priority messages in order to ensure a timely and reliable delivery. In this paper, we have proposed a prioritybased communication scheme, which essentially selects shortest path for a high priority flow and reserves a zone known as high priority zone, along this path. Other low priority flows are forced to avoid this zone and take a longer diverse route to forward their messages to allow a contention-free communication to high priority flows. In this context, the use of directional antenna, having smaller transmission beam-width and larger transmission range compared to omni-directinal antenna, helps to easily decouple interfering routes, and improves the overall utilization of the wireless medium through Space Division Multiple Access (SDMA).
A distributed mechanism for topology discovery in ad hoc wireless networks using mobile agents
2000 First Annual Workshop on Mobile and Ad Hoc Networking and Computing. MobiHOC (Cat. No.00EX444)
... http://www.media.mit.edu/-nelson/research/routes-bookchapterl [5] Steve Appeleby and S.Stewar... more ... http://www.media.mit.edu/-nelson/research/routes-bookchapterl [5] Steve Appeleby and S.Steward.Mobile software agents for control in Telecommunications networks. ... ____ Fig. 1 Variation of Average Link-Affinity Convergence with time using Predictive Mechanism ...
IEEE Global Telecommunications Conference Workshops, 2004. GlobeCom Workshops 2004.
Existing priority-based QoS routing protocols in ad hoc wireless networks did not consider the ef... more Existing priority-based QoS routing protocols in ad hoc wireless networks did not consider the effect of mutual interference between routes in wireless medium during routing. We have investigated the effect of mutual interference on the routing performance in wireless environment and explored the advantage of using zone-disjoint routes to avoid mutual interference and to improve the network performance. In this paper, a priority based QoS routing scheme is proposed that uses the notion of zone-disjoint routes. Our protocol avoids the contention between high and low priority routes by reserving high priority zone of communication. Low priority flows will try to avoid this zone by selecting routes that is maximally zonedisjoint with respect to the high priority reserved zone and will consequently allow a contention-free transmission of high priority traffic in that reserved zone. If, under some unavoidable situations, a low priority flow has to go through high priority reserved zone causing interference then it will block itself temporarily to allow contention-free transmission of high priority flows and later may resume the blocked communication if possible. We have evaluated the effectiveness of our proposed protocol on QualNet network simulator.
1999 IEEE International Conference on Personal Wireless Communications (Cat. No.99TH8366)
A mobile, multi-hop wireless computer network, also termed as ad-hoc network, can be envisioned a... more A mobile, multi-hop wireless computer network, also termed as ad-hoc network, can be envisioned as a collection of routers, equipped with wireless transmitter / receiver, which are free to move about arbitrarily. The basic assumption in an ad-hoc network is that some node willing to communicate may be outside the wireless transmission range of each other but may be able to communicate if other nodes in the network are willing to forward packets from them. However, the successful operation of an ad-hoc network will be hampered, if an intermediate node, participating in a communication between two nodes, moves out of range suddenly or switches itself off in between message transfer. The objective of this paper is to introduce a parameter, affinity, that characterizes the strength of relationship between two nodes and to propose a distributed routing scheme between two nodes in order to find a set of paths between them which are more stable and less congested in a specific context. Thus, the communication in an ad-hoc wireless network can be effective by making the nodes in the system communication-aware in the sense that each node should know its affinity with its neighbors and should be aware of the impact of its movement on the communication structure of the underlying network.
A Fair Medium Access Protocol Using Adaptive Flow-Rate Control Through Cooperative Negotiation Among Contending Flows in Ad Hoc Wireless Network with Directional Antenna
Lecture Notes in Computer Science, 2004
Lecture Notes in Computer Science, 2003
Multipath routing protocols are distinguished from single-path protocol by the fact that they use... more Multipath routing protocols are distinguished from single-path protocol by the fact that they use several paths to distribute traffic from a source to a destination instead of a single path. Multipath routing may improve system performance through load balancing and reduced end-to-end delay. However, two major issues that dictate the performance of multipath routinghow many paths are needed and how to select these paths. In this paper, we have addressed these two issues in the context of ad hoc wireless networks and shown that the success of multipath routing depends on the effects of route coupling during path selection. Route coupling, in wireless medium, occurs when two routes are located physically close enough to interfere with each other during data communication. Here, we have used a notion of zone-disjoint routes to minimize the effect of interference among routes in wireless medium. Moreover, the use of directional antenna in this context helps to decouple interfering routes easily compared to omni-directional antenna.
Lecture Notes in Computer Science, 2003
The use of directional antenna in wireless ad hoc networks largely reduces radio interference, th... more The use of directional antenna in wireless ad hoc networks largely reduces radio interference, thereby improving the utilization of wireless medium and consequently the network throughput, as compared to omnidirectional antenna, where nodes in the vicinity of communication are kept silent. In this context, researchers usually assume that the gain of directional antennas is equal to the gain of corresponding omni-directional antenna. However, for a given amount of input power, the range R with directional antenna will be much larger than that using omni-directional antenna. In this paper, we propose a two-level transmit power control mechanism in order to approximately equalize the transmission range R of an antenna operating at omnidirectional and directional mode. This will not only improve medium utilization but also help to conserve the power of the transmitting node during directional transmission. The performance evaluation on QualNet network simulator clearly indicates the efficiency of our protocol.
International Parallel and Distributed Processing Symposium/International Parallel Processing Symposium, 2001
Realizing high volume real time communication in a highly dynamic architecture like Mobile Ad hoc... more Realizing high volume real time communication in a highly dynamic architecture like Mobile Ad hoc Networks (MANET) still remains a major point of research. In this paper, we have attempted to address the issue of maintaining an uninterrupted session between a source and a destination through multiple paths in a temporal domain. We have tried to develop an agent-centric protocol
Mobile and Wireless Communications, 2003
Multipath routing protocols are distinguished from single-path routing by the fact that they look... more Multipath routing protocols are distinguished from single-path routing by the fact that they look for and use several routes from a source to destination. Several routing schemes have been proposed in the context of mobile ad hoc networks that uses multiple paths simultaneously by splitting the information among the multitude of paths. However. the effect of route coupling in this environment can severely limit the gain offered by multipath routing strategies. Route coupling is a phenomenon of wireless medium and occurs when multiple routes are located physically close enough to interfere with each other during data communication. In this paper, we investigate the effect of directional antenna on multipath routing. We have shown that the effect of route coupling across multiple paths with directional antenna is much less compared to that with omni-directional antenna. As a result, the routing performance using multiple paths improves substantially with directional antenna compared to that with omni-directional antenna.
2008 First ITU-T Kaleidoscope Academic Conference - Innovations in NGN: Future Network and Services, 2008
Advances in wireless personal area networks have made the practical deployment of various service... more Advances in wireless personal area networks have made the practical deployment of various services possible, which until a few years ago was considered extremely costly or labor intensive. We build such a wireless sensor network for precision agriculture where real time data of the climatological and other environmental properties are sensed and relayed to a central repository. The architecture comprises of three distinct sections -(a) the sensor-nodes (b) the wireless mesh network and (c) the actuation components. The sensors are selected based on the properties suited for the most common crops and we identify four such attributes. The sensor network is based on the IEEE-802.15.4 standard and we develop a new static routing algorithm suited for the sensing application. The algorithm overrides the deficiency of the Hierarchical Routing scheme inherent in the ZigBee specification where the C skip addressing algorithm limits the possible depth of the network topology due to address wastage. The new algorithm maintains the hierarchical network topology and thus ensures routing at its optimal best. The algorithms for both addressing and routing are provided. The actuation components are also a part of mesh network and are activated wirelessly for controlling irrigation and fertigation.
There has been a growing interest in mobile, ad hoc wireless networks in recent years. In this en... more There has been a growing interest in mobile, ad hoc wireless networks in recent years. In this environment, all nodes are normally assumed to operate with a fixed transmission range. However, it has been observed that a low transmission range of mobile hosts will not guarantee proper connectivity among them to ensure effective communication. On the other hand, if the transmission range is high, it will ensure connectivity but will increase collision and congestion of control packets, which will increase the end-to-end delay significantly. Hence, a protocol based on variable transmission range for connectivity control would be highly effective in such a dynamic environment. Additionally, because of mobility, a node involved in a communication process may move out of the fixed transmission range of the sender, thus disturbing the communication process. Our transmission range control mechanism will try to protect connectivity between any two nodes involved in a communication process at that instant of time by adjusting their transmission ranges. Thus, the proposed scheme eliminates the need for route maintenance during data communication in ad hoc networks.
There has been a growing interest in mobile, multi-hop wireless networks in recent years. One of ... more There has been a growing interest in mobile, multi-hop wireless networks in recent years. One of the major concerns in this context is to design a communication protocol that provides QoS guarantee. Because of mobility, a node involved in the communication process may move out of the fixed transmission range of the sender, thus disturbing the communication process. In this paper, a mechanism is proposed based on self-adjusting variable transmission range of mobile hosts, which will not allow this to happen during a communication process. At the same time, variable transmission range of mobile hosts will allow us to control the congestion of control packets in a dynamic setting which would in turn reduce the end-to-end delay in data communication.
Multiaccess, Mobility and Teletraffic in Wireless Communications: Volume 5, 2000
Survivability analysis and drawing up a specification for a survivable ad hoc network is an impor... more Survivability analysis and drawing up a specification for a survivable ad hoc network is an important issue that we want to address in this paper. In this paper, we have concentrated on general class of ad hoc networks as well as a special class of ad hoc networks that relies on evaluating link stability and path stability to ascertain the life-span of a path before routing data packets. We have assayed the behavior of the ad hoc network as a whole and analyzed trends in the inter-parameter dependencies, with the objective of addressing to the survivability issues. We have finally drawn out an operating region of survivability for mobile ad hoc wireless networks in terms of user declared specifications.
Global Telecommunications Conference, . GLOBECOM . IEEE, 2003
Application of multipath routing techniques in mobile ad hoc networks has been explored earlier, ... more Application of multipath routing techniques in mobile ad hoc networks has been explored earlier, as multipath routing may help to reduce end-to-end delay, perform load balancing and consequently improve throughput. However, it has also been shown that the success of multipath routing in ad hoc wireless network depends on network topology and channel characteristics can severely limit the gain offered
A mechanism to discover the geographical positions of mobile nodes in ad hoc wireless networks th... more A mechanism to discover the geographical positions of mobile nodes in ad hoc wireless networks through the implementation of a mobile-multi-agent based framework is investigated in this work. In other words, we have developed an agent based information exchange and navigation protocol in order to make each node in the network aware of the positions of other nodes. Our primary aim is to collect position-related information from each node in the network and distribute them periodically (as updates) to other nodes through mobile agents. The notion of stigmergic communication has been used through the implementation of a shared information cache in each node. We have used the GPS (Global Positioning System) support at each node for the extraction of geographical co-ordinates, velocity and direction of movement of each node. We have also incorporated a predictive mechanism which helps each node to predict the instantaneous positions of other nodes, based on the information that agents ha...
Journal of Network and Systems Management - JNSM, 2002
Supporting high volume of data transmission in a highly dynamic architecture like Mobile Ad hoc N... more Supporting high volume of data transmission in a highly dynamic architecture like Mobile Ad hoc Networks (MANET) still remains a major point of research. In this paper, we have attempted to address the issue of managing an uninterrupted connection between a source and a destination through multiple paths in a temporal domain. We have developed an agent-centric protocol that would accomplish uninterrupted communication over adaptively selected routes. The protocol ensures minimal consumption of network resources. We have organized this work in two logical steps. In the first part, we have described an agent-based framework with its associated protocols and mechanisms. The primary objective of this mobile multiagent framework is to make all nodes in the system topology-aware. We have used the GPS (Global Positioning System) support at each node for the extraction of geographical coordinates, velocity, and direction of movement of each node. The second part of the work attempts to make...
Mobile Ad Hoc Networks (MANET) have emerged as one of the most significant areas of research in t... more Mobile Ad Hoc Networks (MANET) have emerged as one of the most significant areas of research in the field of mobile computing. However, the dynamics of mobile, wireless ad hoc networks as a consequence of mobility and disconnection of mobile hosts pose a number of problems in designing proper routing schemes for effective communication between any source and destination. The protocols proposed so far in this context and mechanisms for data communication have failed to ensure a stable QoS in such an infrastructure primarily due to two main reasons. First, due to the dynamism of the ad hoc architecture, uninterrupted multimedia (or any other data) communication has to rely heavily on the changing link stability. And, second, on link failures, resuming communication requires the entire route-establishment process to be redone. This generates intolerable overhead and delay. In this paper, we address the problem of maintaining a stable route in a resource limited, dynamic architecture li...
International Conference on …, 2008
The rising popularity of multimedia applications and potential commercial usage of Mobile Ad hoc ... more The rising popularity of multimedia applications and potential commercial usage of Mobile Ad hoc network (MANET) clearly indicates that Quality of Service (QoS) support in MANETs is an unavoidable task. Essentially, Multimedia traffic should get preference over conventional data traffic during communication through some kind of priority-based mechanism to assure a timely and guaranteed delivery of multimedia data. In this paper, we have proposed a scheme for supporting QoS in MANET by classifying the traffic flows in the network into different priority classes, and giving different treatment to the packet injection rate of the flows belonging to different classes. In our suggested scheme, the MAC protocol of any intermediate node of a flow detects the presence of high priority traffic in its neighborhood (transmission/reception zone) and back-propagates this knowledge back to the source which then can adaptively control packet injection rate of the low priority flow. This will ensure the high priority flow to get desired access to the medium to maintain its flow-rate.
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Papers by Somprakash Bandyopadhyay