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State-of-the-art in protocol research for underwater acoustic sensor networks
- In Underwater Networks
, 2006
"... In this paper, architectures for two-dimensional and three-dimensional underwater sensor networks are discussed. A detailed overview on the current solutions for medium access control, network, and transport layer protocols are given and open research issues are discussed. Categories and Subject Des ..."
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Cited by 43 (0 self)
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In this paper, architectures for two-dimensional and three-dimensional underwater sensor networks are discussed. A detailed overview on the current solutions for medium access control, network, and transport layer protocols are given and open research issues are discussed. Categories and Subject Descriptors:
Prospects and Problems of Wireless Communication for Underwater Sensor Networks
"... This paper reviews the physical fundamentals and engineering implementations for efficient information exchange via wireless communication using physical waves as the carrier among nodes in an underwater sensor network. The physical waves under discussion include sound, radio, and light. We first pr ..."
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Cited by 24 (5 self)
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This paper reviews the physical fundamentals and engineering implementations for efficient information exchange via wireless communication using physical waves as the carrier among nodes in an underwater sensor network. The physical waves under discussion include sound, radio, and light. We first present the fundamental physics of different waves; then we discuss and compare the pros and cons for adopting different communication carriers (acoustic, radio, and optical) based on the fundamental first principles of physics and engineering practice. The discussions are mainly targeted at underwater sensor networks with densely deployed nodes. Based on the comparison study, we make recommendations for the selection of communication carriers for underwater sensor networks with engineering countermeasures that can possibly enhance the communication efficiency in specified underwater environments.
Mu-sync: a time synchronization protocol for underwater mobile networks
- in: WuWNeT ’08: Proceedings of the third ACM international workshop on Underwater Networks
, 2008
"... Although there are numerous time synchronization algo-rithms recently proposed for terrestrial wireless sensor net-works, none of these could be directly applied to underwater acoustic sensor networks. This is because they typically as-sume that the propagation delay is negligible, which is not the ..."
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Cited by 9 (0 self)
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Although there are numerous time synchronization algo-rithms recently proposed for terrestrial wireless sensor net-works, none of these could be directly applied to underwater acoustic sensor networks. This is because they typically as-sume that the propagation delay is negligible, which is not the case in underwater. Furthermore, the sensor nodes in underwater tend to have some degree of mobility due to wind or ocean current, which complicates the problem even more by introducing time-varying delay. In this paper, we propose a cluster-based synchronization algorithm for underwater acoustic mobile networks, called “MU-Sync”. Our design avoids frequent re-synchronization by estimating both the clock skew and offset. As underwa-ter mobile networks experience both time-varying and long propagation delay, previous works that estimate the clock skew using a single least square error linear regression tend to be inaccurate. In the MU-Sync, the clock skew is esti-mated by performing the linear regression twice over a set of local time information gathered through message exchanges. The first linear regression enables the cluster head to offset the effect of long and varying propagation delay; the second regression in turn obtains the estimated skew and offset. With the help of MAC-level time stamping, we can further reduce the nondeterministic errors that are commonly en-countered by those synchronization algorithms that rely on message exchanges.
Efficient error recovery using network coding in underwater sensor netowrks,” tech. rep.,
, 2006
"... Abstract. Before the wide deployment of underwater sensor networks becomes a reality, one of the challenges that needs to be resolved is efficient error recovery in the presence of high error rates, node mobility and long propagation delays. In this paper, we propose an efficient error-recovery sch ..."
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Cited by 8 (4 self)
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Abstract. Before the wide deployment of underwater sensor networks becomes a reality, one of the challenges that needs to be resolved is efficient error recovery in the presence of high error rates, node mobility and long propagation delays. In this paper, we propose an efficient error-recovery scheme that carefully couples network coding and multipath routing. Through an analytical study, we provide guidance on how to choose parameters in our scheme and demonstrate that our scheme is efficient in both error recovery and energy consumption. We evaluate the performance of our scheme using simulation and our simulation confirms the results from the analytical study.
Energy-Efficient Reliable Broadcast in Underwater Acoustic Network
- In Proc. of ACM International Workshop on Underwater Networks (WUWNet
, 2007
"... Underwater acoustic networks have the potential to support a large variety of applications, such as environmental and equipment monitoring. However, underwater protocol design is in its infancy. Although there has been some work in routing and MAC layer pro-tocols, they only address some of the chal ..."
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Cited by 5 (1 self)
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Underwater acoustic networks have the potential to support a large variety of applications, such as environmental and equipment monitoring. However, underwater protocol design is in its infancy. Although there has been some work in routing and MAC layer pro-tocols, they only address some of the challenges. A fundamental primitive that has not yet been researched for underwater networks is reliable broadcast. Reliable broadcast is required by many differ-ent applications, such as in-network node reprogramming. In this paper, we present three reliable broadcasting protocols (SBRB, FS-BRB, and DBRB) that address the specific challenges of the under-water channel. We also compare our approach to two standard re-liable broadcast protocols through extensive simulation, and show that our protocols provide significant gains in terms of both en-ergy consumption and time to complete the broadcast. Moreover, our results demonstrate the importance of addressing the peculiar relationship between bandwidth and distance exhibited by an un-derwater acoustic channel.
Fountain codes and their application to broadcasting in underwater networks: Performance modelling and relevant tradeoffs
- in Proc. 3rd ACM Int. WuWNeT
"... Our aim in this paper is to study the performance of broadcasting al-gorithms for underwater acoustic sensor networks (UWASNs). The targeted scenario is very simple; we consider a source (the initia-tor of the broadcast transmission) and a number of nodes randomly placed within a given geographical ..."
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Cited by 5 (1 self)
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Our aim in this paper is to study the performance of broadcasting al-gorithms for underwater acoustic sensor networks (UWASNs). The targeted scenario is very simple; we consider a source (the initia-tor of the broadcast transmission) and a number of nodes randomly placed within a given geographical area. For an efficient broad-cast transmission we advocate the use of a hybrid ARQ scheme, where Fountain Codes (FC) are exploited to enhance the efficiency of the data dissemination process in the face of poor and possi-bly unknown channel conditions. FC codes, being rateless, are in fact able to adapt to diverse error rates and correct packet losses on the fly through the transmission of additional redundancy pack-ets. The main contribution of this paper is a mathematical model to characterize the performance of fountain codes as applied to broad-casting in underwater networks. Our analysis allows us to find per-formance metrics such as transmission delay, reliability (e.g., per-centage of covered users) and power consumption. Relevant trade-offs are highlighted and quantified; in particular the implications of transmission power on covered distance, rate and delay are dis-cussed. Even though we do not propose a practical broadcasting protocol here, the results and tradeoffs we obtain are essential to a proper design of practical schemes.
Towards Optimal Broadcasting Policies for HARQ based on Fountain
- Codes in Underwater Networks,” in, Proc. of WONS 2008, Garmish-Partenkirken
"... Abstract—This paper explores hybrid ARQ policies based on Fountain Codes for the transmission of multicast messages in un-derwater channels. These rateless codes are considered because of two nice properties, namely, they are computationally lightweight and do not require to know the channel erasure ..."
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Cited by 4 (2 self)
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Abstract—This paper explores hybrid ARQ policies based on Fountain Codes for the transmission of multicast messages in un-derwater channels. These rateless codes are considered because of two nice properties, namely, they are computationally lightweight and do not require to know the channel erasure probabilities at the receivers prior to transmission. In this paper, these codes are used together with a Stop and Wait ARQ to enhance the performance of broadcast communications. First, we present a dynamic programming model for the characterization of optimal broadcasting policies. The derived broadcasting rules are then compared against plain ARQ schemes via Monte-Carlo simulation. Our results show that digital fountain codes are a promising technique for the transmission over underwater channels as their performance, in terms of delay, reliability and energy efficiency, clearly dominates that of plain ARQ solutions. This paper is a preliminary study on the topic and encourages us towards the design of practical HARQ protocols for the underwater medium. Index Terms—Underwater acoustic networks, broadcast, foun-tain codes, hybrid ARQ, optimal transmission policy. I.
Reliable event detection and congestion avoidance in wireless sensor networks,” Networking
, 2007
"... Abstract. Due to dense deployment and innumerable amount of traffic flow in wireless sensor networks (WSNs), congestion becomes more common phe-nomenon from simple periodic traffic to unpredictable bursts of messages trig-gered by external events. Even for simple network topology and periodic traffi ..."
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Cited by 3 (0 self)
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Abstract. Due to dense deployment and innumerable amount of traffic flow in wireless sensor networks (WSNs), congestion becomes more common phe-nomenon from simple periodic traffic to unpredictable bursts of messages trig-gered by external events. Even for simple network topology and periodic traffic, congestion is a likely event due to time varying wireless channel condition and contention caused due to interference by concurrent transmissions. Congestion causes huge packet loss and thus hinders reliable event perception. In this pa-per, we present a congestion avoidance protocol that includes source count based hierarchical medium access control (HMAC) and weighted round robin forwarding (WRRF). Simulation results show that our proposed schemes avoid packet drop due to buffer overflow and achieves more than 90 % delivery ratio even under bursty traffic condition, which is good enough for reliable event detection. 1
