Analyzing the Performance of Multi-hop Underwater Acoustic Sensor Networks

Abstract

Abstract-Multi-hop underwater acoustic sensor networks constrain the performance of medium access control protocols. The efficiency of the well-known RTS-CTS scheme is degraded due to long propagation delays of such networks. Recently, interest in Aloha variants has surfaced; however, the performance of such protocols within the context of multi-hop networks is not well studied. In this paper, we identify the challenges of modeling contention-based medium access control protocols and present a model for analyzing Aloha variants for a simple string topology as a first step toward analyzing the performance of contention-based proposals in multi-hop underwater acoustic sensor networks.An application of the model suggests that Aloha variants are vary sensitive to traffic loads and network size.

Analyzing the performance of Aloha in string multi-hop underwater acoustic sensor networks

“…And the bandwidth of acoustic channels in water is onethousandth that of the radio channels. Thus, compared with wireless sensor networks (WSNs), the research on UASNs is featured by long propagation delay and limited bandwidth, which pose grand challenges to almost every layer of network protocol stack and applications [2][3][4][5][6][7][8].…”

“…In [7], the first analytical model is proposed for the contention-based protocols in string multi-hop networks, called string topology network model (STNM). The model provides a method for computing the expected network throughput and the probability of packets' delivery to the gateway from an arbitrary sensor.…”

“…In fact, the analytical model in [7] is questionable in three aspects. First, since the node cannot transmit two packets simultaneously, there is no collision among the packets sent by the same node.…”

An Improved Multi-Hop-Enabled Energy Efficient MAC Protocol for Underwater Acoustic Sensor Networks

“…ALOHA was used in multi-hop UASN for string topology in (Gibson et al, 2007). The slotted floor acquisition multiple access (S-FAMA) protocol for UWASN was introduced in (Molins and Stojanovic, 2007).…”

General optimization framework for surface gateway deployment problem in underwater sensor networks

“…Without knowing the specifics of the medium access protocols, we can assume a randomized protocol with either one of two medium access schemes, namely slotted vs. unslotted schemes. It has been shown in literature that due to the relatively high propagation delay of acoustic signals, slotted protocols behave as inefficiently as unslotted protocols do [19][20][21][22]. Therefore, we can assume that the channel utilization cannot exceed the theoretical maximum of approximately 0.18.…”