A Reliable Error Detection Mechanism in Underwater Acoustic Sensor Networks

Abstract

Underwater Acoustic Sensor Networks (UWASNs) are not secure due to various characteristics of underwater environments. The error rate is very high in underwater environment due to factors such as long propagation delay, fading, multi-path and noises. Moreover, malicious attacks to the network add one more threat to reliable data transport problems. With respect to terrestrial sensor network, UWASNs are very different in nature. Reliable and faster data communication is our main issue. As the signal has to travel inside a noisy wireless acoustic channel so the processing of the signal is also take to measure. Moreover, we know the error rate is always high in underwater, so detecting the error and correcting them is the main key to secure the communication among nodes. The energy efficiency as well as the performance of any mechanism depends on collusion free data transmission and reception among sensors. Data link layer plays a crucial part in the Media Access Control (MAC) operation by detecting errors. For secure communication it is necessary to detect the errors during the transmission and reception. Especially in data link layer, the error detection and correction used some techniques like Cyclic Redundancy Check (CRC), checksum, parity bit, Forward Error Correction (FEC) and different error-correcting codes like Humming code, Reed Solomon code, binary convolution code and others tailored made program. In UWASNs data throughput depends on the packet size and the MAC protocols, where different protocols perform differently. A valid packet size has a great effect on the network. The ideal packet sizes depend on the specific application and the pattern of message it generates. We have to use small size packets which do help faster communication and higher data throughput in UWASNs. In this paper, depends on our practical experience, instead of using any kind of FEC techniques, we used CRC-8 because the process of data transmission usually contains the risk of unwanted modification as the channel is open. Signals arrive to the physical layer at different power and delay due to acoustic effects. So packets need to re-check for reliable data communication in UWASNs.