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Tree-based Data Aggregation Algorithms in Wireless Sensor Networks: A Survey

Wireless sensor networks (WSN) are resource-constrained self-organizing networks that are often deployed in hostile and inaccessible environments in order to collect data. The reliability of WSN is affected by faults that may occur due to various reasons such as malfunctioning hardware, software glitches, dislocation, or environmental hazards. Appropriate fault tolerance mechanism will mitigate network failure and increase the entire network reliability. Moreover, WSN suffers from many constraints, including low computation capability, small memory, limited energy resources, and the use of insecure wireless communication channels. To overcome these limitations and achieve reliable data, many data aggregation algorithms have been proposed. The main goal of these data aggregation algorithms is to gather and aggregate data in an energy efficient manner so that the network lifetime can be increased. In this paper we present an elaborate survey on different data aggregation algorithms based on tree architecture and compare and contrast different algorithms on the basis of performance measures such as lifetime, energy consumption, synchrony, and robustness. We conclude with possible future research directions.