Abstract
Wireless sensor networks are often utilized in different kinds of applications like healthcare, military operations, border security, road and pipeline monitoring etc. The majority of these applications use fixed network topology and place sensors in a linear form defined as a linear sensor network (LSN). The Linear sensor networks have gained much attraction of the researchers due to their several positive aspects including easy deployment for linear structures and robustness in different environments. The details about the LSN models and routing techniques are mostly overlooked in the previous studies. This study, therefore, explores the concept of LSNs models and routing techniques in various types of applications. Besides, it highlights the LSN design, classification, challenges and issues as well. The core motivation for this study is to summarize the types of LSNs and analyze their routing parameters i.e. energy efficiency, reliability, route discovery, route maintenance, coverage, delay, heterogeneity and mobility of sensors. Moreover, recent LSN techniques are classified according to the similarities of routing procedures. Further, this study has investigated and discussed various proposed solutions, future directions and opportunities that would serve as a milestone for other researchers so that they could explore further the LSN routing techniques more deeply.