Comparative study of wireless protocols : wi-fi, bluetooth, ZigBee, WirelessHART and ISA SP100, and their effectiveness in industrial automation
A decade ago, wireless technology was unimaginable in its application in industrial automation as wireless had poor reliability and security in the form of time delays and frame losses. Also, lack of interoperability and standards has been a barrier for wireless applications in control system. But with recent advancements in wireless technology, and with the underlying advantages of wireless like low infrastructural costs, scalability, mobility, and ability to operate in extreme and remote environments, many are seriously considering wireless for industrial automation solutions.
For wireless implementation in industries, it is important to understand its characteristics - security, update rates, data types, protocols, and latency time. Protocol being an important characteristic of any communication, is to be chosen intelligently for maximum efficiency. Because of the complexity of creating a communication protocol, existing information technology (IT) protocols such as Wi-Fi, Bluetooth, and ZigBee were used in industries. But as applications widened, and interoperability became an important factor to be considered, it was required to standardize the protocols used. ISA SP100 and WirelessHART are results of this standardizing process.
For the last few years, there has been a huge discussion on which of these protocols are robust and work better, and none has emerged as clear winners. The aim of this thesis is to explore the capabilities and limitations of each of these protocols for various industrial applications. This thesis considers all these protocols and helps choose the best fit for industrial applications and includes study of security, reliability, and efficiency of these protocols.