Internet of Things Based Secured Data Transmission Protocol for Agriculture Application Pallavi Sunil Bangare * , Kishor P. Patil Department of E&TC, Sinhgad Academy of Engineering, Savitribai Phule Pune University, Pune 411048, India Corresponding Author Email: psbangare.sae@sinhgad.edu https://doi.org/10.18280/isi.280217 ABSTRACT Received: 27 September 2022 Accepted: 2 April 2023 In this research, we proposed a protocol for information transmission in a communication system. The protocol consists of three parts: Publisher, Broker, and Subscriber. The main problem in the transmission is the reliability of the broker. It is very difficult to get the status of the broker whether it is active or not. Secondly, we also worked on the part of security. Here by employing a Watchdog timer to determine whether the broker is active or not. To make the system more secure AES algorithm is incorporated into it. To validate the suggested protocol hardware setup is built and performance is tested in various conditions. Performance tests show that our proposed system outperforms the current system when compared to the existing system. The suggested system architecture's temporal and spatial complexity are also presented in this research. Keywords: communication system, IOT, security, MQTT, agriculture, SMO, AES 1. INTRODUCTION Multiple devices can communicate with one another using the lightweight messaging protocol MQTT. It utilizes the publish-subscribe method for communication and is a TCP- based protocol. Data communication between devices with limited resources and minimal power requirements is made possible by this protocol. As a result, the IoT Framework frequently uses this message protocol for communication. MQTT is a publish-and-subscribe protocol, so client devices and applications interact with topics managed by a broker rather than a server. MQTT uses several bi-directional transports in addition to IP (Internet Protocol) as its primary mode of transport. The MQTT broker is computer software that can be either self-created or a third-party host. There are both open source and proprietary options. Under this strategy, several clients interact with one another, but there is no established relationship between them. Every client communicates with every other client via a Broker, a third- party middleman. In a way, the broker functions like a post office. Instead of using the intended recipient's direct connection address, MQTT clients use the "Topic" topic line. A copy of every message associated with a topic will be sent to anyone who subscribes to it. While a single broker can subscribe many clients and a client can do the registration with multiple brokers. (One to many capabilities) (many to one). The TCP/IP layered protocol paradigm can be viewed of as an extension of the stack of IoT protocol, which comprises of the physical layer, network layer, link layer, transport layer, application services layer and application protocol layer. The idea behind the Internet of Things (IoT) is to link common household appliances to the web. Even though communication is crucial to the IoT, the variety of IoT use cases makes it one of the trickiest issues to solve. It might be challenging to identify the optimal protocol for a specific solution because there are so numerous network technologies available to suit communication needs. The data are analyzed using a Merkle Tree. An extension of the hash list, as a hash-based data structure, a Merkle tree. Non leaf node represents a hash of a node's children, and every leaf node represents a hash of a data block. Merkle trees can contain two children per node due to their two-fold branching factor. A protocol is a set of guidelines or a language that various entities can use to communicate or interact with one another. The Internet of Things (IoT) ecosystem is now used by household appliances, manufacturing equipment, vehicle parts, and other products. This environment has consequently had an impact on a wide range of locations, including households, car manufacturers, and hospitals, leading to a sharp rise in the variety of connected devices. The Internet of Things has grown in popularity as an outcome. However, system architects and protocol designers have found it challenging to select the appropriate communication protocol for these items or devices in a particular IoT system. The two key components of an IoT system are bidirectional connectivity and security. 2. LITERATURE SURVEY Calabretta et al. [1] concentrate on MQTT, a message-based protocol for communication built on the MQTT protocol that has been designed for low-power sensors. It utilizes the publish-subscribe model. Before anything else, we'll go over some of the standard security precautions and improvements listed in the There is a ton of information available for MQTT deployments. Then we offer a probable answer. alternative MQTT-based technique to protect particular topics The protocol AugPAKE was created by AugPAKE. Mukhandi et al. [2] study cyber-attacks might hamper the development and revision of the majority of ROS based robotic systems for Internet-based applications. It's crucial to recognize and reduce security vulnerabilities associated with applications that use ROS. Kertesz and Mishra [3]. Machine to Machine protocol is exhibited. The authors of this research Ingénierie des Systèmes d’Information Vol. 28, No. 2, April, 2023, pp. 419-424 Journal homepage: http://iieta.org/journals/isi 419