The swift uptake of sensors and the increasing demand of Wireless Sensor Network (WSN) applications and services create unmatched appeals for routing data packets on WSN infrastructure. In the era of Internet of Things (IoT), an immense number of sensing devices collect numerous sensor data over time for an extensive span of fields. For IoT-enabled devices routing through WSN, sensor nodes transmit confidential data to the gateway nodes via public channels. In such an environment, secured routing remains a serious issue that has to be addressed. To address this issue, in this work, a robust method using Mid Square Hash-based Bezier Authentication (MSH-BA) is designed to secure the routing for IoT-enabled WSNs. First, a Mid Square Hashing Data Collection algorithm is proposed to minimize the energy consumption through unique key generation. To minimize the running time of IoT sensor network, discrete registration is performed between user and gateway nodes. Finally, the proof of correctness of mutual authentication is performed using the Bezier Authentication method via progressive distance, therefore ensuring packet delivery ratio. The robust authentication method is analyzed comprehensively and compared against the similar authentication methods and the results showed that it is efficient and robust than earlier methods.