## 2 Background and Related Studies  
Smart healthcare, which is constituted from patient wearable IoT devices, encompasses various security vulnerabilities and susceptibilities, i.e., the authentication of patient wearable devices, data privacy, and preservation, etc. [14; 15; 16]. Authentication of multiple wearable devices in a network is a critical part of secure communication because it guarantees the users' identities. Even though many experts have worked in this field to alleviate the known vulnerabilities and threats, over time these authentication models become susceptible to external and internal threats as the adversaries continually try to tamper and hijack them. Therefore, this domain is still open to new authentication schemes that could help to promote the validation process with better communication attributes. In [17], a community identity-based authentication model was proposed for healthcare IoT networks to address the security concerns in these networks. In this model, an elliptical curve cryptographic (ECC) was performed primarily to produce erratic bio-cryptographic signals to assure the validation of legal devices with secure communication. The authors of [18], presented a certificate-less-based authentication model for wireless body area networks to fix the security solicitudes of these networks. The storage of patient health records over the Cloud provides various opportunities and challenges. Cloud-based access control models are more susceptible to security breaches and a secure access control system is needed for current PHR-based models, since a Cloud-based framework mostly works in an open and integrated environment. Due to these features, Cloud-based networks are more vulnerable to data loss, theft, and security attacks. A weak network security system is one of the most highlighted and explored problems which has directed IT researchers to explore more smart security directions and tools for the Cloud using medical health-related data. The digital healthcare industry has many reasons not to trust the Cloud environment, because it cannot provide complete access control to patient health records. The fog computing-based IoMT is currently a hot topic [7]. Previous research works have missed important security issues such as:  
1. Healthcare IoT devices send data to Cloud servers that are frequently unencrypted and open to manipulation and attack. As a result, sensitive patient information will likely be accessible. 2. To our knowledge, the need to identify IoMT medical devices, which leads to the verification and authentication of health data, is urgent, and it can be accomplished quickly using a blockchain in the FC-IoMT system. Servers at the network's edge should perform more detailed authentication and verification. 3. BAKMP-IoMT, the new IoMT key agreement technique for blockchain-accessible authentication, was designed by [PERSON] et al. [13]. Between the medical devices implanted and the personal server, BAKMP-IoMT provides a secure key management mechanism. [PERSON] et al. [16] presented a revolutionary anonymous Internet of Things authentication mechanism resistant to machine PUF attacks. [PERSON] et al. [14] developed a strategy to avoid interference with MitMs and prevent alarms from the remote health surveillance system. [PERSON] et al. [15] used a profound learning model with the deep convolutions neuronal network (CNN) and a short-term long-range memory network. The approach described by [PERSON] et al. [16] can achieve a Nash balance. It is also obtained theoretically from the algorithm's top time complexity and the number of MEC patients. Mobile-based healthcare system was proposed by [PERSON] et al. [17]. This is also called a record sharing framework using BC through an approach based on user-centric security to limit the access of unprivileged users and to enhance the privacy via a channel formation scheme. The issue in this approach is the computational cost due to the complex cryptographic mechanism. However, using a health technology blockchain, [PERSON] et al.