## 2 Literature Review  
[PERSON] et al. [11] established a new Decentralized Lightweight Group Key Management for Access Control (DLGKM-AC) from the IoT platform. According to a hierarchical design, collected of many Sub Key Distribution Centers (SKDCs) and one Key Distribution Center (KDC), the presented method improves the management of subscriber groups and improves the re-keying above on KDC. [PERSON] et al. [12] presented a new Blockchain-based decentralized key management (KM) protocol. It is resilient, dynamic, and scalable, and the presented technique utilizes the Blockchain (BC) for securely distributing the KM to many entities. [PERSON] et al. [13] examined a BC-based mutual authentication and key agreement procedure for edge computing-based smart grid schemes. The authors of [14] introduced a BC-based secure key management (BC-EKM) method. Primarily, the stake BC was generated dependent upon the hybrid sensor network. In addition, the author's proposal shows a secured cluster development technique and secured node movement technique for implementing key management, whereas staking BC as a trust machine exchanges the popular functions of BS.  
[PERSON] et al. [15] resolved these problems by presenting a new BC-based distributed key management architecture (BDKMA) with fog computing to reduce latency and multi-BCs performed from the cloud to achieve cross-domain access. The presented technique employs BC technology to satisfy the fine-grained auditability, maximum scalability, decentralization, extensibility necessities, and privacy-preserving rules for hierarchical access control from the IoT. A system operations approach with various authorization assignment modes and group access patterns is introduced to reinforce the extensibility. In [16], dependent upon (t,n) confidential sharing, a SIN-specific lightweight group key agreement protocol was presented for SD-SIN to ensure either applicability or security. In addition, assuming the extremely dynamic network topology, the authors also propose a group key-based secured handover authentication method for reducing the overhead. In [17], [PERSON] et al. examined the proposal of a decentralized and effectual key management system termed the DECENT method. During the threshold confidential sharing systems, the network node performs as a distributed trusted third party (TTP), so a threshold count of nodes cooperates for executing key management functions.  
[PERSON] et al. [18] present a DTLS (Datagram Transport Layer Security)-based SGC technique. The presented technique was scalable, lightweight, and robust against member compromise. In addition, the presented method verifies all the group members and is also appropriate for dynamic groups. [PERSON] et al. [19] present a novel method to offer FHE service, namely by utilizing garbled circuits. From a high-level perspective, garbled circuit and FHE both function by executing difficult computations on the ciphertext. The author determines a novel cryptographic primitive termed reusable garbled gate that develops in the region of garbled circuits; afterwards, dependent upon this novel primitive, the author depicts that it is very simple to construct FHE. [PERSON] et al. [20] presented a BC-IOTA sharding-based smart contract-centric group key agreement (GKA) for SGC in a huge VANET. In the elliptic curve decision Diffie-Hellman (ECDDH) and group-elliptic curve Diffie-Hellman (GECCDH), the presented method was established to be secure. [PERSON] et al. [21] concentrated on website page dataset security with the support of optimizer and encrypted approaches for Web of Things platforms. Primarily, the chosen queries from the webpage application can be introduced as a Discrete Bee Colony Optimizer (DBCO) technique. In addition, an effectual FHE encryption was presented in the case.