# An Efficient Framework for Securing the Smart City Communication Networks
## 2 Related Work
### Literature Review  
The integration of information and communication technologies in numerous application domains, such as transportation, academics, industries, medicine, and energy, has a significantly positive impact on society; however, systems' inability to cope with vulnerable attacks and loss of confidentiality, integrity, and authenticity has stymied this integration [11]. All application domains with communication infrastructure are vulnerable to cyber attacks, with the smart city being the most serious and vulnerable. Sensing, communication, control, and actuation systems work together to enable bi-directional pervasive communication for a variety of applications, including monitoring real-time energy consumption, providing real-time information to consumers, smart monitoring and tracking, control system commands, and more. One of the most essential roles of SCADA systems for remotely monitoring the grid's physical processes is power state system estimation [12]. The power system model and telemetered data help provide the best potential state of the system and can aid in ensuring appropriate power station performance through various applications. Because the system's state is based on a power state system estimation, a value that is invalid, corrupt, or deceptive as a result of a vulnerable attack might cause the system's state, management, and analysis to be diverted. Due to the risk to business-critical information, the bi-directional flow of information has generated a number of security and privacy issues; as a result, an efficient strategy is necessary to reduce complexity, computational cost, and processing time for immediate communication [13]. Although a large amount of research has been conducted in the realm of traditional cyber security, many approaches do not effectively meet the security requirements of grid systems. The following are some of the restrictions:  
* Lifespan of grid systems;
* Proprietary system's dependency;
* Remotely located resources;
* Lack of physical protection;
* Limited computational resources. The need of key management has been acknowledged in relation to advanced metering infrastructure, but no plan to combat threats has been proposed [14]. In the context of AMI, a key management system (KMS) for unicast, multicast, and broadcast transmission has been developed to improve efficiency, key storage, computation, and administration of keys with forward and backward security based on key graphs [15]. The authors have taken into account key creation and key freshness, authentication and integrity, and forward and backward security, but they have left out the process of key distribution, key destruction, key renewal/revocation, and the node replacement phase. Furthermore, because storage costs have become a concern, SELINDA has been proposed as a key establishment and data collection protocol to allow power operators to initiate shared keys with various measurement devices through an untrusted data relaying data collector unit [16]. In order to assure security during data collection, the data collector unit was not deemed to hold any key established between the power operator and measuring devices. Because the power operator controls all public keys for all measuring devices, unauthorized access or a little breach can put the entire system at risk. Furthermore, untrusted data replay nodes can expose data to a man-in-the-middle attack. The authors of [17] investigated a trust anchor so that a data collector and a device may do mutual authentication and key establishment. The suggested technique considers man-in-the-middle and replay attacks and is based on the public key and Needham-Schroeder authentication protocol. The key benefit of this method is that it reflects high levels of security, fault tolerance, and accessibility [18]. However, the complexity of resource constraint nodes in a smart grid is great due to the integration of both PKI and trustworthy anchors.