# Software Defined Networking Architecture for Energy Transaction in Smart Microgrid Systems
## 2 Related Work
It shifts the decision-making operation of the customer premises equipment (CPE) to the SDN controller. The northbound interface is the communication channel between the controller application (also referred to as SDN orchestrators) in the management plane and the controllers in the control plane. Finally,  
Figure 3: Layer view of an SDN architecture. the east\(-\)west interface allows inter-controller communication for functions that include controller load balancing and network scalability. Although SDN can meet some reliability and flexibility network requirements, it must still be optimized for the application and dynamic environment. For example, it is noteworthy to mention that SDN is not a mature solution according to [PERSON] et al. (2018). They confirm that particular challenges remain to be addressed, specifically for SDN-enabled wireless mobile backhaul networking. The challenges they identified apply to transactive energy and include optimized SDN southbound protocols, SDN controller solutions that meet the needs of the application, specific SDN and NFV integrated solutions, backhaul infrastructure sharing, multidimensional optimization policy, path calculation and information security, to name a few. [PERSON] et al. (2018) confirm that SDN enhances the network's resilience. However, the network is vulnerable to cyberattacks due to the flexible network integration of the SDN nodes and universal network visibility. They further explain that the ICT community is becoming more aware of growing attacks against SDN. Literature research found multiple examples of SDN designs in microgrid systems that focus on managing and controlling the microgrid. They prove that their SDN approach is an improvement to traditional ICT infrastructure; however, they do not consider the scalability of the SDN network, heterogeneous ICT infrastructure, or security vulnerabilities. Earlier SDN designs in smart microgrid systems (SMGSs) explored the SDN's advantages in managing the electrical grid conditions with a smart microgrid system. For example, [PERSON] et al. (2019) explored SDN to manage transmission and distribution networks and demonstrated the enhancement of the SMGS's resilience through SDN. Microgrid emergency control (MEC) through active fault management (AFM) is a function that benefits from an SDN architecture. [PERSON] et al. (2019) confirm that SDN provides continuous and reliable data transmission for detecting emergency conditions and reconnecting the microgrid to the primary grid. [PERSON] et al. (2021) also explore SDN to ensure a highly resilient AFM. Both papers do not include security enhancements or network resilience considerations in their designs. Another application of SDN in SMGSs is around advanced metering infrastructure (AMI), as explored by [PERSON] et al. (2020). They outline the advantages of an SDN architecture on applications such as security, load balancing, electrical system and network monitoring, and data routing. [PERSON] et al. (2020) also confirm that SDN is a suitable solution for supervisory control and data acquisition (SCADA) and AMI in SMGSs. Smart energy management applications in smart microgrid systems find multiple benefits with an SDN approach. [PERSON] et al. (2020) explore a software-defined machine-to-machine (SD-MZM) solution that provides benefits such as vendor-independent control, coordinated mobility control, fine-granularity resource allocation, and end-to-end QoS guarantee. There are literature papers that explore network solutions for transactive energy in particular. For example, the work of [PERSON] et al. (2020) explores an SDN network architecture for energy internet, which is like transactive energy. Their solution confirms that SDN is a suitable architecture for energy internet. However, their study differs from this paper in that it proposes an integrated hardware solution that combines the communication network and the electrical grid network into an intelligent energy controller (IEC).