# Network Slicing for Beyond 5G Systems: An Overview of the Smart Port Use Case
## 1 Introduction  
Remote devices and wireless sensor networks have become a key part of our lives and the existing 4G network cannot meet the requirements of low latency and higher data rates. In recent years, the emergence of the Internet of things (IoT) has revolutionized almost every aspect of the communication field. Next-generation wireless networks make it possible for IoT devices to transform businesses by providing higher data rates and ultra-reliable low-latency communication (URLLC). Different technologies have already been developed for IoT networks, such as ZigBee, SigFox, and long range (LoRa) [1, 2]. However, these technologies are not compatible with the current cellular network, and there is a gap to be filled in order to address this challenge. The architecture of previous generations of mobile networks does not meet the diversity, scalability, and performance requirements because they are not flexible. The fifth generation (5G) network was designed to overcome these challenges, and can support three sets of use cases with diverse requirements in terms of data rate, reliability, latency, and massive connectivity. Services in 5G are classified into three main categories, namely:  
* Enhance Mobile Broadband (eMBB). * Massive Machine-Type Communications (mMTC). * Ultra-Reliable Low-Latency Communications (URLLC). Network slicing can provide answers to fulfill the above-mentioned specifications by partitioning or slicing the physical network into multiple logical networks according to their requirements [3]. Each logical network should have its attributes, which allows for thebetter utilization and allocation of the resources as compared to previous mobile networks. Logical networks provide flexibility and can be modified or operated dynamically to meet the requirements of the business segments according to service level agreement. All such logical sub-networks are treated as network slices, and a network slice consists of a set of network resources and functions. For instance, a logical sub-network can be customized to meet URLLC requirements. With network slicing, control and predictability can be achieved by reserving and isolating network resources and functions. From a security perspective, a logical sub-network can be connected to a virtual private network (VPN) by isolating it from the Internet. Due to the isolation of logical sub-networks, it will be easy to customize the customer needs according to the business model, as it was time-consuming over common infrastructure in the prior models. According to a GSMA report published in 2018 [3], NS will be the key technology of 5G opening the business opportunity worth USD 300 billion by 2025. It will allow the enterprise community to customize the services according to their own needs [3]. The concept of dividing the network into logical networks is not new as it has been used in VPN and virtual local area networks (VLANs). In 4G network slicing, dedicated core (DECOR) permits the implementation of multiple core networks within a common infrastructure [4]. Due to the limitations of evolved packet core (EPC) architecture, it does not offer flexibility and it also considers that the radio access network (RAN) is the same for all cases [5]. Different organizations in the past have contributed to fulfilling the requirements of vertical applications. The 5G Public-Private Partnership (5G-PPP) defines the relevant network resources for management and diversity with a five layer architecture [6]:  
* Service layer. * Infrastructure layer. * Business function layer. * Orchestration layer. * Network function layer. The objective of this paper is to analyze the recent developments in network slicing and present an approach by using ML algorithms in order to manage the resources more efficiently. In this paper, we have provided an overview of network slicing in 5G networks and present some enabling technology for network slicing in beyond 5G network.