IEEE Communications Magazine • November 2017 114 0163-6804/17/$25.00 © 2017 IEEE ABSTRACT In the last few years, we have seen an expo- nential increase in the number of Internet-enabled devices, which has resulted in popularity of fog and cloud computing among end users. End users expect high data rates coupled with secure data access for various applications executed either at the edge (fog computing) or in the core network (cloud computing). However, the bidirectional data flow between the end users and the devic- es located at either the edge or core may cause congestion at the cloud data centers, which are used mainly for data storage and data analytics. The high mobility of devices (e.g., vehicles) may also pose additional challenges with respect to data availability and processing at the core data centers. Hence, there is a need to have most of the resources available at the edge of the net- work to ensure the smooth execution of end-user applications. Considering the challenges of future user demands, we present an architecture that integrates cloud and fog computing in the 5G environment that works in collaboration with the advanced technologies such as SDN and NFV with the NSC model. The NSC service model helps to automate the virtual resources by chain- ing in a series for fast computing in both com- puting technologies. The proposed architecture also supports data analytics and management with respect to device mobility. Moreover, we also compare the core and edge computing with respect to the type of hypervisors, virtualization, security, and node heterogeneity. By focusing on nodes’ heterogeneity at the edge or core in the 5G environment, we also present security chal- lenges and possible types of attacks on the data shared between diferent devices in the 5G envi- ronment. INTRODUCTION Cloud computing and the Internet of Things (IoT) have become popular with the exponential usage of smart devices in recent years. Cloud computing is a platform for data storage, analytics, visualiza- tion, and shared pools of resources located across the globe through which various services can be accessed from anywhere using the Internet. On the other hand, IoT provides connectivity to var- ious smart devices that can be used for compu- tation and storage. Each device (smart object) has its own unique IP address for communicating with the other devices. Compared to IoT, cloud computing has a centralized architecture in which various data service providers are used to reduce data warehousing costs while providing virtually unlimited storage space. In contrast, IoT is a dis- tributed architecture and acts as a data receiver with limited storage capacity. As per the CISCO report [1], by 2020, the IoT will be made up of nearly 50 billion devices con- nected to the Internet (from 500 million in 2003, 12.5 billion in 2010, and 25 billion in 2015). The massive amount of data generated from the IoT devices is stored at the cloud data centers (DCs), which exponentially increases the load on the network. Network congestion is a major chal- lenge for processing large amounts of data from different geo-distributed database repositories. The other issues related to data processing at the DCs include slow data rates, low bandwidth, high end-to-end latency, high cost, fault tolerance, and security. Due to these challenges, real-time data analytics on large amounts of data becomes a challenging task. To meet the requirements of higher capacity and higher data rates for most real-time business applications, fifth generation (5G) technology has emerged. To improve the performance of cloud DCs, a new infrastructure model called a cloudlet (cloud servers) has become popular. The cloudlet model makes the cloud DCs’ capabilities accessible at the edge of the mobile network, also known as mobile edge computing (MEC) or fog computing (FC), which is considered as the future evolution of cloud computing. To address the above chal- lenges, fifth generation (5G) technology works in collaboration with other promising technolo- gies such as- software-defned networking (SDN), network functions virtualization (NFV), network service chaining (NSC), and massive mutiple-input multiple output (MIMO) technology [2] in order to provide high quality of service (QoS) to smart objects. The NSC service model integrates SDN and NFV services in order to perform fast computa- tion of services in the 5G network with the help of different types of network and communicat- ing protocols. The types of network connectivity used by the NSC model includes cellular tech- Rajat Chaudhary, Neeraj Kumar, and Sherali Zeadally ADVANCES IN NETWORK SERVICES CHAIN The authors present an architecture that integrates cloud and fog computing in the 5G environment that works in collaboration with advanced technologies such as SDN and NFV with the NSC model. The NSC service model helps to automate the virtual resources by chaining in a series for fast computing in both computing tech- nologies. The proposed architecture also supports data analytics and man- agement with respect to device mobility. Rajat Chaudhary and Neeraj Kumar are with Thapar University; Sherali Zeadally is with the University of Kentucky. Digital Object Identifier: 10.1109/MCOM.2017.1700102 Network Service Chaining in Fog and Cloud Computing for the 5G Environment: Data Management and Security Challenges