5G System Architecture Research Articles

An architecture for control plane slicing in beyond 5G networks

To accommodate various use cases with differing characteristics, the Fifth Generation (5G) mobile communications system intends to utilize network slicing. Network slicing enables the creation of multiple logical networks over a shared physical network infrastructure. While the problems such as resource allocation for multiple slices in mobile networks have been explored in considerable detail in the existing literature, the suitability of the existing mobile network architecture to support network slicing has not been analysed adequately. We think the existing 5G System (5GS) architecture suffers from certain limitations, such as a lack of slice isolation in its control plane. This work focuses on the future evolution of the Third Generation Partnership Project (3GPP) 5GS architecture from a slicing perspective, especially that of its control plane, addressing some of the limitations of the 3GPP 5GS architecture. We propose a new network architecture which enables efficient slicing in beyond 5G networks. The proposed architecture results in enhanced modularity and scalability of the control plane in sliced mobile networks. In addition, it also brings slice isolation to the control plane, which is not feasible in the existing 5G system. We also present a performance evaluation that confirms the improved performance and scalability of the proposed system viz-a-viz the existing 5G system.

End-to-end simulation environment for mobile edge computing

Performances analysis of resource management techniques and algorithms for edge computing is a crucial step that reveals the effectiveness of edge service placement and migration strategies in terms of delay and usage. To be able to gauge how different optimisations affect the end user quality of experience a holistic approach is needed, so that the end-to-end delay can be measured in a combined setup where the edge infrastructure is integrated in the 5G system architecture. For these purposes we put forward an open source workflow based on the integration of proven simulators as SUMO, OMNeT++ and CloudSim, that will provide the means to create large scale urban mobile simulation environments. This paper discusses the benefits and challenges of such an approach, and provides example results that showcase a few aspects of the potential end-to-end delay analysis by processing the gathered simulation output.

An architecture and performance evaluation framework for artificial intelligence solutions in beyond 5G radio access networks

The evolution of mobile communications towards beyond 5th-generation (B5G) networks is envisaged to incorporate high levels of network automation. Network automation requires the development of a network architecture that accommodates multiple solutions based on artificial intelligence (AI) and machine learning (ML). Consequently, integrating AI into the 5th-generation (5G) systems such that we could leverage the advantages of ML techniques to optimize and improve the networks is one challenging topic for B5G networks. Based on a review of 5G system architecture, the state-of-the-art candidate AI/ML techniques, and the progress of the state of the art, and the on AI/ML for 5G in standards we define an AI architecture and performance evaluation framework for the deployment of the AI/ML solution in B5G networks. The suggested framework proposes three AI architectures alternatives, a centralized, a completely decentralized and an hybrid AI architecture. More specifically, the framework identifies the logical AI functions, determines their mapping to the B5G radio access network architecture and analyses the associated deployment cost factors in terms of compute, communicate and store costs. The framework is evaluated based on a use case scenario for heterogeneous networks where it is shown that the deployment cost profiling is different for the different AI architecture alternatives, and that this cost should be considered for the deployment and selection of the AI/ML solution.

Blockchain-Enabled Applications in Next-Generation Wireless Systems: Challenges and Opportunities

Many emerging wireless applications are based on unique requirements such as edge data processing, distributed trust, and automation, which can be provided and enabled by blockchain technology through decentralization, transaction accountability, and smart contract-based automation. This article discusses opportunities and challenges of such blockchain-enabled wireless applications. First, blockchain technology and 5G system architecture are briefly reviewed. Then, an example wireless application use case is presented to illustrate the benefits that blockchain technology can bring to wireless applications. A set of pending research issues addressing some of the challenges faced by blockchain-enabled wireless applications is introduced. As a potential solution, a wireless blockchain middleware architecture (BlockWare) is proposed, based on a blockchain middleware layer connecting wireless applications and underlying blockchain infrastructure. The blockchain middleware layer interacts with various types of blockchain systems on behalf of different wireless applications. Thus, a wireless application does not need to implement complex blockchain functions, rather relying on the blockchain middleware layer and its services to leverage various underlying blockchain systems. This article also points out several research directions for future study, such as inter-blockchain interactions and interoperability, efficient blockchain transaction management, and blockchain-based messaging in future wireless systems such as 5G, beyond 5G, and 6G.

Radio resource management: approaches and implementations from 4G to 5G and beyond

Radio resource and its management is one of the key areas of research where technologies, infrastructure and challenges are rapidly changing as 5G system architecture demands a paradigm shift. The previous generation communication technologies require customizations and upgrades as 5G will remain inclusive for significantly long duration. Radio resource management (RRM) schemes that are evolved during LTE/LTE-A network environment period will remain relevant for 5G, however, these schemes must become more intelligent and adaptive for future as features and requirements of network and users will be diverse and highly demanding. In this paper, a comprehensive view is provided upon various aspects of RRM, its challenges and existing schemes. The existing RRM schemes are presented with their respective architecture which has significant impact on the approaches. The problem of RRM is multi-dimensional and different dimensions are presented with their respective solutions such as interference or energy management. In this paper study of legacy and state of the art RRM schemes is presented with their features and inefficiencies in the modern telecommunication era of heterogeneous, ultra-dense, very low latency and highly reliable mobile network. In addition to this various comparison among approaches and schemes are presented for analyzing the solutions. The need of RRM solution is critical and this paper aim is to outline the challenges, existing solutions and directions for research to find and develop smarter and more adaptive schemes for future.

Controlling Next-Generation Software-Defined RANs

Compared to previous mobile generations, the 5G system architecture offers more flexibility to fulfill a richer set of diverse requirements. Three system aspects play a major role here: support of network slicing, a split between the user plane and the control plane, and a service oriented control architecture. Emerging techniques of network softwarization such as software-defined networking are leveraged to provide this notion of flexibility manifested in a software-defined core network. However, in addition to the 5G core (5GC), analogous concepts could be applied to the next generation radio access network to sustain the required system performance. Driven by the increased attention that is currently paid to a software-defined radio access network, in this article, we propose the radio access network control function (RANCF) as an additional 5G control function. We define the main functionalities of RANCF, and propose interfaces and protocols for the interaction with 5GC functions. Exploiting network slicing as an example, we demonstrate how RANCF facilitates the slice selection and slice management procedure.

ATSC 3.0 Broadcast 5G Unicast Heterogeneous Network Converged Services Starting Release 16

In this paper, the ATSC 3.0 broadcast Radio Access Technology (RAT) is aligned with 3GPP 5G NR RAT in the context of 5G convergence starting in Release 16. The 5G system architecture release 16 includes a new 5G physical layer known as 5G NR “New Radio” and a “Cloud Native” 5G Core (5GC) using cloud computing. The 5GC is agnostic to the type of radio access technology used and is enabler of many types of convergence. A novel shared multi-tenant broadcast core network architecture designed to interwork with 5GC is discussed. With the 3GPP 5G NR unicast and Non-3GPP ATSC 3.0 broadcast synergistically aligned using methods of Release 16. This includes using 3GPP Access Traffic Steering, Switching, Splitting (ATSSS) and a multi-radio dual simultaneous connected User Equipment (UE). This aligns ATSC 3.0, the first forward looking (non-backward-compatible) native IP OFDM broadcast standard, with 3GPP LTE/5G unicast as a converged 5G vertical. The proposed method and architecture are orthogonal to LTE broadcast Release 16 and is synergistic to 5G NR mixed-mode multicast unicast in future.

5G Radio Access Network Architecture for Terrestrial Broadcast Services

The 3rd Generation Partnership Project (3GPP) has defined based on the Long Term Evolution (LTE) enhanced Multicast Broadcast Multimedia Service (eMBMS) a set of new features to support the distribution of Terrestrial Broadcast services in Release 14. On the other hand, a new 5th Generation (5G) system architecture and radio access technology, 5G New Radio (NR), are being standardised from Release 15 onwards, which so far have only focused on unicast connectivity. This may change in Release 17 given a new Work Item set to specify basic Radio Access Network (RAN) functionalities for the provision of multicast/broadcast communications for NR. This work initially excludes some of the functionalities originally supported for Terrestrial Broadcast services under LTE e.g. free to air, receive-only mode, large-area single frequency networks, etc. This paper proposes an enhanced Next Generation RAN architecture based on 3GPP Release 15 with a series of architectural and functional enhancements, to support an efficient, flexible and dynamic selection between unicast and multicast/broadcast transmission modes and also the delivery of Terrestrial Broadcast services. The paper elaborates on the Cloud-RAN based architecture and proposes new concepts such as the RAN Broadcast/Multicast Areas that allows a more flexible deployment in comparison to eMBMS. High-level assessment methodologies including complexity analysis and inspection are used to evaluate the feasibility of the proposed architecture design and compare it with the 3GPP architectural requirements.

Multipath transmission control protocol–based multi-access traffic steering solution for 5G multimedia-centric network: Design and testbed system implementation

Various technologies have been developed for the efficient use of the multiple radio access technologies resource at the radio access network level or other network levels to improve user service quality in mobile communication networks. In long-term evolution, mobile carriers are commercializing radio access network-level traffic aggregation technologies such as licensed-assisted access-long-term evolution, long-term evolution-unlicensed, and long-term evolution-wireless local area network aggregation, which use the multi-accesses of the 3rd Generation Partnership Project and WiFi, and the multipath transmission control protocol–based traffic aggregation technologies at the L3 network level. The standardization of 3rd Generation Partnership Project Release 16, which is scheduled to be completed by 2020, is under progress to support the traffic aggregation technology at the L3 network level through a multi-access 5G network. Multipath transmission control protocol is also considered as a traffic aggregation technology. However, it is difficult to apply the multipath transmission control protocol employment model used in long-term evolution to the 5G network structure as it is due to the change to a common core architecture that accommodates multiple radio access technologies through one common interface. Therefore, this article proposes an optimal 5G system architecture and a multipath transmission control protocol adaptation method to support the access traffic steering function based on multipath transmission control protocol in a 3rd Generation Partnership Project 5G mobile communication network. We have verified the development of the multipath transmission control protocol–based multi-access traffic steering technology by implementing the proposed solution in a commercial server on a testbed based on the 5G system standard of 3rd Generation Partnership Project Release 15. Furthermore, this article defines problems that occur when implementing the multipath transmission control protocol–based multi-access traffic steering system and proposes relevant solutions. Based on the implementation results, it is demonstrated that the proposed multipath transmission control protocol–based multi-access traffic steering system can perform traffic steering in the 3rd Generation Partnership Project 5G network.

SODALITE: SDN Wireless Backhauling for Dense 4G/5G Small Cell Networks

Dense deployments of small cells (SCs) are key to fulfill the capacity requirements of future 5G networks. However, two roadblocks to the adoption of SCs are: 1) the limited availability and the cost of sites with wired backhaul resources and 2) the complexity to manage a dense deployment of wireless backhaul nodes. Towards these challenges we propose SODALITE, a novel system that applies software-defined networking (SDN) to a wireless backhaul network. We present, how SODALITE can be integrated to 3GPP’s 4G and 5G architectures, and show the feasibility of SODALITE through LTE network testbed experiments. We substantiate the scalability of SODALITE through stochastic studies using real-life traffic traces from an LTE network and discuss the effects of cell densification and 5G system architecture on these studies. Further, a reliable backhauling solution for wireless links is introduced in SODALITE through SDN-enabled mechanisms that are capable of reconfiguring the data plane upon a link failure detection. Its reliability is shown through experiments on an LTE network testbed, and studied thoroughly via rigorous simulations and network emulator evaluations. As a result, we claim that SODALITE is a promising carrier-grade system to manage a wireless SC backhaul.

5G V2X System-Level Architecture of 5GCAR Project

One of the goals of the 5G Communication Automotive Research and innovation (5GCAR) project has been to evaluate and propose system architecture enhancements aiming at supporting the strict requirements of vehicle-to-everything (V2X) use cases. In this paper, we provide an overview of 3GPP 5G system architecture, which is used as a baseline architecture in the project, and we present the main architectural enhancements introduced by 5GCAR. The work of the project focused on the following categories: (i) end-to-end security, also including aspects of privacy; (ii) network orchestration and management; (iii) network procedures; (iv) edge computing enhancements; and (v) multi-connectivity cooperation. The enhancements introduced by 5GCAR to above-listed categories are discussed in this paper, while a more detailed analysis of some selected features is presented.

Software-Defined architecture for QoS-Aware IoT deployments in 5G systems

Internet of Things (IoT), a ubiquitous network of interconnected objects, harvests information from the environments, interacts with the physical world, and uses the existing Internet infrastructure to provide services for information transfer and emerging applications. However, the scalability and Internet access fundamentally challenge the realization of a wide range of IoT applications. Based on recent developments of 5G system architecture, namely SoftAir, this paper introduces a new software-defined platform that enables dynamic and flexible infrastructure for 5G IoT communication. A corresponding sum-rate analysis is also carried out via an optimization approach for efficient data transmissions. First, the SoftAir decouples control plane and data plane for a software-defined wireless architecture and enables effective coordination among remote radio heads (RRHs), equipped with millimeter-wave (mmWave) frontend, for IoT access. Next, by introducing an innovative design of software-defined gateways (SD-GWs) as local IoT controllers in SoftAir, the wide diversity of IoT applications and the heterogeneity of IoT devices are easily accommodated. These SD-GWs aggregate the traffic from heterogeneous IoT devices and perform protocol conversions between IoT networks and radio access networks. Moreover, a cross-domain optimization framework is proposed in this extended SoftAir architecture concerning both upstream and downstream communication, where the respective sum-rates are maximized and system-level constraints are guaranteed, including (i) quality-of-service requirements of IoT transmissions, (ii) total power limit of mmWave RRHs, and (iii) fronthaul network capacities. Simulation results validate the efficacy of our solutions, where the extended SoftAir solution surpasses existing IoT schemes in spectral efficiency and achieves optimal data rates for next-generation IoT communication.

Adaptive 5G Low-Latency Communication for Tactile InternEt Services

The tactile internet will enable a new range of capabilities to enable immersive remote operations and interactions with a physical world. Tactile internet use cases span over many fields, from remote operation of industrial applications in, e.g., hazardous environments, via remote-controlled driving in a fully automated intelligent transport system, to remote surgery where the unique expert skills can be delivered to different locations in the world. Fifth-generation (5G) communication will play a fundamental part in this tactile internet vision, as it will provide necessary capabilities for the demanding communication needs in terms of reliability and low latency, for operators or teleoperated systems that are connected wirelessly. This paper provides an overview of tactile internet services and haptic interactions and communication. The 5G functionality for ultrareliable and low-latency services is described in depth and it is shown how 5G new radio (NR) and the evolved long-term evolution (LTE) radio interface can achieve guaranteed low-latency wireless transmission. The costs for providing reliable and low-latency wireless transmission in terms of reduced spectral efficiency and coverage are discussed. The 5G system architecture with a software-based network design based on a distributed cloud platform is presented. It is shown how the 5G network is configured for tactile internet services via multidomain orchestration.

The 5G System Architecture

This article provides an introduction to the 3GPP 5G system architecture and highlights its key features and characteristics.

Quality of service provision and capacity expansion through extended‐DSA for 5G

Abstract5G systems are expected to advance on a number of aspects compared with current systems, for example, providing a 1000 times higher capacity, a much lower latency and improved quality of user experience. This paper presents the vision and approach followed by the H2020 project SPEED‐5G. The approach is based on densification of small cells, exploitation of Multi‐RAT, development of new resource management techniques and a more efficient use of spectrum. A novel 5G system architecture is proposed based on the Network Slicing paradigm, which enables a highly flexible, scalable and backwards compatible architecture. A core aspect is the definition of a new MAC layer that facilitates Multi‐RAT access and allows prioritising and allocating traffic across heterogeneous access technologies. Copyright © 2016 John Wiley & Sons, Ltd.