# QoS Management and Flexible Traffic Detection Architecture for 5G Mobile Networks
## 1 Introduction  
In the last few decades, the growth in the number of mobile devices has increased mobile network traffic. The diversity of mobile applications such as Voice over IP (VoIP), web navigation, virtual reality, mobile TV, online games, etc., has also expanded the variety of QoS traffic requirements, which drives operators to improve their services. The fifth-generation (5G) of mobile networks is emerging with the purpose of satisfying those increasing demands by providing the highest QoS traffic characteristics such as ultra-low latency, ultra-reliable communication, high data rates, and high user mobility experience [1]. The existing 4G cellular technology developed by 3 GPP (Third Generation Partnership Project) [2] has significantly improved the characteristics of the previous cellular technology. However, 4G technology still has a number of limitations. The mobile logical entities of a 4G architecture are based on customized hardware configured and deployed in a static and cost-ineffective manner. The customization limits the elasticity of on-demand provisioning processes and the network innovation cycle. The control and data plane are coupled in the SGW--Serving Gateway--and in the PGW--Packet Data Network (PDN) Gateway, which increases complexity in network management possibilities and limits the network scalability. Additionally, the 4G mobile network data plane is centralized, so the traffic to and from the User Equipment (UE) always has to be routed through the PGW, which can be an inefficient routing alternative when the UEs involved in the communication are close to each other. To mitigate the weaknesses of the 4G architecture and to achieve the goals for the 5G cellular technology, the works in [3; 4; 5] have proposed the use of Network Function Virtualization (NFV) in the mobile network architecture. NFV [6; 7] technology allows the virtualization of the main entities of mobile architecture, which can be implemented as a software layer placed in less expensive commodity hardware or run in a cloud computing environment. NFV offers a flexible scaling alternative, which can be adapted in order to attend to variations of different demands and provide scaling in a distributed way, while increasing the robustness of the mobile network architecture. Another widely-proposed alternative to overcome the limitations of the 4G technology is the incorporation of SDN concepts [8; 9]. SDN architecture moves the control plane of mobile entities to central devices called controllers, which have a global view of the network and are responsible for managing the data plane of mobile networks. SDN offers a standard open interface to the communication between the controller and the data plane equipment, increasing the network flexibility and programmability and simplifying the data plane elements [10]. However, some disadvantages of a logically-centralized network control are the excessive dependence of every node on the controller, the large amount of information the controller must process, and the additional delay in the specific QoS flow creation, since the packet must wait for the controller response to be forwarded [11]. With SDN and QoS in mind, this paper proposes a new way to address the QoS traffic detection and the QoS traffic management, two of the principal requirements of next-generation 5G networks [12]. If the traffic with QoS requirements is faster and efficiently detected, it can be processed faster. Then, with the specialized QoS treatments, an optimal end-to-end QoS flow with the appropriate QoS characteristics can be created. The results show that the proposed logic is flexible and programmable, and it is applied very closely to the generated traffic (close to the UE), which increases the traffic engineering possibilities. The architecture proposed by our approach provides a network control application able to route traffic immediately with or without QoS requirements, eliminating the waiting times in the creation of new flows by the controller.