Advanced NFV Features Applied to Multimedia Real-Time Communications Use Case Ana Pol∗, Anton Roman∗, Panagiotis Trakadas†, Panagiotis Karkazis†, Evgenia Kapassa‡, Marios Touloupou‡, Dimosthenis Kyriazis‡, Juan L. de la Cruz§, Pol Alemany§, Ricard Vilalta§, Raul Munoz§ ∗Quobis, O Porrino, Spain, Email: [ana.pol,anton.roman]@quobis.com †Synelixis Solutions S.A. 157, Perissou, str., 14343, Athens, Greece, Email: [ptrak,pkarkazis]@synelixis.com ‡Department of Digital Systems, University of Piraeus, Piraeus, Greece, Email: [ekapassa, mtouloup,dimos]@unipi.gr §CTTC, Castelldefels, Spain, Email:[jdelacruz,palemany,rvilalta,rmunoz]@cttc.es Abstract— Real-time communications are services with very demanding requirements in terms of reliability and Quality of Service (QoS) that is not easy to be reached. 5G technologies provide tools and techniques that promise to overcome the current shortcomings and thus give the opportunity to service providers to offer better services to the end users. This paper aims at describing how an existing real-time communications service can leverage the innovative features offered by the SONATA Service Platform (SP), such as network slicing, automated monitoring management and Service Level Agreement (SLA) enforcement, to meet the challenging requirements of the service. In this paper, we especially focus on the specific mechanisms implemented to support different QoS profiles at network level and automatic scale in/out of the service depending on the system load. Keywords— Real-time communications, 5G technologies, QoS Enforcement, SLAs, Monitoring, Slicing I. INTRODUCTION While the 5G concept is still rather unclear in certain dimensions [1], the evolved 5G network will be, for sure, characterized by agile, resilient and converged network realization, based on one hand on the disruptive core and radio access technologies and on the other hand on the network softwarization context brought by Network Function Virtualization (NFV) and Software Defined Networking (SDN) technologies. In the network softwarization frontier, a handful of commercial as well as open source Management and Orchestration (MANO) platforms have emerged (e.g. OSM [2], ONAP [3], Cloudify [4], SONATA [5], OPNFV [6]), considered as suites of functionalities for the management and orchestration of virtual resources related to the instantiation of Network Services (NS) consisting of Virtual Network Functions (VNFs) and their real-time provisioning. These MANO platforms are expected to add value to operators by reducing costs and deployment time and simplifying the management of the VNF and NS throughout their lifecycle. By capitalizing on the implemented techniques of the 5G innovative concepts, these platforms are able to accommodate different types of services and deal with the complexity of the NS-specific requirements. SONATA platform is an open source MANO framework whose functionalities are currently extended under the scope of the 5GTANGO H2020 project [7], offering unique advantages and innovative features demanded by real use cases. In particular, those features include a) an automated network monitoring framework, b) novel policy and SLA management and c) implementation of network slicing. This paper describes and evaluates the implementation of a real-time application service on top of the SONATA (powered by 5GTANGO) service platform. The remaining of the paper is organized as follows. Section II presents the state of the art of this work, while Section III introduces the overall SONATA (powered by 5GTANGO) Service Platform. Section IV describe in detail then enhanced proposed features, specially focusing on the recently new- added features such as QoS and multi-WIM support. This section describes also the principles of SONATA (powered by 5GTANGO) Monitoring Manager as well as the insights of the realization of the SNMP solution that has been utilized in this pilot. Additionally, this section presents the role of the SLA Manager and how it enables the definition and enforcement of SLAs, as well as the Slice Manager which helps to meet the QoS requirements of the network service. Section V presents the corresponding real-time communications use case, while Section VI states the evaluation of the proposed architecture. Finally, in Section VII, we close up with ideas for future experiments and current study capabilities. II. STATE OF THE ART Active and advanced work has been conducted on multimedia real-time communications use cases implied in 5G-enabled network softwarization technologies. In this direction, there are several approaches and architectures enabling effective communication between IP Multimedia Subsystems (IMS) and Web Real-Time Communication (WebRTC) users. The authors in [8], introduced a novel architecture supporting WebRTC users for smart community services, and proposed an optimization model to design and allocate resources for such systems while ensuring the desired QoS level. Furthermore, worth mentioned is the work conducted in [9], where the authors presented an open-source platform enabling developers to create and deploy RTC applications with advanced media processing capabilities. For this, they introduced the concept of Media Pipeline which is in fact chains of interconnected media processing elements. Their approach was also based on ETSI NFV recommendations. Henceforth, another interesting work was introduced in [10]. In this paper, a set of three software architectures were introduced for efficient virtualization of IMS in different operator environments responding to the high-level requirements of the ETSI NFV use case for virtualizing operator core network functions. In addition, based on their experiments, they have successfully managed to simplify the deployment and runtime orchestration of such a virtual service on top of a cloud infrastructure. Not only that, but also in [11], an analysis of next generation network architectures enabling real time multimedia communications was conducted.