Cloudified mobile networks are expected to deliver a multitude of services with reduced capital and operating expenses. A characteristic example is 5G networks serving several slices in parallel. Such mobile networks, therefore, need to ensure that the SLAs of customised end-to-end sliced services are met. This requires monitoring the resource usage and characteristics of data flows at the virtualised network core, as well as tracking the performance of the radio interfaces and UEs. A centralised monitoring architecture can not scale to support millions of UEs though. This paper, proposes a 2-stage distributed telemetry framework in which UEs act as early warning sensors. After UEs flag an anomaly, a ML model is activated, at network controller, to attribute the cause of the anomaly. The framework achieves 85% F1-score in detecting anomalies caused by different bottlenecks, and an overall 89% F1-score in attributing these bottlenecks. This accuracy of our distributed framework is similar to that of a centralised monitoring system, but with no overhead of transmitting UE-based telemetry data to the centralised controller. The study also finds that passive in-band network telemetry has the potential to replace active monitoring and can further reduce the overhead of a network monitoring system.

Network Function Virtualization is a key enabler to building future mobile networks in a flexible and cost-efficient way. Such a network is expected to manage and maintain itself with least human intervention. With early deployments of the fifth generation of mobile technologies – 5G – around the world, setting up 4G/5G experimental infrastructures is necessary to optimally design Self-Organising Networks (SON). In this demo, we present a custom small-scale 4G/5G testbed. As a step towards self-healing, the testbed integrates four Programming Protocol-independent Packet Processors (P4) virtual switches, that are placed along interfaces between different components of transport and core network. This demo not only shows the administration and monitoring of the Evolved Packet Core (EPC) VNF components, using Open Source MANO, but also as a proof of concept for the potential of P4-based telemetry in detecting anomalous behaviour of the mobile network, such as a congestion in the transport part.

Open Source MANO is a helpful tool to manage and orchestrate the instantiation of core network setups, like Network Service (NS) instances of our SimulaMet OpenAirInterface Virtual Network Function (VNF) for Enhanced Packet Cores (EPC). We furthermore extended our NS with VNF instances of Programming Protocol-independent Packet Processors (P4) switches, in order to allow for in-band telemetry. With in-band telemetry, it is possible to flexibly add, process, and remove telemetry information to traffic within the packet core, in order to allow for fine-granular evaluation of the system performance and the users' experienced quality of service. In our presentation and demo, we would like to provide an overview of our ongoing work on P4-based in-band telemetry in an OSM-orchestrated 4G core, which is used for detecting performance problems and anomalies in the network based on machine learning. We would furthermore like to demonstrate the details of our setup to the audience in a live demo.

The SimulaMet OpenAirInterface VNF provides an OpenAirInterface-based Enhanced Packet Core (EPC), with separate VDUs for HSS, MME, SPGW-C and SPGW-U. To allow for advanced in-band telemetry, we have extended this VNF to add switches with Programming Protocol-independent Packet Processors (P4) to all relevant virtual links inside the EPC. P4 allows full programability of the packet forwarding behaviour, and especially allows to extend packets with additional information for in-band telemetry. This information can be read by other P4 instances to allow for fine-granular performance data collection. In this presentation and live demonstration, we would like show the solutions chosen to efficiently use OSM for handling our extended EPC, and in particular we would like to highlight the possibilities to perform P4-based in-band telemetry to evaluate the performance of the mobile network. Finally, we would also like to show the audience a live demo of our testbed setup with telemetry collection.

The SimulaMet OpenAirInterface VNF is a complex 4-VDU VNF, allowing its users to instantiate and maintain a tailor-made Enhanced Packet Core (EPC) for 4G/5G mobile broadband testbeds. The EPC components are directly built from their sources during instantiation, allowing to use customised versions according to the users' needs. A general overview has already been presented during the OSM Hackfest in March 2020. In this presentation and live demonstration, we would like to highlight the solutions chosen to efficiently use OSM for handling the instantiation process, provide telemetry, and to debug issues. That is, we particularly would like to present to the audience the lessons learned during the ongoing development. Finally, we would also like to show the audience a live demo of an OSM-managed 4G testbed setup with telemetry collection.