Interoperability and Quality Assurance for Multi-Vendor LTE Network

The deployment of the LTE is picking up pace in many countries and these networks are deployed alongside the existing 2G/3G services. LTE/LTE-A networks offer higher data rates and reduced delay to the subscribers. Today's mobile networks consist of equipment from multiple vendors and they are called multiple vendor networks. Interoperability testing is important at initial network launch and during network expansion. This paper discusses a typical problem related to interoperability testing along with the test results and the issues faced during the testing. The test results discussed in the paper are obtained from three scenarios - before testing, during testing and after testing. The test results are used to study the impact on network performance. Apart from the interoperability testing, an outline of testing that focus on general network stability, the interworking capability of LTE with other technologies such as 2G and 3G and taxonomy for the generation of key performance indicators (KPIs) are also discussed

Benchmarking da eficiência dos algoritmos supervisionados de ML na classificação de tráfego NFV

A implementação de NFV permite melhorar a flexibilidade, a eficiência e a capacidade de gerenciamento das redes aproveitando a virtualização e as tecnologias da computação em nuvem para implantar redes informáticas. A implementação de gerenciamento autônomo e algoritmos supervisionados de Aprendizado de Máquinas (Machine Learning - ML) tornam-se uma estratégia chave para gerenciar esse tráfego oculto. Neste trabalho, nosso foco é a análise das características do tráfego em redes baseadas em NFV, ao mesmo tempo em que realizamos uma avaliação comparativa do comportamento dos algoritmos supervisionados de ML, isto é, J48, Naïve Bayes e Bayes Net na classificação de tráfego IP em relação à sua eficiência; considerando que essa eficiência está relacionada ao equilíbrio entre o tempo de resposta e precisão. Foram utilizados dois cenários de teste (um SDN baseado em NFV e um  LTE EPC baseado em NFV). Os resultados da avaliação comparativa revelam que os algoritmos Naïve Bayes e Bayes Net têm o melhor desempenho na classificação do tráfego. Em particular, seu desempenho corrobora um bom equilíbrio entre a precisão e o tempo de resposta, com valores de precisão superiores a 80% e 96%, respectivamente, para tempos inferiores a 1,5 segundos.La implementación de NFV permite mejorar la flexibilidad, eficiencia y gestión de redes al emplear tecnologías de virtualización y computación en la nube para desplegar nuevas redes de computadores. La implementación de procesos de gestión autónomos, junto con algoritmos de aprendizaje supervisado en la rama del conocimiento denominada aprendizaje de máquina (ML, Machine Learning) se ha convertido en una estrategia clave para gestionar tráfico en segundo plano. En este documento se presenta un proyecto de investigación que analiza características de tráfico de redes basadas en NFV al realizar una comparativa de la eficiencia (benchmarking) del comportamiento de algoritmos de aprendizaje supervisado para ML. Se analizaron los algoritmos J48, Naïve Bayes y Bayes Net y se analizó la clasificación de tráfico IP respecto a su eficiencia, la que está relacionada con la compensación entre el tiempo de respuesta y la precisión del algoritmo. Se emplearon dos escenarios de prueba (una SDN basada en NFV y un EPC LTE basado en NFV). Los resultados del benchmarking revelan que los algoritmos Naïve Bayes y Bayes Net obtuvieron mejor desempeño en la clasificación del tráfico. En particular, estos valores corroboran una adecuada compensación entre precisión y tiempo de respuesta, con valores de precisión mayores a 80% y 96%, respectivamente, en tiempos menores a 1.5 segundos.The implementation of NFV allows improving the flexibility, efficiency, and manageability of networks by leveraging virtualization and cloud computing technologies to deploy computer networks. The implementation of autonomic management and supervised algorithms from Machine Learning [ML] become a key strategy to manage this hidden traffic. In this work, we focus on analyzing the traffic features of NFV-based networks while performing a benchmarking of the behavior of supervised ML algorithms, namely J48, Naïve Bayes, and Bayes Net, in the IP traffic classification regarding their efficiency; considering that such an efficiency is related to the trade-off between time-response and precision. We used two test scenarios (an NFV-based SDN and an NFV-based LTE EPC). The benchmarking results reveal that the Naïve Bayes and Bayes Net algorithms achieve the best performance in traffic classification. In particular, their performance corroborates a good trade-off between precision and time-response, with precision values higher than 80 % and 96 %, respectively, in times less than 1,5 sec

The dark side of network functions virtualization: A perspective on the technological sustainability

The Network Functions Virtualization (NFV) paradigm is undoubtedly a key technological advancement in the Information and Communication Technology (ICT) community, especially for the upcoming 5G network design. While most of its promise is quite straightforward, the implied reduction of the power consumption/carbon footprint is still debatable, and not in line with the energy efficiency perspective forecasted by the ETSI NFV working group (WG). In this paper, we provide an estimate of the possible future requirements of this upcoming technology when deployed according to the virtual Evolved Packet Core (vEPC) use case specified by the ETSI NFV WG. Our estimation is based on real performance levels, certified by independent third-party laboratories, and datasheet values provided by existing commercial products for both the legacy and NFV network architectures, under different deployment scenarios. Obtained results show that a massive deployment of the current NFV technologies in the EPC may lead to a minimum increase of 106 % in the carbon footprint/energy consumption with respect to the Business As Usual (BAU) network solutions. Moreover, these values tend to increase at a very high pace when the most suitable software/hardware combination is not applied, or when packet processing latency is taken into account

Infrastructure sharing of 5G mobile core networks on an SDN/NFV platform

When looking towards the deployment of 5G network architectures, mobile network operators will continue to face many challenges. The number of customers is approaching maximum market penetration, the number of devices per customer is increasing, and the number of non-human operated devices estimated to approach towards the tens of billions, network operators have a formidable task ahead of them. The proliferation of cloud computing techniques has created a multitude of applications for network services deployments, and at the forefront is the adoption of Software-Defined Networking (SDN) and Network Functions Virtualisation (NFV). Mobile network operators (MNO) have the opportunity to leverage these technologies so that they can enable the delivery of traditional networking functionality in cloud environments. The benefit of this is reductions seen in the capital and operational expenditures of network infrastructure. When going for NFV, how a Virtualised Network Function (VNF) is designed, implemented, and placed over physical infrastructure can play a vital role on the performance metrics achieved by the network function. Not paying careful attention to this aspect could lead to the drastically reduced performance of network functions thus defeating the purpose of going for virtualisation solutions. The success of mobile network operators in the 5G arena will depend heavily on their ability to shift from their old operational models and embrace new technologies, design principles and innovation in both the business and technical aspects of the environment. The primary goal of this thesis is to design, implement and evaluate the viability of data centre and cloud network infrastructure sharing use case. More specifically, the core question addressed by this thesis is how virtualisation of network functions in a shared infrastructure environment can be achieved without adverse performance degradation. 5G should be operational with high penetration beyond the year 2020 with data traffic rates increasing exponentially and the number of connected devices expected to surpass tens of billions. Requirements for 5G mobile networks include higher flexibility, scalability, cost effectiveness and energy efficiency. Towards these goals, Software Defined Networking (SDN) and Network Functions Virtualisation have been adopted in recent proposals for future mobile networks architectures because they are considered critical technologies for 5G. A Shared Infrastructure Management Framework was designed and implemented for this purpose. This framework was further enhanced for performance optimisation of network functions and underlying physical infrastructure. The objective achieved was the identification of requirements for the design and development of an experimental testbed for future 5G mobile networks. This testbed deploys high performance virtualised network functions (VNFs) while catering for the infrastructure sharing use case of multiple network operators. The management and orchestration of the VNFs allow for automation, scalability, fault recovery, and security to be evaluated. The testbed developed is readily re-creatable and based on open-source software

Operational Aspects of Network Slicing in LTE and 5G Architectures

With the advances in cloud computing, the telecom operators are moving towards virtualization and cloud model. The future mobile networks are going to be deployed in the cloud with the help of Software Defined Networks (SDN) and Network Functions Virtualization (NFV) technologies. This thesis discusses various aspects related to prototyping and orchestration of slicing in LTE and 5G core networks using open-source technologies. The network slices are created in the user plane of the core network for differentiating the user traffic in terms of their QoS requirements. The Service Based Architecture (SBA) of 5G core is realized with the help of Google Remote Procedure Call (gRPC) as Service Based Interface (SBI) and Consul as Network Function Repository Function. On top of the setup created, the concept of Look-aside Load Balancing is used, to suit the 5G SBA and efficiently handle the incoming traffic load. With the Access and Mobility Management Function as a use case for load balancing, it is concluded that carefully chosen load balancing algorithms can significantly lessen the control plane latency when compared to simple random or round-robin schemes

Comunicaciones Móviles de Misión Crítica sobre Redes LTE

Mission Critical Communications (MCC) have been typically provided by proprietary radio technologies, but, in the last years, the interest to use commercial-off-the-shelf mobile technologies has increased. In this thesis, we explore the use of LTE to support MCC. We analyse the feasibility of LTE networks employing an experimental platform, PerformNetworks. To do so, we extend the testbed to increase the number of possible scenarios and the tooling available. After exploring the Key Performance Indicators (KPIs) of LTE, we propose different architectures to support the performance and functional requirements demanded by MCC. We have identified latency as one of the KPI to improve, so we have done several proposals to reduce it. These proposals follow the Mobile Edge Computing (MEC) paradigm, locating the services in what we called the fog, close to the base station to avoid the backhaul and transport networks. Our first proposal is the Fog Gateway, which is a MEC solution fully compatible with standard LTE networks that analyses the traffic coming from the base station to decide whether it has to be routed to the fog of processed normally by the SGW. Our second proposal is its natural evolution, the GTP Gateway that requires modifications on the base station. With this proposal, the base station will only transport over GTP the traffic not going to the fog. Both proposals have been validated by providing emulated scenarios, and, in the case of the Fog Gateway, also with the implementation of different prototypes, proving its compatibility with standard LTE network and its performance. The gateways can reduce drastically the end-to-end latency, as they avoid the time consumed by the backhaul and transport networks, with a very low trade-off

OpenEPC Integration within 5GTN as an NFV proof of concept

Abstract. Gone are the days, when a hardware is changed on every malfunctioning and the whole operation either stays down or load on the replacing hardware becomes too much which ultimately compromises the QoS. The IT industry is mature enough to tackle problems regarding scalability, space utilization, energy consumption, cost, agility and low availability. The expected throughput and network latency with 5G in the cellular Telecommunication Networks seems to be unachievable with the existing architecture and resources. Network Function Virtualization promises to merge IT and Telecommunications in such an efficient way that the expected results could be achieved no longer but sooner. The thesis work examines the compatibility and flexibility of a 3GPP virtual core network in a virtualization platform. The testbed is established on an LTE (Long Term Evolution) based network being already deployed and OpenEPC is added as virtual core network on it. The integration of OpenEPC in 5GTN (5TH Generation Test Network) is discussed in details in the thesis which will give an account of the possibility of implementing such a simulated vEPC (Virtual Evolved Packet Core) in a real network platform. The deployed setup is tested to check its feasibility and flexibility for a platform which could be used for NFV deployment in future. The monitoring of OpenEPC’s individual components while utilizing the major resources within them, forms the primary performance test. The CPU Load and Memory Utilization is tested on different CPU stress levels having a constant data traffic from actual UEs. At the completion of the thesis work, a consensus is built up based on the test results that the test setup can hold number of subscribers to a certain amount without any performance degradation. Moreover, the virtual core network throughput and network latency is also compared to the commercial LTE networks and theoretical maximum values on similar resources to check performance consistency OpenEPC must offer

Elastic Highly Available Cloud Computing

High availability and elasticity are two the cloud computing services technical features. Elasticity is a key feature of cloud computing where provisioning of resources is closely tied to the runtime demand. High availability assure that cloud applications are resilient to failures. Existing cloud solutions focus on providing both features at the level of the virtual resource through virtual machines by managing their restart, addition, and removal as needed. These existing solutions map applications to a specific design, which is not suitable for many applications especially virtualized telecommunication applications that are required to meet carrier grade standards. Carrier grade applications typically rely on the underlying platform to manage their availability by monitoring heartbeats, executing recoveries, and attempting repairs to bring the system back to normal. Migrating such applications to the cloud can be particularly challenging, especially if the elasticity policies target the application only, without considering the underlying platform contributing to its high availability (HA). In this thesis, a Network Function Virtualization (NFV) framework is introduced; the challenges and requirements of its use in mobile networks are discussed. In particular, an architecture for NFV framework entities in the virtual environment is proposed. In order to reduce signaling traffic congestion and achieve better performance, a criterion to bundle multiple functions of virtualized evolved packet-core in a single physical device or a group of adjacent devices is proposed. The analysis shows that the proposed grouping can reduce the network control traffic by 70 percent. Moreover, a comprehensive framework for the elasticity of highly available applications that considers the elastic deployment of the platform and the HA placement of the application’s components is proposed. The approach is applied to an internet protocol multimedia subsystem (IMS) application and demonstrate how, within a matter of seconds, the IMS application can be scaled up while maintaining its HA status

Coverage measurements of NB-IoT technology

Abstract. The narrowband internet of things (NB-IoT) is a cellular radio access technology that provides seamless connectivity to wireless IoT devices with low latency, low power consumption, and long-range coverage. For long-range coverage, NB-IoT offers a coverage enhancement (CE) mechanism that is achieved by repeating the transmission of signals. Good network coverage is essential to reduce the battery usage and power consumption of IoT devices, while poor network coverage increases the number of repetitions in transmission, which causes high power consumption of IoT devices. The primary objective of this work is to determine the network coverage of NB-IoT technology under the University of Oulu’s 5G test network (5GTN) base station. In this thesis work, measurement results on key performance indicators such as reference signal received power (RSRP), reference signal received quality (RSRQ), received signal strength indicator (RSSI), and signal to noise plus interference (SINR) have been reported. The goal of the measurement is to find out the NB-IoT signal strength at different locations, which are served by the 5GTN cells configured with different parameters, e.g., Tx power levels, antenna tilt angles. The signal strength of NB-IoT technology has been measured at different places under the 5GTN base station in Oulu, Finland. Drive tests have been conducted to measure the signal strength of NB-IoT technology by using the Quectel BG96 module, Qualcomm kDC-5737 dongle and Keysight Nemo Outdoor software. The results have shown the values of RSRP, RSRQ, RSSI, and SINR at different locations within several kilometres of the 5GTN base stations. These values indicate the performance of the network and are used to assess the performance of network services to the end-users. In this work, the overall performance of the network has been checked to verify if network performance meets good signal levels and good network coverage. Relevant details of the NB-IoT technology, the theory behind the signal coverage and comparisons with the measurement results have also been discussed to check the relevance of the measurement results