Will SDN be part of 5G?

For many, this is no longer a valid question and the case is considered settled with SDN/NFV (Software Defined Networking/Network Function Virtualization) providing the inevitable innovation enablers solving many outstanding management issues regarding 5G. However, given the monumental task of softwarization of radio access network (RAN) while 5G is just around the corner and some companies have started unveiling their 5G equipment already, the concern is very realistic that we may only see some point solutions involving SDN technology instead of a fully SDN-enabled RAN. This survey paper identifies all important obstacles in the way and looks at the state of the art of the relevant solutions. This survey is different from the previous surveys on SDN-based RAN as it focuses on the salient problems and discusses solutions proposed within and outside SDN literature. Our main focus is on fronthaul, backward compatibility, supposedly disruptive nature of SDN deployment, business cases and monetization of SDN related upgrades, latency of general purpose processors (GPP), and additional security vulnerabilities, softwarization brings along to the RAN. We have also provided a summary of the architectural developments in SDN-based RAN landscape as not all work can be covered under the focused issues. This paper provides a comprehensive survey on the state of the art of SDN-based RAN and clearly points out the gaps in the technology.Comment: 33 pages, 10 figure

A cloudification methodology for multidimensional analysis: Implementation and application to a railway power simulator

Many scientific areas make extensive use of computer simulations to study complex real-world processes. These computations are typically very resource-intensive and present scalability issues as experiments get larger even in dedicated clusters, since these are limited by their own hardware resources. Cloud computing raises as an option to move forward into the ideal unlimited scalability by providing virtually infinite resources, yet applications must be adapted to this new paradigm. This process of converting and/or migrating an application and its data in order to make use of cloud computing is sometimes known as cloudifying the application. We propose a generalist cloudification method based in the MapReduce paradigm to migrate scientific simulations into the cloud to provide greater scalability. We analysed its viability by applying it to a real-world railway power consumption simulatior and running the resulting implementation on Hadoop YARN over Amazon EC2. Our tests show that the cloudified application is highly scalable and there is still a large margin to improve the theoretical model and its implementations, and also to extend it to a wider range of simulations. We also propose and evaluate a multidimensional analysis tool based on the cloudified application. It generates, executes and evaluates several experiments in parallel, for the same simulation kernel. The results we obtained indicate that out methodology is suitable for resource intensive simulations and multidimensional analysis, as it improves infrastructure’s utilization, efficiency and scalability when running many complex experiments.This work has been partially funded under the grant TIN2013-41350-P of the Spanish Ministry of Economics and Competitiveness, and the COST Action IC1305 "Network for Sustainable Ultrascale Computing Platforms" (NESUS)

Joint Optimization of Edge Computing Architectures and Radio Access Networks

Virtualized radio access network (vRAN) architectures and multiple-access edge computing (MEC) systems constitute two key solutions for the emerging Tactile Internet applications and the increasing mobile data traffic. Their efficient deployment, however, requires a careful design tailored to the available network resources and user demand. In this paper, we propose a novel modeling approach and a rigorous analytical framework, MEC-vRAN joint design problem (MvRAN), that minimizes vRAN costs and maximizes MEC performance. Our framework selects jointly the base-station function splits, the fronthaul routing paths, and the placement of MEC functions. We follow a data-driven evaluation method, using topologies of three operational networks and experiments with a typical face-recognition MEC service. Our results reveal that MvRAN achieves significant cost savings (up to 2.5 times) compared to non-optimized centralized RAN or decentralized RAN systems, and MEC pushes the vRAN functions to radio units and hence can increase substantially the network cost.Work supported by the EC under Grant No 761536 (5GTransformer) and by SFI under Grant No 17/CDA/4760

Algorithms for advance bandwidth reservation in media production networks

Media production generally requires many geographically distributed actors (e.g., production houses, broadcasters, advertisers) to exchange huge amounts of raw video and audio data. Traditional distribution techniques, such as dedicated point-to-point optical links, are highly inefficient in terms of installation time and cost. To improve efficiency, shared media production networks that connect all involved actors over a large geographical area, are currently being deployed. The traffic in such networks is often predictable, as the timing and bandwidth requirements of data transfers are generally known hours or even days in advance. As such, the use of advance bandwidth reservation (AR) can greatly increase resource utilization and cost efficiency. In this paper, we propose an Integer Linear Programming formulation of the bandwidth scheduling problem, which takes into account the specific characteristics of media production networks, is presented. Two novel optimization algorithms based on this model are thoroughly evaluated and compared by means of in-depth simulation results

Network Intelligence for Virtualized RAN Orchestration: The DAEMON Approach

Next-generation mobile networks will largely benefit from advances in softwarization and cloudification of network functions. However, fully exploiting the new potential of flexible network architectures in front of increasingly demanding service volumes and requirements calls for an extremely effective integration of Network Intelligence (NI) solutions into production infrastructures.While current standardization efforts towards embedding NI in beyond-5G and 6G systems are still in their infancy, the DAEMON project is developing technologies for a NI-native generation of mobile networks.In this paper, we present current evolutions proposed by DAEMON in terms of a general model for the representation of NI instances, which facilitates their synergic integration in network environments. We showcase the practical viability and advantages of the proposed approach with two state-of-the-art NI algorithms for vRAN orchestration implemented into an open-source data flow programming framework.This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement no.101017109 DAEMO

Hallintakerroksen suorituskyvyn vertailu virtualisoidussa tukiasemaohjaimessa

Mobile networks are in a middle of big changes. Requirements for scaling the networks while data and subscriber amounts are rapidly increasing make current network architectures too ossified. Current way of deploying mobile network with proprietary hardware and software of telecom equipment vendors is no longer sustainable. Telecom operators are having or will have profit problems with the current way. Fundamentals of building networks have to be changed. New paradigms from IT and internet world are coming also to mobile networks. Virtualized IT server hardware and cloud based service model together with latest concepts like SDN (Software Defined Networking) and NFV (Network Function Virtualization) are eagerly integrated as a parts of operator’s mobile network. Although most studies are concentrating on latest generations of mobile networks, mainly 4G, also older generations need to be part of the whole network portfolio. Future networks need to be transparent for users. In this scope, RAN (Radio Access Network) is in the biggest role being in the middle of the mobile user and the core network. This thesis studies the Single RAN concept from 2G BSC (Base Station Controller) point of view and what cloud, SDN and NFV would mean in that context. There were two main objectives for this study. First, based on literature, it was studied how telecom networks are technologically emerging from the current situation towards cloud service era. That was reflected to how all virtualization and cloud related technologies will possibly influence to the mobile network evolution and what high level steps are expected in the journey. As the study was focused in BSC, it was examined how the current architecture could be evolved to meet telecom industry requirements of the upcoming changes. Single (or common) radio access network is one part of the evolution and from the BSC point of view the scope was also to evaluate, what possibilities there are to merge the radio network controller functionality in 2G and 3G on top of a common virtualized hardware. Secondly two different initiatives of possibly needed steps in BSC part of the evolution were studied in practice. Many small steps will be needed and these experiments were just very small pieces in the entity. Those, however, indicated that a lot of studies, experiments and BSC architecture redesign will be needed.Mobiiliverkot ovat suurten muutosten keskellä. Nykyinen verkkoarkkitehtuuri on liian kankea vastatakseen verkon skaalautumisvaatimuksiin tiedon ja tilaajamäärien nopeasti kasvaessa. Nykyinen tapa kehittää mobiiliverkkoja verkkolaitetoimittajien suljetuilla laitteisto- ja ohjelmistoratkaisuilla ei enää ole kestävää. Nykyisellä tavalla mobiiliverkko-operaattoreilla on tai tulee olemaan kannattavuusongelmia. Mobiiliverkkojen rakentamisperiaatteiden täytyy muuttua. IT- ja internetmaailman uudet ajatusmallit tekevät tuloaan myös mobiiliverkkoihin. Virtualisoitu IT palvelinlaitteisto, pilvipalvelumallit yhdessä viimeisimpien käsitteiden, kuten SDN (Software Defined Networking) ja NFV (Network Function Virtualization) integroidaan innolla mobiiliverkkoihin. Vaikka useimmat tutkimukset keskittyvätkin viimeisiin mobiiliverkkoteknologioihin, kuten 4G, myös vanhempien teknologioiden täytyy olla osana laajempaa mobiiliverkkoa. Tässä tarkastelussa radioverkko on suurimassa roolissa mobiilikäyttäjän ja runkoverkon välissä. Tämä lopputyö tutki yhden radioverkon mallia 2G-tukiasemaohjaimen näkökulmasta, ja mitä nuo SDN ja NFV voisivat siinä yhteydessä tarkoittaa. Tässä lopputyössä oli kaksi pääkohdetta. Ensiksi, tutkittiin kirjallisuudesta, miten mobiiliverkot ovat teknisesti kehittymässä nykyisestä tilanteesta kohti pilvipalvelumallia. Tämä heijastuu siihen, miten kaikki virtualisointi ja pilvipalveluun liittyvät teknologiat tulevat mahdollisesti vaikuttamaan mobiiliverkkojen kehitykseen, ja mitä vaiheita kehitykseen liittyy. Koska lopputyö kohdistui 2G-tukiasemaohjaimeen, sen nykyistä arkkitehtuuria arvioitiin, miten se voisi kehittyä vastatakseen mobiiliverkkojen tuleviin vaatimuksiin. Yhteinen radioverkko on myös osa tätä kehitystä, siksi tuliaseman näkökulmasta pohdittiin myös, mitä vaihtoehtoja olisi yhdistää 2G- ja 3G-tukiasemaohjaimet toimivaksi yhteisessä virtualisoidussa laitteistossa. Toiseksi, tutkittiin käytännössä kahta mahdollista vaihetta, mitä saatetaan tarvita, kun tukiasemaohjainta virtualisoidaan. Nuo olivat pieniä vaiheita kokoisuuden kannalta mutta osoittivat, että tarvitaan paljon tutkimuksia, käytännön kokeiluja sekä tukiasemaohjaimen arkkitehtuurin uudelleen suunnittelua lopullisten tavoitteiden saavuttamiseksi

Design, implementation and experimental evaluation of a network-slicing aware mobile protocol stack

Mención Internacional en el título de doctorWith the arrival of new generation mobile networks, we currently observe a paradigm shift, where monolithic network functions running on dedicated hardware are now implemented as software pieces that can be virtualized on general purpose hardware platforms. This paradigm shift stands on the softwarization of network functions and the adoption of virtualization techniques. Network Function Virtualization (NFV) comprises softwarization of network elements and virtualization of these components. It brings multiple advantages: (i) Flexibility, allowing an easy management of the virtual network functions (VNFs) (deploy, start, stop or update); (ii) efficiency, resources can be adequately consumed due to the increased flexibility of the network infrastructure; and (iii) reduced costs, due to the ability of sharing hardware resources. To this end, multiple challenges must be addressed to effectively leverage of all these benefits. Network Function Virtualization envisioned the concept of virtual network, resulting in a key enabler of 5G networks flexibility, Network Slicing. This new paradigm represents a new way to operate mobile networks where the underlying infrastructure is "sliced" into logically separated networks that can be customized to the specific needs of the tenant. This approach also enables the ability of instantiate VNFs at different locations of the infrastructure, choosing their optimal placement based on parameters such as the requirements of the service traversing the slice or the available resources. This decision process is called orchestration and involves all the VNFs withing the same network slice. The orchestrator is the entity in charge of managing network slices. Hands-on experiments on network slicing are essential to understand its benefits and limits, and to validate the design and deployment choices. While some network slicing prototypes have been built for Radio Access Networks (RANs), leveraging on the wide availability of radio hardware and open-source software, there is no currently open-source suite for end-to-end network slicing available to the research community. Similarly, orchestration mechanisms must be evaluated as well to properly validate theoretical solutions addressing diverse aspects such as resource assignment or service composition. This thesis contributes on the study of the mobile networks evolution regarding its softwarization and cloudification. We identify software patterns for network function virtualization, including the definition of a novel mobile architecture that squeezes the virtualization architecture by splitting functionality in atomic functions. Then, we effectively design, implement and evaluate of an open-source network slicing implementation. Our results show a per-slice customization without paying the price in terms of performance, also providing a slicing implementation to the research community. Moreover, we propose a framework to flexibly re-orchestrate a virtualized network, allowing on-the-fly re-orchestration without disrupting ongoing services. This framework can greatly improve performance under changing conditions. We evaluate the resulting performance in a realistic network slicing setup, showing the feasibility and advantages of flexible re-orchestration. Lastly and following the required re-design of network functions envisioned during the study of the evolution of mobile networks, we present a novel pipeline architecture specifically engineered for 4G/5G Physical Layers virtualized over clouds. The proposed design follows two objectives, resiliency upon unpredictable computing and parallelization to increase efficiency in multi-core clouds. To this end, we employ techniques such as tight deadline control, jitter-absorbing buffers, predictive Hybrid Automatic Repeat Request, and congestion control. Our experimental results show that our cloud-native approach attains > 95% of the theoretical spectrum efficiency in hostile environments where stateof- the-art architectures collapse.This work has been supported by IMDEA Networks InstitutePrograma de Doctorado en Ingeniería Telemática por la Universidad Carlos III de MadridPresidente: Francisco Valera Pintor.- Secretario: Vincenzo Sciancalepore.- Vocal: Xenofon Fouka