Softwarization of Radio and Wireless Networks

Ingrid Moerman, Spilios Giannoulis, Eli De Poorter, and Xianjun Jiao, imec – Ghent University

 

While SDR and SDN initially were parallel evolutions happening in isolated research communities, several European projects, more specifically the H2020 projects WiSHFUL, eWINE and ORCA are currently developing enablers to bridge the gap between SDR and SDN. These projects offer advanced software and hardware platforms in open state-of-the-art large-scale wireless test facilities that can be used and further extended by academic researchers and wireless developers.

Motivation

During the past decades we have witnessed the explosive emergence of wireless technologies and standards, covering different ranges and different licensed and unlicensed spectral bands.

Some trends observed are (1) the ever-increasing number and diversity of wireless devices (2) running applications that become more critical and bandwidth-hungry, and having very diverging QoS requirements, and (3) the presence of multiple heterogeneous wireless technologies, often integrated in the same device, sharing the same physical environment and in many cases also sharing the same spectral bands. Unfortunately, as the wireless radio spectrum is a scarce resource, the available spectral bandwidth does not scale with the increasing bandwidth demands from wireless devices and applications. There is a hence a need to introduce new sophisticated techniques for accessing and sharing the wireless medium in a highly efficient manner.  Such techniques are expected to either improve the coordination within a given spectral band (horizontal spectrum sharing), or explore the possibilities of opportunistically using unused spectrum in underutilized and potentially licensed spectral bands (vertical spectrum sharing, also called dynamic spectrum sharing or DSS).

The problem

Wireless networks have become extremely complex systems that cannot be optimized anymore following traditional approaches such as design-time planning and simple one-size-fits-all configuration strategies after deployment. Instead there is an increasing need for more intelligent techniques, being cognitive radio networking solutions, that can monitor the dynamic behaviour of the network, for instance the dynamics of the wireless environment and the varying application demands, and based on that autonomously adapt the network and radio parameters to maximize network performance and QoS. In many cases different applications have to share the same wireless infrastructure and the same spectral bands, making it really challenging to meet the very diverging QoS requirements simultaneously. The basic control mechanisms that are provided today in wireless technologies are not adequate to deal at the same time with extreme (ultra-low latency, ultra-high throughput, ultra-high reliability) and diverging (low AND high data rate, time-critical AND non-time critical) communication needs.

Interesting evolutions

Interesting softwarisation evolutions are happening at different levels and enable sharing of wireless infrastructure and spectrum:

  • At the networking level Software-Defined Networking (SDN) decouples the network control and data plane forwarding functions, enabling directly programmable network control offering diverse network services to a variety of applications. Such an approach allows virtualizing a single physical network into multiple logical network domains, each domain serving a certain category of traffic flows in the most appropriate way.
  • At the radio level, we have observed the emergence of Software-Defined Radio (SDR). An SDR is a radio communication system where transceiver components that are typically implemented on hardware (in an ASIC) are instead implemented by means of software on a host computer, or an embedded system equipped with programmable hardware like ASIP or FPGA.

While SDR and SDN initially were parallel evolutions happening in isolated research communities, several European projects, more specifically the H2020 projects WiSHFUL, eWINE and ORCA are currently developing enablers to bridge the gap between SDR and SDN. These projects offer advanced software and hardware platforms in open state-of-the-art large-scale wireless test facilities that can be used and further extended by academic researchers and wireless developers.

WiSHFUL project

The WiSHFUL project1 adopts the general idea of software defined networking (SDN), implemented in core IP networks, and applies it to the domain of heterogeneous wireless access networks. WiSHFUL offers several software platforms that comprise data plane and control plane functionality for advanced radio and network control supporting different wireless platforms (such as standard Linux and Wireless Mac Processor [1] for IEEE 802.11, Standard Contiki, TAISC [2] and GITAR [3] for IEEE 802.15.4, ip.access and Airspan for LTE, and Iris [4] for SDR). Although different wireless technologies and platforms can be very heterogeneous in terms of memory and processing capabilities, and supported operating systems, protocols and tools, the software platforms offered by the WiSHFUL project come with a unified, technology-agonistic interface, called UPI or Unified Programming Interface (see Figure 1) [5]:

  • The radio interface (UPI_R) consists of a set of functions that ensure uniform control of the radio hardware and lower MAC behaviour across heterogeneous devices. The lower MAC directly interacts with the radio hardware for radio transmission and reception, which involves time-critical operations.
  • The network interface (UPI_N) parallels the UPI_R with a set of functions that provides uniform control over the upper MAC and higher layer protocol behaviour across various devices. The upper MAC is responsible for inter-packet states, where inter-device coordination required, and is not time-critical.
  • The global interface (UPI_G) extends the reach of the control provided by both the UPI_R and the UPI_N across several devices in a coordinated manner.
  • The hierarchical control interface (UPI_HC) enables hierarchical control between control programs (inter-control communication and management).
  • The generic functions of UPI_R, UPI_N, and UPI_G are supported by Monitoring and Configuration Engines (MCEs) that contain and manage the platform specific implementations of UPIs. Naturally, the UPI_R and UPI_N are supported by a local MCE, while the UPI_G employs a global MCE.
  • Control Programs are user-defined software that implements the controlling logic for a wireless solution and makes use of the UPI_R and/or UPI_N for radio/network control. Local Control Programs use the local information and abilities of a single device, while Global Control Programs interact with a group of devices.

Figure 1

Figure 1: WiSHFUL conceptual architecture for flexible and unified radio and network control

Using the WiSHFUL software platforms, wireless network solution developers can focus on the network optimisation without the need to dig into complex hardware and software specifications for different technologies and platforms. They only have to write control program(s) that directly call the required UPI functions for monitoring and control.

eWINE project

The eWINE project2 extends the WiSHFUL software architecture with an intelligence toolbox (see Figure 2) for enabling intelligent network and radio control [6]. The connection between the WiSHFUL software architecture for radio and network control and the intelligence toolbox is made by the WiSHFUL UPIs. As the UPIs are unified abstractions that span across several wireless technology platforms, the components of the intelligence framework are generic. The Data Collection component is a generic software module that interacts with the WiSHFUL UPIs, to retrieve data about radio and network operation, and with the Application API to retrieve information about the application requirements. The Data Collection Component also implements aggregation functionality to reduce the amount of data or to change the representation of data. The Intelligence Composition module offers support for composing and configuring several algorithms available in the Intelligence Repository into a self-contained intelligence engine that uses the data provided by the Data Collection component and triggers configuration of radio and network through the Action component. The Action component translates the intelligence decisions taken by the Intelligence Composition component in a sequence of UPI calls. The eWINE intelligence toolbox offers a common set of tools that enable the realization of intelligent approaches using the algorithms from the repository. Together with the UPIs the toolbox enables reasoning about the current network state and applying actions to change the configuration of radio and network, hence realizing true cognitive networking.

Figure 2

Figure 2: the eWINE intelligence toolbox

ORCA project

The ORCA project3 (starting in January 2017) will accelerate flexible end-to-end experimental validation by making open and modular software and hardware architectures available meeting the requirements in terms of runtime latencies, throughput, and versatility, the latter referring to the (re)configuration and (re)programming capabilities. Such architectures smartly use novel flexible radio technology, more-specifically real-time Software Defined Radio (SDR) platforms. ORCA will fill the gap between 1) fast design cycle and high versatility, but high runtime latency (typically offered by a CPU environment), and 2) low runtime latency, but slow design cycle and low versatility (as offered by an ASIC), which is illustrated in Figure 3. ORCA will provide a wireless SDN architecture by adding a high degree of flexibility at the radio level to adapt wireless networks to the dynamic nature of today's applications [7]. The main target of ORCA is offering appropriate interfaces to integrate network functionality with RF, PHY and medium access functionality in SDR devices, providing a data, control and management plane at all levels (radio and network).

Figure 3

Figure 3: ORCA acceleration: filling the gap between high versatility §and low latency with real-time SDR

 

1http://www.wishful-project.eu/

2http://www.ewine-project.eu/

3http://www.orca-project.eu/

 

References

  1. I. Tinnirello, G. Bianchi, P. Gallo, D. Garlisi, F. Giuliano, F. Gringoli: Wireless MAC processors: Programming MAC protocols on commodity Hardware. IEEE INFOCOM 2012
  2. Bart Jooris, Jan Bauwens, Peter Ruckebusch, Peter De Valck, Christophe Van Praet, Ingrid Moerman, Eli De Poorter, "TAISC: a cross-platform MAC protocol compiler and execution engine", Computer Networks, Volume 107, Part 2, 9 October 2016, Pages 315–326
  3. Ruckebusch, P., De Poorter, E., Fortuna, C., & Moerman, I. (2016). GITAR: Generic extension for Internet-of-Things ARchitectures enabling dynamic updates of network and application modules. Ad Hoc Networks, Volume 36, Part 1, January 2016, Pages 127–151
  4. Sutton, P.D., Lotze, J., Lahlou, H., Fahmy, S.A., Nolan, K.E., Özgül, B., Rondeau, T.W., Noguera, J., Doyle, L.E., Iris: an architecture for cognitive radio networking testbeds, IEEE Communications Magazine, vol.48, no.9, pp.114-122, Sept. 2010
  5. Nicholas Kaminski, Ingrid Moerman, Spilios Giannoulis, Pierluigi Gallo, Anatolij Zubow, Robin Leblon, Ivan Seskar, Sunghyun Choi, and Jose de Rezende, "Unified Radio and Network Control Across Heterogeneous Hardware Platforms", ETSI Workshop on Future Radio Technologies - Air Interfaces, 27-28 January 2016, Sophia Antipolis, France
  6. Merima Kulin, Carolina Fortuna, Eli De Poorter, Dirk Deschrijver, Ingrid Moerman, “Data-Driven Design of Intelligent Wireless Networks: An Overview and Tutorial”, Sensors 2016, 16(6), 790
  7. Tarik Kazaz, Christophe Van Praet, Merima Kulin, Pieter Willemen, and Ingrid Moerman, "Hardware Accelerated SDR Platform for Adaptive Air Interfaces", ETSI Workshop on Future Radio Technologies - Air Interfaces, 27-28 January 2016, Sophia Antipolis, France

 


 

Ingrid MoermanIngrid Moerman received her degree in Electrical Engineering (1987) and the Ph.D. degree (1992) from the Ghent University, where she became a part-time professor in 2000. She is a staff member at IDLab, a core research group of imec with research activities embedded in Ghent University and University of Antwerp. Ingrid Moerman is coordinating the research activities on mobile and wireless networking, and she is leading a research team of about 30 members at IDLab-Ghent University. Her main research interests include: Internet of Things, Low Power Wide Area Networks (LPWAN), High-density wireless access networks, collaborative and cooperative networks, intelligent cognitive radio networks, real-time software defined radio, flexible hardware/software architectures for radio/network control and management, and experimentally-supported research. Ingrid Moerman has a longstanding experience in running and coordinating national and EU research funded projects. At the European level, Ingrid Moerman is in particular very active in the Future Networks research area, where she has coordinated and is coordinating several FP7/H2020 projects (CREW, WiSHFUL, eWINE, ORCA) and participating in other projects (Fed4FIRE, FORGE, FLEX, Flex5Gware).

Ingrid Moerman is author or co-author of more than 700 publications in international journals or conference proceedings.

 

Spilios GiannoulisSpilios Giannoulis received his Ph.D. (2010) in the area of routing protocols for wireless mobile sensor networks. From 2001 until 2015 he has been a researcher involved in several E.U. and national R&D projects at Industrial systems Institute (ISI) and the Applied Electronics Laboratory (APEL), University of Patras, Greece. From 2005 until 2015, he was also lecturing at the Technological Educational Institute (TEI) of Patras, Greece. He is currently a postdoc researcher in the IDLab research group of imec, Ghent, Belgium involved in several EU projects in the area of reconfigurable wireless networks. His main research interests are in the fields of wireless networks, mobile ad-hoc networks, wireless sensor networks, focusing on flexible and adaptive MAC and routing protocols, QoS provisioning, cross-layer and power aware system architecture design, with relevant publications in more than 20 international conferences and journals.

 

Eli De PoorterEli De Poorter is a Professor at Ghent University. He received his master degree in Computer Science Engineering from Ghent University, Belgium, in 2006, his Ph.D. degree in 2011 at the Department of Information Technology at Ghent University and became a full-time professor at Internet and Data Lab research group (IDLab, www.IDLab.ugent.be) in 2015.  In addition to teaching several courses, he is involved in and/or research coordinator of multiple national and international projects related to future wireless networks. His main research interests include wireless network protocols, network architectures, wireless sensor and ad hoc networks, future internet, self-learning networks and next-generation network architectures. He is part of the program committee of several conferences and is the author or co-author of more than 90 papers published in international journals or in the proceedings of international conferences. He is also the creator of the patented IDRA architecture, a flexible communication framework for heterogeneous networked devices.

 

Xianjun JiaoXianjun Jiao received his bachelor degree in Electrical Engineering from Nankai University in 2001 and Ph.D. degree on communications and information system from Peking University in 2006. After his studies, he worked in industrial research institutes and product teams in the domain of wireless technology, such as Radio System Lab of Nokia Research Center (senior researcher), devices department of Microsoft (senior researcher) and Wireless Software Engineering department of Apple (RF software engineer). In 2016, he joined IDLab, a core research group of imec with research activities embedded in Ghent University and University of Antwerp. He is working as postdoc researcher at Ghent University on flexible real-time SDR platform. His main interests are SDR and parallel/heterogeneous computation in wireless communications. On his research track, 20+ international patents and papers have been authored/published.

 

Editor:

Noel CrespiProf. Noël Crespi holds Masters degrees from the Universities of Orsay (Paris 11) and Kent (UK), a diplome d’ingénieur from Telecom ParisTech, a Ph.D and an Habilitation from Paris VI University (Paris-Sorbonne). From 1993 he worked at CLIP, Bouygues Telecom and then at Orange Labs in 1995. He took leading roles in the creation of new services with the successful conception and launch of Orange prepaid service, and in standardisation (from rapporteurship of IN standard to coordination of all mobile standards activities for Orange). In 1999, he joined Nortel Networks as telephony program manager, architecting core network products for EMEA region. He joined Institut Mines-Telecom in 2002 and is currently professor and Program Director, leading the Service Architecture Lab. He coordinates the standardisation activities for Institut Mines-Telecom at ITU-T, ETSI and 3GPP. He is also an adjunct professor at KAIST, an affiliate professor at Concordia University, and is on the 4-person Scientific Advisory Board of FTW (Austria). He is the scientific director the French-Korean laboratory ILLUMINE. His current research interests are in Service Architectures, Services Webification, Social Networks, and Internet of Things/Services.

http://noelcrespi.wp.tem-tsp.eu/

 



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IEEE Softwarization eNewsletter Editorial Board

Laurent Ciavaglia, Editor-in-Chief
Francesco Benedetto
Korhan Cengiz
Noel Crespi
Neil Davies
Eliezer Dekel
Eileen Healy
Chris Hrivnak
Atta ur Rehman Khan
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