2018
[11]
A. Elsts, X. Fafoutis, S. Duquennoy, G. Oikonomou, R. Piechocki, I. Craddock, "Temperature-Resilient Time Synchronization for the Internet of Things", IEEE Transactions on Industrial Informatics, IEEE, 14(5), pp. 2241-2250, 2018
@article{Elsts-2018-tii, title = {Temperature-Resilient Time Synchronization for the Internet of Things}, author = {Atis Elsts and Xenofon Fafoutis and Simon Duquennoy and George Oikonomou and Robert Piechocki and Ian Craddock}, journal = {IEEE Transactions on Industrial Informatics}, publisher = {IEEE}, doi = {10.1109/TII.2017.2778746}, pages = {2241-2250}, volume = {14}, number = {5}, year = {2018}, month = {May}, oa-url = {https://research-information.bristol.ac.uk/en/publications/temperatureresilient-time-synchronization-for-the-internet-of-things(429dd808-1364-40e3-9c88-085f68ab37c9).html}, gsid = {999822098705616907}, abstract = {Networks deployed in real-world conditions have to cope with dynamic, unpredictable environmental temperature changes. These changes affect the clock rate on network nodes, and can cause faster clock de-synchronization compared to situations where devices are operating under stable temperature conditions. Wireless network protocols such as Time-Slotted Channel Hopping (TSCH) from the IEEE 802.15.4-2015 standard are affected by this problem, since they require tight clock synchronization among all nodes for the network to remain operational. This paper proposes a method for autonomously compensating temperature-dependent clock rate changes. After a calibration stage, nodes continuously perform temperature measurements to compensate for clock drifts at run-time. The method is implemented on low-power IoT nodes and evaluated through experiments in a temperature chamber, indoor and outdoor environments, as well as with numerical simulations. The results show that applying the method reduces the maximum synchronization error more than 10 times. In this way, the method allows reduce the total energy spent for time synchronization, which is practically relevant concern for low data rate, low energy budget TSCH networks, especially those exposed to environments with changing temperature.} }
Networks deployed in real-world conditions have to cope with dynamic, unpredictable environmental temperature changes. These changes affect the clock rate on network nodes, and can cause faster clock de-synchronization compared to situations where devices are operating under stable temperature conditions. Wireless network protocols such as Time-Slotted Channel Hopping (TSCH) from the IEEE 802.15.4-2015 standard are affected by this problem, since they require tight clock synchronization among all nodes for the network to remain operational. This paper proposes a method for autonomously compensating temperature-dependent clock rate changes. After a calibration stage, nodes continuously perform temperature measurements to compensate for clock drifts at run-time. The method is implemented on low-power IoT nodes and evaluated through experiments in a temperature chamber, indoor and outdoor environments, as well as with numerical simulations. The results show that applying the method reduces the maximum synchronization error more than 10 times. In this way, the method allows reduce the total energy spent for time synchronization, which is practically relevant concern for low data rate, low energy budget TSCH networks, especially those exposed to environments with changing temperature.
[10]
X. Fafoutis, A. Elsts, G. Oikonomou, R. Piechocki, I. Craddock, "Adaptive Static Scheduling in IEEE 802.15.4 TSCH Networks", in Proc. IEEE WF-IoT, pp. 263-268, 2018
@INPROCEEDINGS{Fafoutis-2018-wfiot, author = {Xenofon Fafoutis and Atis Elsts and George Oikonomou and Robert Piechocki and Ian Craddock}, title = {Adaptive Static Scheduling in IEEE 802.15.4 TSCH Networks}, publisher = {IEEE}, booktitle = {Proc. IEEE WF-IoT}, month = feb, pages = {263-268}, year = {2018}, doi = {10.1109/WF-IoT.2018.8355114}, gsid = {12784464564427922876}, oa-url = {https://research-information.bristol.ac.uk/en/publications/adaptive-static-scheduling-in-ieee-802154-tsch-networks(bfafab3a-7f19-4ac6-80b3-b2090ce85a90).html}, abstract = {TSCH (Time-Slotted Channel Hopping) is a synchronous MAC (Medium Access Control) protocol, introduced with the recent amendments to the IEEE 802.15.4 standard. Due to its channel hopping nature, TSCH is a promising enabling technology for dependable IoT (Internet of Things) infrastructures that are deployed in environments that are prone to interference. In TSCH, medium access is orchestrated by a schedule that is distributed to all the nodes in the network. In this paper, we propose Adaptive Static Scheduling to improve the energy efficiency of TSCH networks. Adaptive Static Scheduling builds on top of static schedules and allows each pair of communicating nodes to adaptively activate a subset of their allocated slots, effectively reducing the idle listening overhead of unused slots. Moreover, the nodes can dynamically activate more slots when they need to support bursts of high traffic, without the need of redistributing new schedules. Simulation results demonstrate that Adaptive Static Scheduling outperforms static scheduling in dynamic environments, operating nearly as efficiently as an oracle with knowledge of the optimal schedule.}, }
TSCH (Time-Slotted Channel Hopping) is a synchronous MAC (Medium Access Control) protocol, introduced with the recent amendments to the IEEE 802.15.4 standard. Due to its channel hopping nature, TSCH is a promising enabling technology for dependable IoT (Internet of Things) infrastructures that are deployed in environments that are prone to interference. In TSCH, medium access is orchestrated by a schedule that is distributed to all the nodes in the network. In this paper, we propose Adaptive Static Scheduling to improve the energy efficiency of TSCH networks. Adaptive Static Scheduling builds on top of static schedules and allows each pair of communicating nodes to adaptively activate a subset of their allocated slots, effectively reducing the idle listening overhead of unused slots. Moreover, the nodes can dynamically activate more slots when they need to support bursts of high traffic, without the need of redistributing new schedules. Simulation results demonstrate that Adaptive Static Scheduling outperforms static scheduling in dynamic environments, operating nearly as efficiently as an oracle with knowledge of the optimal schedule.
[9]
A. Elsts, E. Mitskas, G. Oikonomou, "Distributed Ledger Technology and the Internet of Things: A Feasibility Study", in Proc. BlockSys, pp. 7-12, 2018
@inproceedings{Elsts-2018-blocksys, title = {Distributed Ledger Technology and the Internet of Things: A Feasibility Study}, author = {Atis Elsts and Efstathios Mitskas and George Oikonomou}, year = {2018}, month = {11}, day = {4}, doi = {10.1145/3282278.3282280}, language = {English}, pages = {7--12}, booktitle = {Proc. BlockSys}, oa-url = {https://research-information.bristol.ac.uk/en/publications/distributed-ledger-technology-and-the-internet-of-things-a-feasibility-study(e9dbecde-7089-41d5-9943-e028b9d40e6c).html}, gsid = {16052130940079673351}, doi = {10.1145/3282278.3282280}, publisher = {Association for Computing Machinery (ACM)}, abstract = {Distributed Ledger Technologies have promising applications in the Internet of Things. However, scalability and support for micropayments remain problems for blockchain-based applications, therefore other alternatives such as IOTA should be considered. This work reports on an experimental evaluation of IOTA on several different IoT platforms. We show that even though the communication overhead to join the IOTA network can be significantly reduced by adapting a proxy-based architecture, the computational overhead remains high. We conclude that IOTA is not currently suitable for battery-powered IoT devices.}, }
Distributed Ledger Technologies have promising applications in the Internet of Things. However, scalability and support for micropayments remain problems for blockchain-based applications, therefore other alternatives such as IOTA should be considered. This work reports on an experimental evaluation of IOTA on several different IoT platforms. We show that even though the communication overhead to join the IOTA network can be significantly reduced by adapting a proxy-based architecture, the computational overhead remains high. We conclude that IOTA is not currently suitable for battery-powered IoT devices.
[8]
@inproceedings{Fafoutis-2018-RealWSN, title = {On Predicting the Battery Lifetime of IoT Devices: Experiences from the SPHERE Deployments}, author = {Xenofon Fafoutis and Atis Elsts and Antonis Vafeas and George Oikonomou and Robert Piechocki}, year = {2018}, month = {11}, day = {4}, doi = {10.1145/3277883.3277892}, language = {English}, pages = {7--12}, booktitle = {Proc. RealWSN}, publisher = {Association for Computing Machinery (ACM)}, oa-url = {https://research-information.bristol.ac.uk/en/publications/on-predicting-the-battery-lifetime-of-iot-devices-experiences-from-the-sphere-deployments(05c0efb7-16c9-47fc-b0e1-7fe9dc6f21ec).html}, gsid = {10336648821840413740}, doi = {10.1145/3277883.3277892}, abstract = {One of the challenges of deploying IoT battery-powered sensing systems is managing the maintenance of batteries. To that end, practitioners often employ prediction techniques to approximate the battery lifetime of the deployed devices. Following a series of longterm residential deployments in the wild, this paper contrasts real-world battery lifetimes and discharge patterns against battery lifetime predictions that were conducted during the development of the deployed system. The comparison highlights the challenges of making battery lifetime predictions, in an attempt to motivate further research on the matter. Moreover, this paper summarises key lessons learned that could potentially accelerate future IoT deployments of similar scale and nature.}, }
One of the challenges of deploying IoT battery-powered sensing systems is managing the maintenance of batteries. To that end, practitioners often employ prediction techniques to approximate the battery lifetime of the deployed devices. Following a series of longterm residential deployments in the wild, this paper contrasts real-world battery lifetimes and discharge patterns against battery lifetime predictions that were conducted during the development of the deployed system. The comparison highlights the challenges of making battery lifetime predictions, in an attempt to motivate further research on the matter. Moreover, this paper summarises key lessons learned that could potentially accelerate future IoT deployments of similar scale and nature.
[7]
A. Vafeas, A. Elsts, J. Pope, X. Fafoutis, G. Oikonomou, R. Piechocki, I. Craddock, "Energy-Efficient, Noninvasive Water Flow Sensor", in Proc. SMARTCOMP, pp. 139-146, 2018
@INPROCEEDINGS{Vafeas-2018-smartcomp, title = {Energy-Efficient, Noninvasive Water Flow Sensor}, author = {Antonis Vafeas and Atis Elsts and James Pope and Xenofon Fafoutis and George Oikonomou and Robert Piechocki and Ian Craddock}, booktitle = {Proc. SMARTCOMP}, year = {2018}, pages = {139-146}, doi = {10.1109/SMARTCOMP.2018.00084}, gsid = {1340752008608334172}, abstract = {We are interested in hot and cold water flow detection in domestic kitchen and bathroom taps for smart home environments. Water flow monitoring is particularly valuable for long-term behavioural monitoring systems for health-related applications, as it enables the collection of long-term data on the hydration levels of the house residents, and it is associated with several activities of daily life, such as cooking and cleaning. This paper presents a water flow sensing device that is based on sensing the vibrations on the pipe when water is flowing through them. The proposed solution is noninvasive and energyefficient, as it does not require cutting the water pipes or altering the plumbing system, and consumes less then 2 µA in continuous operation. The proposed water flow sensor has been integrated to SPHERE, a sensing platform of non-medical sensors for healthcare monitoring and behavioural analytics in a home environment, and deployed to more than 15 residential properties.}, }
We are interested in hot and cold water flow detection in domestic kitchen and bathroom taps for smart home environments. Water flow monitoring is particularly valuable for long-term behavioural monitoring systems for health-related applications, as it enables the collection of long-term data on the hydration levels of the house residents, and it is associated with several activities of daily life, such as cooking and cleaning. This paper presents a water flow sensing device that is based on sensing the vibrations on the pipe when water is flowing through them. The proposed solution is noninvasive and energyefficient, as it does not require cutting the water pipes or altering the plumbing system, and consumes less then 2 µA in continuous operation. The proposed water flow sensor has been integrated to SPHERE, a sensing platform of non-medical sensors for healthcare monitoring and behavioural analytics in a home environment, and deployed to more than 15 residential properties.
[6]
J. Pope, A. Vafeas, A. Elsts, G. Oikonomou, R. Piechocki, I. Craddock, "An Accelerometer Lossless Compression Algorithm and Energy Analysis for IoT Devices", in Proc. WCNC Workshops, pp. 396-401, 2018
@INPROCEEDINGS{Pope-2018-wcnc, title = {An Accelerometer Lossless Compression Algorithm and Energy Analysis for IoT Devices}, author = {James Pope and Antonis Vafeas and Atis Elsts and George Oikonomou and Robert Piechocki and Ian Craddock}, year = {2018}, booktitle = {Proc. WCNC Workshops}, publisher = {IEEE}, pages = {396-401}, doi = {10.1109/WCNCW.2018.8368985}, gsid = {4137926603080687766}, oa-url = {https://research-information.bristol.ac.uk/en/publications/an-accelerometer-lossless-compression-algorithm-and-energy-analysis-for-iot-devices(ba9c4c1b-a085-429d-a5db-d8010736b6fc).html}, abstract = {The Internet of Things promises to enable numerous future applications spanning many domains, including health care, and is comprised of devices that are constrained in terms of computational and energy resources. A specific health care application is to ascertain patients' activity of daily living while at home using accelerometer data from non-invasive wearables. It is often necessary to store this data on the device to be retrieved later for analysis. However, the devices typically store far more data than can be transmitted with commonly used low power radios. To mitigate the problem, this paper proposes an energy efficient, lossless compression algorithm that uses an offline frequency distribution to create a symbol-code lookup table. Using an extensive set of data from a previous study, an analysis of the entropy of activities of daily living accelerometer data is presented. The compression algorithm is compared against this estimated entropy. Energy being critical for IoT devices, the trade-off between energy cost for compression versus energy saved during transmission is also analysed.}, }
The Internet of Things promises to enable numerous future applications spanning many domains, including health care, and is comprised of devices that are constrained in terms of computational and energy resources. A specific health care application is to ascertain patients' activity of daily living while at home using accelerometer data from non-invasive wearables. It is often necessary to store this data on the device to be retrieved later for analysis. However, the devices typically store far more data than can be transmitted with commonly used low power radios. To mitigate the problem, this paper proposes an energy efficient, lossless compression algorithm that uses an offline frequency distribution to create a symbol-code lookup table. Using an extensive set of data from a previous study, an analysis of the entropy of activities of daily living accelerometer data is presented. The compression algorithm is compared against this estimated entropy. Energy being critical for IoT devices, the trade-off between energy cost for compression versus energy saved during transmission is also analysed.
[5]
A. Peters, G. Oikonomou, G. Zervas, "In Compute/Memory Dynamic Packet/Circuit Switch Placement for Optically Disaggregated Data Centers", J. Opt. Commun. Netw., OSA, 10(7), pp. B164-B178, 2018
@article{Peters-2018-ofc, title = {In Compute/Memory Dynamic Packet/Circuit Switch Placement for Optically Disaggregated Data Centers}, author = {Adaranijo Peters and George Oikonomou and Georgios Zervas}, year = {2018}, journal = {J. Opt. Commun. Netw.}, publisher = {OSA}, volume = {10}, number = {7}, pages = {B164-B178}, doi = {10.1364/JOCN.10.00B164}, gsid = {14408439199561786844}, abstract = {Network function services on conventional hybrid data center (DC) architectures such as HELIOS are hard-wired and dedicated to specific network resources. This limits flexibility and performance to handle diverse traffic patterns. Furthermore, disaggregation of server resources has shown promising potential to improve resource utilization, which has been a limitation of conventional server-centric DCs. This paper presents a reconfigurable hybrid disaggregated DC (dRedBox) architecture that combines the concept of server resource disaggregation with cutting-edge software and electronic and optical technologies. The dRedBox architecture provides a remarkable amount of flexibility and connectivity through hardware-based multilayer network function service programmability. This allows for multilayer network services to be dynamically deployed at runtime to network resources and, in turn, handle diverse traffic patterns. Furthermore, this study proposes algorithms and strategies for selecting and deploying electronic packet switching and optical circuit switching function services to implement virtual machine network requests across dRedBox and conventional hybrid disaggregated architectures under different traffic patterns. Finally, the performance of the various strategies on the dRedBox and conventional hybrid disaggregated DC architectures is evaluated in terms of blocking probability, energy efficiency, network utilization, and cost. Extensive results show that, at 10\% blocking probability, dRedBox architecture achieves 100\% gain on VM placement and 92\% energy savings compared with conventional hybrid disaggregated architectures.}, }
Network function services on conventional hybrid data center (DC) architectures such as HELIOS are hard-wired and dedicated to specific network resources. This limits flexibility and performance to handle diverse traffic patterns. Furthermore, disaggregation of server resources has shown promising potential to improve resource utilization, which has been a limitation of conventional server-centric DCs. This paper presents a reconfigurable hybrid disaggregated DC (dRedBox) architecture that combines the concept of server resource disaggregation with cutting-edge software and electronic and optical technologies. The dRedBox architecture provides a remarkable amount of flexibility and connectivity through hardware-based multilayer network function service programmability. This allows for multilayer network services to be dynamically deployed at runtime to network resources and, in turn, handle diverse traffic patterns. Furthermore, this study proposes algorithms and strategies for selecting and deploying electronic packet switching and optical circuit switching function services to implement virtual machine network requests across dRedBox and conventional hybrid disaggregated architectures under different traffic patterns. Finally, the performance of the various strategies on the dRedBox and conventional hybrid disaggregated DC architectures is evaluated in terms of blocking probability, energy efficiency, network utilization, and cost. Extensive results show that, at 10\% blocking probability, dRedBox architecture achieves 100\% gain on VM placement and 92\% energy savings compared with conventional hybrid disaggregated architectures.
[4]
G. Margelis, X. Fafoutis, G. Oikonomou, R. Piechocki, T. Tryfonas, P. Thomas, "Efficient DCT-based Secret Key Generation for the Internet of Things", Ad Hoc Networks, Elsevier, 2018
@article{Margelis-2018-AdHoc, author = {George Margelis and Xenofon Fafoutis and George Oikonomou and Robert Piechocki and Theo Tryfonas and Paul Thomas}, title = {Efficient DCT-based Secret Key Generation for the Internet of Things}, journal = {Ad Hoc Networks}, publisher = {Elsevier}, year = {2018}, gsid = {5818991158831943032}, doi = {10.1016/j.adhoc.2018.08.014}, oa-url = {https://www.sciencedirect.com/science/article/pii/S1570870518305948}, abstract = {Internet of Things (IoT) Security is critical, and the most widely employed method to ensure robust confidentiality is cryptography. However, establishing cryptographically secure communication links between two transceivers requires the pre-agreement on some key, unknown to an external attacker. In recent years there has been growing interest in techniques that generate a shared random key through observation of the channel and its effects on the exchanged messages. In this work we present SKYGlow, a novel scheme for secret-key generation, designed for low-power IoT devices and tested on IEEE 802.15.4 transceivers. We first examine the practical upper bounds of the maximum length of the secret-key that can be generated by communicating IEEE 802.15.4 devices. We contrast that upper-bound with the current state-of-the-art, and elaborate on the workings of our proposed scheme. SKYGlow applies the Discreet Cosine Transform (DCT) on the Received Signal Strength (RSS) values of exchanged messages to reduce mismatches and increase correlation between the generated secret-bits. We validate the performance of our scheme on both outdoor and indoor scenarios, on the 2.4 GHz and 868 MHz ISM bands. Our experiments have resulted in the creation of 128 bit secret keys with only 65 packet exchanges and with an entropy of 0.9978 bits, making our scheme much more energy efficient compared with others in the existing literature. }, }
Internet of Things (IoT) Security is critical, and the most widely employed method to ensure robust confidentiality is cryptography. However, establishing cryptographically secure communication links between two transceivers requires the pre-agreement on some key, unknown to an external attacker. In recent years there has been growing interest in techniques that generate a shared random key through observation of the channel and its effects on the exchanged messages. In this work we present SKYGlow, a novel scheme for secret-key generation, designed for low-power IoT devices and tested on IEEE 802.15.4 transceivers. We first examine the practical upper bounds of the maximum length of the secret-key that can be generated by communicating IEEE 802.15.4 devices. We contrast that upper-bound with the current state-of-the-art, and elaborate on the workings of our proposed scheme. SKYGlow applies the Discreet Cosine Transform (DCT) on the Received Signal Strength (RSS) values of exchanged messages to reduce mismatches and increase correlation between the generated secret-bits. We validate the performance of our scheme on both outdoor and indoor scenarios, on the 2.4 GHz and 868 MHz ISM bands. Our experiments have resulted in the creation of 128 bit secret keys with only 65 packet exchanges and with an entropy of 0.9978 bits, making our scheme much more energy efficient compared with others in the existing literature.
[3]
X. Fafoutis, A. Elsts, G. Oikonomou, R. Piechocki, "SPHERE Deployment Manager: A Tool for Deploying IoT Sensor Networks at Large Scale", in Proc. AdHoc Now, ser. LNCS, 11104, pp. 307-318, 2018
@inproceedings{Fafoutis-2018-AdHocNow, title={SPHERE Deployment Manager: A Tool for Deploying IoT Sensor Networks at Large Scale}, author={Fafoutis, Xenofon and Elsts, Atis and Oikonomou, George and Piechocki, Robert}, booktitle={Proc. AdHoc Now}, pages={307--318}, year={2018}, gsid = {6516981089610036943}, doi = {10.1007/978-3-030-00247-3_27}, volume = {11104}, publisher = {Springer}, oa-url = {https://research-information.bristol.ac.uk/en/publications/sphere-deployment-manager(81e729f8-7f20-49af-b76c-43ad9dbe09e0).html}, series = {LNCS}, abstract = {Internet of Things (IoT) technology has the potential to revolutionise several domains of everyday life, including the healthcare sector. In order to reach its full potential, IoT technology needs to be evaluated in the real world, beyond controlled environments, such as laboratories and test-beds. SPHERE is an experimental sensing platform for healthcare in a residential environment. Unlike other similar smart home health systems, SPHERE is deployed in a large number of properties of volunteers. Based on our experiences and lessons learned from SPHERE’s large-scale deployments, this paper focuses on the challenge of effectively managing the sensor installation overhead, aiming at supporting our deployment technicians with achieving a satisfactory deployment throughput. In this context, this paper presents the SPHERE Deployment Manager: an open-source tool that facilitates the deployment of bespoke IoT networks by technicians that are not experts in IoT technology. We believe that the SPHERE Deployment Manager is a tool that can accelerate future IoT research deployments of similar nature and scale.}, }
Internet of Things (IoT) technology has the potential to revolutionise several domains of everyday life, including the healthcare sector. In order to reach its full potential, IoT technology needs to be evaluated in the real world, beyond controlled environments, such as laboratories and test-beds. SPHERE is an experimental sensing platform for healthcare in a residential environment. Unlike other similar smart home health systems, SPHERE is deployed in a large number of properties of volunteers. Based on our experiences and lessons learned from SPHERE’s large-scale deployments, this paper focuses on the challenge of effectively managing the sensor installation overhead, aiming at supporting our deployment technicians with achieving a satisfactory deployment throughput. In this context, this paper presents the SPHERE Deployment Manager: an open-source tool that facilitates the deployment of bespoke IoT networks by technicians that are not experts in IoT technology. We believe that the SPHERE Deployment Manager is a tool that can accelerate future IoT research deployments of similar nature and scale.
[2]
M. Dilmore, A. Doufexi, G. Oikonomou, "Analysing Interface Bonding in 5G WLANs", in Proc. CAMAD, 2018
@INPROCEEDINGS{Dilmore-2018-camad, title = {Analysing Interface Bonding in 5G WLANs}, author = {Michael Dilmore and Angela Doufexi and George Oikonomou}, year = {2018}, booktitle = {Proc. CAMAD}, publisher = {IEEE}, doi = {10.1109/CAMAD.2018.8514934}, abstract = {This work proposes a simple analytical model for interface bonding in 5G WLANs at the 2.4 GHz and 60 GHz ISM bands. Based on previous analysis of the IEEE 802.11 DCF by Bianchi and Chatzimisios, an expression for the predicted throughput of the bonded interface is given as a function of the number of competing wireless nodes in each network.The model is implemented and validated in MatLab using the Monte Carlo method. When applied to a practical interface bonding scenario, the model results suggest a practical limit of fifteen 2.4 GHz nodes when bonded with a 60 GHz interface, above which the resulting compound throughput is less than that of a single 60 GHz interface.}, }
This work proposes a simple analytical model for interface bonding in 5G WLANs at the 2.4 GHz and 60 GHz ISM bands. Based on previous analysis of the IEEE 802.11 DCF by Bianchi and Chatzimisios, an expression for the predicted throughput of the bonded interface is given as a function of the number of competing wireless nodes in each network.The model is implemented and validated in MatLab using the Monte Carlo method. When applied to a practical interface bonding scenario, the model results suggest a practical limit of fifteen 2.4 GHz nodes when bonded with a 60 GHz interface, above which the resulting compound throughput is less than that of a single 60 GHz interface.
[1]
M. Baddeley, R. Nejabati, G. Oikonomou, M. Sooriyabandara, D. Simeonidou, "Evolving SDN for Low-Power IoT Networks", in Proc. NetSoft, 2018
@INPROCEEDINGS{Baddeley-2018-netsoft, title = {Evolving SDN for Low-Power IoT Networks}, author = {Michael Baddeley and Reza Nejabati and George Oikonomou and Mahesh Sooriyabandara and Dimitra Simeonidou}, booktitle = {Proc. NetSoft}, year = {2018}, oa-url = {https://research-information.bristol.ac.uk/en/publications/evolving-sdn-for-lowpower-iot-networks(f9eb201c-8800-45af-bab5-6b86d440e952).html}, gsid = {13759044828155681085}, abstract = {Software Defined Networking (SDN) offers a flexible and scalable architecture that abstracts decision making away from individual devices and provides a programmable network platform. Low-power wireless Internet of Things (IoT) networks, where multi-tenant and multi-application architectures require scalable and configurable solutions, are ideally placed to capitalize on this research. However, implementing a centralized SDN architecture within the constraints of a low-power wireless network faces considerable challenges. Not only is controller traffic subject to jitter due to unreliable links and network contention, but the overhead generated by SDN can severely affect the performance of other traffic. This paper addresses the challenge of bringing high-overhead SDN architecture to IEEE 802.15.4 networks. We explore how the traditional view of SDN needs to evolve in order to overcome the constraints of low-power wireless networks, and discuss protocol and architectural optimizations necessary to reduce SDN control overhead - the main barrier to successful implementation. Additionally, we argue that interoperability with the existing protocol stack is necessary to provide a platform for controller discovery, and coexistence with legacy networks. We consequently introduce µSDN, a lightweight SDN framework for Contiki OS with both IPv6 and underlying routing protocol interoperability, as well as optimizing a number of elements within the SDN architecture to reduce control overhead to practical levels. We evaluate µSDN in terms of latency, energy, and packet delivery. Through this evaluation we show how the cost of SDN control overhead (both bootstrapping and management) can be reduced to a point where comparable performance and scalability is achieved against an IEEE 802.15.4-2012 RPL-based network. Additionally, we demonstrate µSDN through simulation: providing a use-case where the SDN configurability can be used to provide Quality of Service (QoS) for critical network flows experiencing interference, and we achieve considerable reductions in delay and jitter in comparison to a scenario without SDN.}, }
Software Defined Networking (SDN) offers a flexible and scalable architecture that abstracts decision making away from individual devices and provides a programmable network platform. Low-power wireless Internet of Things (IoT) networks, where multi-tenant and multi-application architectures require scalable and configurable solutions, are ideally placed to capitalize on this research. However, implementing a centralized SDN architecture within the constraints of a low-power wireless network faces considerable challenges. Not only is controller traffic subject to jitter due to unreliable links and network contention, but the overhead generated by SDN can severely affect the performance of other traffic. This paper addresses the challenge of bringing high-overhead SDN architecture to IEEE 802.15.4 networks. We explore how the traditional view of SDN needs to evolve in order to overcome the constraints of low-power wireless networks, and discuss protocol and architectural optimizations necessary to reduce SDN control overhead - the main barrier to successful implementation. Additionally, we argue that interoperability with the existing protocol stack is necessary to provide a platform for controller discovery, and coexistence with legacy networks. We consequently introduce µSDN, a lightweight SDN framework for Contiki OS with both IPv6 and underlying routing protocol interoperability, as well as optimizing a number of elements within the SDN architecture to reduce control overhead to practical levels. We evaluate µSDN in terms of latency, energy, and packet delivery. Through this evaluation we show how the cost of SDN control overhead (both bootstrapping and management) can be reduced to a point where comparable performance and scalability is achieved against an IEEE 802.15.4-2012 RPL-based network. Additionally, we demonstrate µSDN through simulation: providing a use-case where the SDN configurability can be used to provide Quality of Service (QoS) for critical network flows experiencing interference, and we achieve considerable reductions in delay and jitter in comparison to a scenario without SDN.
Powered by bibtexbrowser
Conditions for Downloading Publications from This Site.

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. These works may not be reposted without explicit permission from the copyright holder.

Filter / Sort
Reset