EURASIP Journal on Wireless Communications and Networking, 2014
Data acquisition in large wireless sensor networks consisting of only a single sink can typically... more Data acquisition in large wireless sensor networks consisting of only a single sink can typically lead to scalability and energy efficiency issues. A solution to this problem is the deployment of multiple sinks in the network. This approach is however not supported by the popular sensor network routing protocol, IPv6 routing protocol for low-power and lossy networks (RPL). This paper describes a method to support the usage of multiple sinks for RPL in accordance to the limited guidelines of RPL: IPv6 Routing Protocol for Low-Power and Lossy Networks (RFC 6550). Hereby this paper shows that the concept of a virtual root can work and can be implemented with a minimal complexity. The correct behaviour of this extension was verified, by performance tests, in both a simulation environment and a real-life environment (iMinds wiLab.t office testbed). The chosen approach has the advantage that for an existing deployment of a RPL network, only the sink nodes need to be adapted. The results confirm that the use of multiple sinks in RPL can deliver the desired advantages. For an increase in the number of sinks from 1 to 4, a decrease of about 45% in the maximal and more than 30% in the average energy consumption was obtained in simulations for the used topology. For the real-life tests, the average energy consumption decreased with more than 30% and with more than 50% for the maximal energy consumption when the number of sinks was increased from 1 to 2 on the iMinds wiLab.t office testbed. By using a positioning algorithm to determine the optimal position, for the sinks, possibly even better performances can be obtained.
2009 9th International Conference on Intelligent Transport Systems Telecommunications, (ITST), 2009
This paper presents a model for assessing the impact of introducing nationwide road charging syst... more This paper presents a model for assessing the impact of introducing nationwide road charging systems on supporting mobile data networks. It defines a model based on real traffic measurements, and establishes appropriate parameter values for capturing specific application characteristics such as the importance of data compression, truck-only versus all traffic charging, and dimensioning margins for handling peak days. Finally, this paper applies the developed model and defined parameter values to a Belgian case study.
Smart embedded objects will become an important part of what is called the Internet of Things. Ho... more Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there were many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. Long time, most efforts were focusing on the networking layer. More recently, the IETF CoRE working group started working on an embedded counterpart of HTTP, allowing the integration of constrained devices into existing service networks. In this paper, we will briefly review the history of integrating constrained devices into the Internet, with a prime focus on the IETF standardization work in the ROLL and CoRE working groups. This is further complemented with some research results that illustrate how these novel technologies can be extended or used to tackle other problems.
Several networking approaches exist in the domain of Vehicular Ad Hoc Networks (VANET). IPv6 netw... more Several networking approaches exist in the domain of Vehicular Ad Hoc Networks (VANET). IPv6 networking, non-IP geographical networking, or a combination of both of them is commonly used as the foundation of the developed solutions. In this paper, an addressing scheme is proposed that incorporates all required geographical data in a standard IPv6 header.
... Due to saturation of the wireless medium ▪Possible solutions ▪More efficient VANET routing pr... more ... Due to saturation of the wireless medium ▪Possible solutions ▪More efficient VANET routing protocols ▪More efficient VANET broadcast protocols ▪Optimization of QoS mechanisms on MAC layer ▪Cross-layer optimizations Scalability problem CALM User Services / Applications ...
In the past research has been done on cooperative systems resulting in, among others, the CALM ar... more In the past research has been done on cooperative systems resulting in, among others, the CALM architecture which is used in NextGenITS. The project focuses on the scalability issues of routing protocols and energy optimizations for cooperative vehicular ad hoc network (VANET) ...
Smart embedded objects will become an important part of what is called the Internet of Things. H... more Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there have been many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. In this paper, we will briefly review the history of integrating constrained devices into the Internet, followed by an extensive overview of IETF standardization work in the 6LoWPAN, ROLL and CoRE working groups. This is complemented with a broad overview of related research results that illustrate how this work can be extended or used to tackle other problems and with a discussion on open issues and challenges. As such the aim of this paper is twofold: apart from giving readers solid insights in IETF standardization work on the Internet of Things, it also aims to encourage readers to further explore the world of Internet-connected objects, pointing to future research opportunities.
Smart embedded objects will become an important part of what is called the Internet of Things. Ho... more Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there have been many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. In this paper, we will briefly review the history of integrating constrained devices into the Internet, followed by an extensive overview of IETF standardization work in the 6LoWPAN, ROLL and CoRE working groups. This is complemented with a broad overview of related research results that illustrate how this work can be extended or used to tackle other problems and with a discussion on open issues and challenges. As such the aim of this paper is twofold: apart from giving readers solid insights in IETF standardization work on the Internet of Things, it also aims to encourage readers to further explore the world of Internet-connected objects, pointing to future research opportunities. OPEN ACCESS J. Sens. Actuator Netw. 2013, 2 236 239
EURASIP Journal on Wireless Communications and Networking, 2014
Data acquisition in large wireless sensor networks consisting of only a single sink can typically... more Data acquisition in large wireless sensor networks consisting of only a single sink can typically lead to scalability and energy efficiency issues. A solution to this problem is the deployment of multiple sinks in the network. This approach is however not supported by the popular sensor network routing protocol, IPv6 routing protocol for low-power and lossy networks (RPL). This paper describes a method to support the usage of multiple sinks for RPL in accordance to the limited guidelines of RPL: IPv6 Routing Protocol for Low-Power and Lossy Networks (RFC 6550). Hereby this paper shows that the concept of a virtual root can work and can be implemented with a minimal complexity. The correct behaviour of this extension was verified, by performance tests, in both a simulation environment and a real-life environment (iMinds wiLab.t office testbed). The chosen approach has the advantage that for an existing deployment of a RPL network, only the sink nodes need to be adapted. The results confirm that the use of multiple sinks in RPL can deliver the desired advantages. For an increase in the number of sinks from 1 to 4, a decrease of about 45% in the maximal and more than 30% in the average energy consumption was obtained in simulations for the used topology. For the real-life tests, the average energy consumption decreased with more than 30% and with more than 50% for the maximal energy consumption when the number of sinks was increased from 1 to 2 on the iMinds wiLab.t office testbed. By using a positioning algorithm to determine the optimal position, for the sinks, possibly even better performances can be obtained.
2009 9th International Conference on Intelligent Transport Systems Telecommunications, (ITST), 2009
This paper presents a model for assessing the impact of introducing nationwide road charging syst... more This paper presents a model for assessing the impact of introducing nationwide road charging systems on supporting mobile data networks. It defines a model based on real traffic measurements, and establishes appropriate parameter values for capturing specific application characteristics such as the importance of data compression, truck-only versus all traffic charging, and dimensioning margins for handling peak days. Finally, this paper applies the developed model and defined parameter values to a Belgian case study.
Smart embedded objects will become an important part of what is called the Internet of Things. Ho... more Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there were many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. Long time, most efforts were focusing on the networking layer. More recently, the IETF CoRE working group started working on an embedded counterpart of HTTP, allowing the integration of constrained devices into existing service networks. In this paper, we will briefly review the history of integrating constrained devices into the Internet, with a prime focus on the IETF standardization work in the ROLL and CoRE working groups. This is further complemented with some research results that illustrate how these novel technologies can be extended or used to tackle other problems.
Several networking approaches exist in the domain of Vehicular Ad Hoc Networks (VANET). IPv6 netw... more Several networking approaches exist in the domain of Vehicular Ad Hoc Networks (VANET). IPv6 networking, non-IP geographical networking, or a combination of both of them is commonly used as the foundation of the developed solutions. In this paper, an addressing scheme is proposed that incorporates all required geographical data in a standard IPv6 header.
... Due to saturation of the wireless medium ▪Possible solutions ▪More efficient VANET routing pr... more ... Due to saturation of the wireless medium ▪Possible solutions ▪More efficient VANET routing protocols ▪More efficient VANET broadcast protocols ▪Optimization of QoS mechanisms on MAC layer ▪Cross-layer optimizations Scalability problem CALM User Services / Applications ...
In the past research has been done on cooperative systems resulting in, among others, the CALM ar... more In the past research has been done on cooperative systems resulting in, among others, the CALM architecture which is used in NextGenITS. The project focuses on the scalability issues of routing protocols and energy optimizations for cooperative vehicular ad hoc network (VANET) ...
Smart embedded objects will become an important part of what is called the Internet of Things. H... more Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there have been many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. In this paper, we will briefly review the history of integrating constrained devices into the Internet, followed by an extensive overview of IETF standardization work in the 6LoWPAN, ROLL and CoRE working groups. This is complemented with a broad overview of related research results that illustrate how this work can be extended or used to tackle other problems and with a discussion on open issues and challenges. As such the aim of this paper is twofold: apart from giving readers solid insights in IETF standardization work on the Internet of Things, it also aims to encourage readers to further explore the world of Internet-connected objects, pointing to future research opportunities.
Smart embedded objects will become an important part of what is called the Internet of Things. Ho... more Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there have been many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. In this paper, we will briefly review the history of integrating constrained devices into the Internet, followed by an extensive overview of IETF standardization work in the 6LoWPAN, ROLL and CoRE working groups. This is complemented with a broad overview of related research results that illustrate how this work can be extended or used to tackle other problems and with a discussion on open issues and challenges. As such the aim of this paper is twofold: apart from giving readers solid insights in IETF standardization work on the Internet of Things, it also aims to encourage readers to further explore the world of Internet-connected objects, pointing to future research opportunities. OPEN ACCESS J. Sens. Actuator Netw. 2013, 2 236 239
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