MIPv6 Experimental Evaluation using Overlay Networks

The commercial deployment of Mobile IPv6 has been hastened by the concepts of Integrated Wireless Networks and Overlay Networks, which are present in the notion of the forthcoming generation of wireless communications. Individual wireless access networks show limitations that can be overcome through the integration of different technologies into a single unified platform (i.e., 4G systems). This paper summarises practical experiments performed to evaluate the impact of inter-networking (i.e. vertical handovers) on the Network and Transport layers. Based on our observations, we propose and evaluate a number of inter-technology handover optimisation techniques, e.g., Router Advertisements frequency values, Binding Update simulcasting, Router Advertisement caching, and Soft Handovers. The paper concludes with the description of a policy-based mobility support middleware (PROTON) that hides 4G networking complexities from mobile users, provides informed handover-related decisions, and enables the application of different vertical handover methods and optimisations according to context.Publicad

An investigation into the use of 3G mobile communications to provide telehealth services in rural KwaZulu-Natal

This article has been made available through the Brunel Open Access Publishing Fund.Abstract Background: We investigated the use of third-generation (3G) mobile communications to provide telehealth services in remote health clinics in rural KwaZulu-Natal, South Africa. Materials and Methods: We specified a minimal set of services as our use case that would be representative of typical activity and to provide a baseline for analysis of network performance. Services included database access to manage chronic disease, local support and management of patients (to reduce unnecessary travel to the hospital), emergency care (up to 8 h for an ambulance to arrive), e-mail, access to up-to-date information (Web), and teleclinics. We made site measurements at a representative set of health clinics to determine the type of coverage (general packet radio service [GPRS]/3G), its capabilities to support videoconferencing (H323 and Skype™ [Microsoft, Redmond, WA]) and audio (Skype), and throughput for transmission control protocol (TCP) to gain a measure of application performance. Results: We found that none of the remote health clinics had 3G service. The GPRS service provided typical upload speed of 44 kilobits per second (Kbps) and download speed of 64 Kbps. This was not sufficient to support any form of videoconferencing. We also observed that GPRS had significant round trip time (RTT), in some cases in excess of 750 ms, and this led to slow start-up for TCP applications. Conclusions: We found audio was always so broken as to be unusable and further observed that many applications such as Web access would fail under conditions of very high RTT. We found some health clinics were so remote that they had no mobile service. 3G, where available, had measured upload speed of 331 Kbps and download speed of 446 Kbps and supported videoconferencing and audio at all sites, but we frequently experienced 3G changing to GPRS. We conclude that mobile communications currently provide insufficient coverage and capability to provide reliable clinical services and would advocate dedicated wireless services where reliable communication is essential and use of store and forward for mobile applications.The Royal Society, United Kingdom

Seamless mobility with personal servers

We describe the concept and the taxonomy of personal servers, and their implications in seamless mobility. Personal servers could offer electronic services independently of network availability or quality, provide a greater flexibility in the choice of user access device, and support the key concept of continuous user experience. We describe the organization of mobile and remote personal servers, define three relevant communication modes, and discuss means for users to exploit seamless services on the personal server

Web browsing optimization over 2.5G and 3G: end-to-end mechanisms vs. usage of performance enhancing proxies

Published version on Wiley's platform: https://onlinelibrary.wiley.com/doi/abs/10.1002/wcm.4562.5 Generation (2.5G) and Third Generation (3G) cellular wireless networks allow mobile Internet access withbearers specifically designed for data communications. However, Internet protocols under-utilize wireless widearea network (WWAN) link resources, mainly due to large round trip times (RTTs) and request–reply protocolpatterns. Web browsing is a popular service that suffers significant performance degradation over 2.5G and 3G. Inthis paper, we review and compare the two main approaches for improving web browsing performance over wirelesslinks: (i) using adequate end-to-end parameters and mechanisms and (ii) interposing a performance enhancingproxy (PEP) between the wireless and wired parts. We conclude that PEPs are currently the only feasible way forsignificantly optimizing web browsing behavior over 2.5G and 3G. In addition, we evaluate the two main currentcommercial PEPs over live general packet radio service (GPRS) and universal mobile telecommunications system(UMTS) networks. The results show that PEPs can lead to near-ideal web browsing performance in certain scenarios.Postprint (published version

Characterisation of real GPRS traffic with analytical tools

With GPRS and UMTS networks lunched, wireless multimedia services are commercially becoming the most attractive applications next to voice. Because of the nature of bursty, packet-switched schemes and multiple data rates, the traditional Erlang approach and Poisson models for characterising voice-centric services traffic are not suitable for studying wireless multimedia services traffic. Therefore, research on the characterisation of wireless multimedia services traffic is very challenging. The typical reference for the study of wireless multimedia services traffic is wired Internet services traffic. However, because of the differences in network protocol, bandwidth, and QoS requirements between wired and wireless services, their traffic characterisations may not be similar. Wired network Internet traffic shows self-similarity, long-range dependence and its file sizes exhibit heavy-tailedness. This paper reports the use of existing tools to analyse real GPRS traffic data to establish whether wireless multimedia services traffic have similar properties as wired Internet services traffic

Synchrophasor Communication over Internet: Performance Analysis of different Methods based on Real Experiences

This paper presents a theoretical description and a practical experience in different synchrophasor communication methods applied in real implementations of PMUs connected over both a wired and a mobile internet link. The analyzed methods are proposed in the IEEE Standard C37.118.2-2011 and are the most used in the literature and real applications including commercial PMUs. A complete description is presented and the main characteristics, advantages and disadvantages, including network efficiency algorithms that can affect PMU link are discussed. As PMUs are being applied on existing power systems in developing countries, where dedicated Ethernet or fiber-optic links are not always available, wired internet connections and GSM/GPRS usually become the only possible solutions. Performance of PMUs over Internet, in terms of data frames quality and latency, is analyzed by means of tests designed for this purpose, and statistical analysis of results from real experiences is presented and compared with real applications requirements.Paper 19PESGM0341.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctrico

Integration of heterogeneous devices and communication models via the cloud in the constrained internet of things

As the Internet of Things continues to expand in the coming years, the need for services that span multiple IoT application domains will continue to increase in order to realize the efficiency gains promised by the IoT. Today, however, service developers looking to add value on top of existing IoT systems are faced with very heterogeneous devices and systems. These systems implement a wide variety of network connectivity options, protocols (proprietary or standards-based), and communication methods all of which are unknown to a service developer that is new to the IoT. Even within one IoT standard, a device typically has multiple options for communicating with others. In order to alleviate service developers from these concerns, this paper presents a cloud-based platform for integrating heterogeneous constrained IoT devices and communication models into services. Our evaluation shows that the impact of our approach on the operation of constrained devices is minimal while providing a tangible benefit in service integration of low-resource IoT devices. A proof of concept demonstrates the latter by means of a control and management dashboard for constrained devices that was implemented on top of the presented platform. The results of our work enable service developers to more easily implement and deploy services that span a wide variety of IoT application domains

Synchrophasor Communication over Internet: Performance Analysis of different Methods based on Real Experiences

This paper presents a theoretical description and a practical experience in different synchrophasor communication methods applied in real implementations of PMUs connected over both a wired and a mobile internet link. The analyzed methods are proposed in the IEEE Standard C37.118.2-2011 and are the most used in the literature and real applications including commercial PMUs. A complete description is presented and the main characteristics, advantages and disadvantages, including network efficiency algorithms that can affect PMU link are discussed. As PMUs are being applied on existing power systems in developing countries, where dedicated Ethernet or fiber-optic links are not always available, wired internet connections and GSM/GPRS usually become the only possible solutions. Performance of PMUs over Internet, in terms of data frames quality and latency, is analyzed by means of tests designed for this purpose, and statistical analysis of results from real experiences is presented and compared with real applications requirements.Paper 19PESGM0341.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctrico

Synchrophasor Communication over Internet: Performance Analysis of different Methods based on Real Experiences

This paper presents a theoretical description and a practical experience in different synchrophasor communication methods applied in real implementations of PMUs connected over both a wired and a mobile internet link. The analyzed methods are proposed in the IEEE Standard C37.118.2-2011 and are the most used in the literature and real applications including commercial PMUs. A complete description is presented and the main characteristics, advantages and disadvantages, including network efficiency algorithms that can affect PMU link are discussed. As PMUs are being applied on existing power systems in developing countries, where dedicated Ethernet or fiber-optic links are not always available, wired internet connections and GSM/GPRS usually become the only possible solutions. Performance of PMUs over Internet, in terms of data frames quality and latency, is analyzed by means of tests designed for this purpose, and statistical analysis of results from real experiences is presented and compared with real applications requirements.Paper 19PESGM0341.Instituto de Investigaciones Tecnológicas para Redes y Equipos Eléctrico