Swedish Institute of Computer Science Publications Database
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Snot, Sweat, Pain, Mud, and Snow - Performance and Experience in the Use of Sports Watches
We have conducted interviews with ten elite and recreational athletes to understand their experiences and engagement with endurance sport and personal and wearable sports technology. In the interviews, athletes emphasized the experiential aspects of doing sports and the notion of feeling was repeatedly used to talk about their activities. The technology played both an instrumental role in measuring performance and feeding bio-data back to them, and an experiential role in supporting and confirming the sport experience. To guide further interaction design research in the sports domain, we suggest two interrelated ways of looking at sports performances and experiences, firstly through the notion of a measured sense of performance, and secondly as a lived-sense of performance
Systems-of-systems for border-crossing innovation in the digitized society - A strategic research and innovation agenda for Sweden
This report constitutes a strategic research and innovation agenda for the area systems-of-systems. The agenda has been developed during the first half of 2015 in a project led by SICS Swedish ICT AB, in collaboration with INCOSE Sweden and a large number of representatives from industry and academia, with financial support from Vinnova. The overall conclusion of the agenda is: Sweden needs a world-leading capability to rapidly develop trustworthy systems-of-systems.
A system-of-systems (SoS) can informally be defined as a group of independent collaborating systems. The elements of an SoS, called constituent systems, retain an operational and managerial independence, but when combined in a certain way, they provide together a new capability that is emergent from their cooperation. There are many applications of SoS, often as a consequence of the digitization of society which opens new possibilities for system integration. Examples can be found within command and control systems for defense and civilian crisis management; construction and mining; manufacturing and the reindustrialization; transportation; and health care. System integration is traditionally a Swedish area of strength, and by improving SoS knowledge, competitive advantages can be reached. SoS is also an important enabler for innovation, through the ability to combine existing technical products, processes, and organizations in new ways. Having the ability for rapid SoS development is very important for businesses to bring new innovations to market. However, to advance the practice of SoS engineering, a number of challenges need to be addressed, including improving the theoretical foundations; the socio-technical aspects; architecture; modeling and simulation; interoperability; trust; business and legal aspects; development processes and methods; and standardization.
As part of the agenda project, a survey has been done of international and Swedish research in the area. Internationally, the SoS field is dominated by US researchers, with a very strong focus on military and space applications. A large number of people are involved, but few persons focus on the area. In comparison, Sweden has entered the research area much later, and only now is attention growing. As is the case internationally, few researchers focus on SoS, and many of them do not even call their research SoS. Activities are scattered over many organizations throughout the country. Many of the researchers in SoS in Sweden come from a background in Software Engineering or Control Engineering, and this is in contrast with the international research, which has its basis in Systems Engineering. In Sweden, research topics such as business aspects (in particular innovation), control systems, governance, and Internet of Things are more pronounced than internationally. However, there is little research in Sweden on the underlying, fundamental principles of SoS engineering. This is likely to be in part a consequence of the funding strategies currently implemented. The analysis shows a broad but scattered Swedish research community lacking critical mass. There is a high competence in software and control engineering, and in empirical research methods, but the lack of systems engineering competence is alarming, since it is fundamental for desired advances, such as in the reindustrialization (Industry 4.0).
To achieve the desired capability in SoS development requires knowledge, competence, and capacity, which are provided through substantially increased research and education actions. It is suggested that research in the area is organized as a national SoS center-of-centers that coordinates activities at different academic member organizations. This requires increased research funding. There is also an urgent need for education in systems engineering, systems thinking, and SoS. It is proposed that the center-of-centers also takes responsibility for this, by developing joint courses in those disciplines, including on-line courses for practitioners, and PhD schools for industrial and academic doctoral students. To complement this, societal actions are needed to remove obstacles for building SoS, and enforcing standards. Finally, it is necessary to create meeting places, including triple helix flagship projects, that can fuel the interactions between individuals and organizations interested in SoS
Autonomous load balancing of heterogeneous networks
This paper presents a method for load balancing heterogeneous networks by dynamically assigning values to the LTE cell range expansion (CRE) parameter. The method records hand-over events online and adapts flexibly to changes in terminal traffic and mobility by maintaining statistical estimators that are used to support autonomous assignment decisions. The proposed approach has low overhead and is highly scalable due to a modularised and completely distributed design that exploits self- organisation based on local inter-cell interactions. An advanced simulator that incorporates terminal traffic patterns and mobility models with a radio access network simulator has been developed to validate and evaluate the method
Understanding usage and activity in cellular networks by investigating HTTP requests
The number of mobile devices is estimated to now exceed the world’s population, using more and more cloud services, and hence generating more and more traffic. Smartphones generate 95% of the total global handset traffic, and while approximately half of this traffic is sent to cellular networks, other handsets such as tablets are also using increasingly the cellular networks. This paper provides a closer look at the traffic generated on cellular networks by exploring billions of HTTP requests sent by millions of users to a nation-wide cellular network during 41 days. We confirm that - as in many other contexts - 20% of the users are responsible for more than 80% of the requests and provide a deeper analysis of the cellular network usage. Furthermore, we characterise the activity of users on their mobile device and which cloud services they use. For instance, almost 30% of the users use the cellular network frequently, mainly using search services and social networks, but 20% of their requests are sent to advertisement and tracking systems
Architectural Reasoning Support for Product-Lines of Self-adaptive Software Systems - A Case Study
Software architecture serves as a foundation for the design and development of software systems. Designing an architecture requires extensive analysis and reasoning. The study presented herein focuses on the architectural analysis and reasoning in support of engineering self-adaptive software systems with systematic reuse. Designing self-adaptive software systems with systematic reuse introduces variability along three dimensions; adding more complexity to the architectural analysis and reasoning process. To this end, the study presents an extended Architectural Reasoning Framework with dedicated reasoning support for self-adaptive systems and reuse. To evaluate the proposed framework, we conducted an initial feasibility case study, which concludes that the proposed framework assists the domain architects to increase reusability, reduce fault density, and eliminate differences in skills and experiences among architects, which were our research goals and are decisive factors for a system’s overall quality
Towards Secure Multi-tenant Virtualized Networks
Network virtualization enables multi-tenancy over physical network infrastructure, with a side-effect of increased network complexity. Software-defined networking (SDN) is a novel network architectural model – one where the control plane is separated from the data plane by a standardized API – which aims to reduce the network management overhead. However, as the SDN model itself is evolving, its application to multi-tenant virtualized networks raises multiple security challenges. In this paper, we present a security analysis of SDN- based multi-tenant virtualized networks: we outline the security assumptions applicable to such networks, define the relevant adversarial model, identify the main attack vectors for such network infrastructure deployments and finally synthesize a set of high-level security requirements for SDN-based multi-tenant virtualized networks. This paper sets the foundation for future design of secure SDN-based multi-tenant virtualized networks
Scalable Software Defined Monitoring for Service Provider DevOps
Technology trends such as Cloud, SDN, and NFV are transforming the telecommunications business, promising higher service flexibility and faster deployment times. They also allow for increased programmability of the infrastructure layers. We propose to split selected monitoring control functionality onto node-local control planes, thereby taking advantage of processing capabilities on programmable nodes. Our software defined monitoring approach provides telecom operators with a way to handle the trade off between high-granular monitoring information versus network and computation loads at central control and management layers. To illustrate the concept, a link rate monitoring function is implemented using node-local control plane components. Furthermore, we introduce a messaging bus for simple and flexible communication between monitoring function components as well as control and management systems. We investigate scalability gains with a numerical analysis, demonstrating that our approach would generate thousand fold less monitoring traffic while providing similar information granularity as a naive SNMP implementation or an Open Flow approach