The SaS Seminars are a permanent series of open seminars of the Division of Software and Systems (SaS) at the Department of Computer and Information Science (IDA), Linköping University. The objective of the seminars is to present outstanding research and ideas/problems relevant for SaS present and future activities. In particular, seminars cover the SaS research areas software engineering, programming environments, system software, embedded SW/HW systems, computer systems engineering, realtime systems, parallel and distributed computing, and theoretical computer science. - Two kinds of seminars are planned:

• talks by invited speakers not affiliated with SaS,

• internal seminars presenting lab research to whole SaS.

The speakers are expected to give a broad perspective of the presented research, adressing the audience with a general computer science background but possibly with no specific knowledge in the domain of the presented research. The normal length of a presentation is 60 minutes, including discussion.

The SaS seminars are coordinated by Ahmed Rezine.

Recent / Upcoming SaS Seminars (2016)

Latency reduction for soft real-time traffic using SCTP multihoming

Johan Eklund, Dr., Karlstad University, Sweden

Thursday, December 8th, 2016, 13:15-14:15, room John von Neumann

Abstract:
More and more so-called soft real-time traffic is being sent over IP-based networks. The bursty, data-limited traffic pattern as well as the latency requirements from this traffic present challenges to the traditional communication techniques. To meet the requirements from soft real-time traffic the transport protocol, Stream Control Transmission Protocol (SCTP) was designed. Its support for connectivity to multiple networks, i.e., multihoming, provides a) improved robustness and opens up for b) concurrent multipath transfer (CMT) over multiple paths as well as for c) handover of media sessions between heterogeneous networks. This presentation addresses latency reduction for soft real-time traffic using SCTP multihoming from the three above perspectives. The first focus is on latency for telephony signaling traffic in case of path switch, failover. The second focus is on latency for signaling traffic using CMT. In this scenario, the target is sender-side scheduling. The final scenario is multihomed SCTP to provide for handover of a media session between heterogeneous wireless networks in a mobile scenario.

Bio of speaker:
Johan Eklund received a B.Sc. in Computer Science from Karlstad University in 2001, and a M.S in Computer Science from the same university in 2004. He joined the Department of Computer Science at Karlstad University, in 2001. He is currently working as a part time lecturer and has just defended his PhD thesis on performance issues related to computer communication. In particular, he focuses on latency aspects for real time applicatiosn communicating over IP. Johan is also responsible for the collaboration between academia and the regional IT-industry, SNITS.

Scalable and Efficient On-Demand Video Streaming: Retrospective and Recent Work

Derek Eager, Professor, University of Saskatchewan, Canada

Tuesday, Nov. 22, 2016, 13:15-14:15, room Alan Turing

Abstract:
Streaming video is responsible for more than half of all Internet traffic. This talk will begin with a retrospective on the speaker's past work, with a variety of collaborators and over many years, on techniques for achieving scalable and efficient delivery of streaming video through aggregation of requests. Two recent projects will then be described that concern improving scalability and efficiency by other means. The first project is joint work with Niklas Carlsson (Linkoping U.) and concerns edge-network caching in the context of applications with high rates of addition of new content, most of which will be accessed only a small number of times from any particular edge network. The second project concerns improving server efficiency. Most streaming video is now delivered by web servers over HTTP rather than using dedicated video servers, and these web servers are not necessarily tuned for efficient video delivery. This portion of the talk will focus in particular on ! joint work with Jim Summers and Tim Brecht (U. of Waterloo) and Alex Gutarin (Netflix) on characterizing the workload of a Netflix server and implications for improving server efficiency.

Bio of speaker:
Derek Eager is a Professor in the Department of Computer Science at the University of Saskatchewan, Canada. He received the Ph.D. degree in Computer Science from the University of Toronto, Canada. His research interests are in the areas of performance evaluation, content distribution, distributed systems, and networks. Past professional activities include service as Chair of SIGMETRICS, the ACM Special Interest Group on performance evaluation, and service as program chair and as a general co-chair for the annual SIGMETRICS conference. In 2010 he was a co-recipient of one of the three inaugural ACM SIGMETRICS Test of Time Awards.

Modeling Memory Performance and that too symbolically: Failures, successes and everything in between

Sudipta Chattopadhyay, Dr., Saarlands University, Germany

Thursday, November 17th, 2016, 10:15-11:15, room John von Neumann

Abstract:
In this talk, I will present our past and ongoing works on symbolically modeling memory performance. In contrast to most research-oriented presentations, which only describe the end result, I will describe the process of our research. In particular, I will describe how we came up with ideas that failed and how that helped us to came up with the idea that works and finally, how we refined the idea over the duration of the research project. During this process, I will outline three systems MESS, CATAPULT and CHALICE, all based on the central idea of symbolic modeling and are targeted to be applied for performance debugging and information leak detection.

Bio of speaker:
Sudipta is currently affiliated with the Center for IT-Security, Privacy and Accountability (CISPA) and the Software Engineering Chair leaded by Prof. Andreas Zeller. Before coming to Germany, he was a post-doctoral researcher at IDA, where he primarily worked in ESLAB. He has obtained his Ph.D. in Computer Science from National University of Singapore (NUS), Singapore in 2013. Prior to his PhD study, he was working as a Research and Development Engineer in Synopsys for 1.5 years. His research interests broadly cover the area of Program Analysis, Embedded Systems and Compilers.

Programming and composing safely large-scale distributed applications with active objects

Ludovic Henrio, Dr., CNRS/I3S/Univ. of Nice Sophia Antipolis, France

Monday, October 3rd, 2016, 10:15-11:15, room John von Neumann

Abstract:
Active objects is a programming paradigm strongly inspired from actors. In this talk, I will first present the active object programming model, and the different languages that implement it. I will also focus more particularly on the active object language that we develop in our team: the ASP model, and its reference implementation: ProActive. Multi-active objects is the last extension of ASP and ProActive; it supports local concurrency and global distribution at the same time. I will also show how this model is efficient and particularly expressive. Finally, I will present different efforts in applying formal methods to this programming model and to software components in order to ensure the correctness of programming languages and of distributed applications.

Bio of speaker:
Ludovic Henrio is a researcher at CNRS I3S, he is scientific leader of the SCALE team. He graduated from Ecole Polytechnique in 1999, obtained a PhD from Univ. of Nice Sophia-Antipolis in 2003, and his habilitation in 2012. His research focuses on the design of programming languages and the development of formal aspects of distributed objects with a strong link to application domains. His research interests include programming languages, distributed objects and components, verification of programs, distributed systems. He has co-authored more than 50 papers in international journals and conferences and has participated significantly to European and national projects including NoE CoreGrid, IP BioNets, and FSN OpenCloudWare.

An Efficient Cloud Market Mechanism for Computing Jobs with Soft Deadlines

Zongpeng Li, Professor, University of Calgary, Canada

Friday, April 8, 2016, 13:15-14:15, room John von Neumann

Abstract:
We study the cloud market for computing jobs with completion deadlines, and designs efficient online auctions for cloud resource provisioning. A cloud user bids for future cloud resources to execute its job. Each bid includes (a) a utility, reflecting the amount that the user is willing to pay for executing its job, and (b) a soft deadline, specifying the preferred finish time of the job, as well as a penalty function that characterizes the cost of violating the deadline. We target cloud job auctions that executes in an online fashion, runs in polynomial time, provides truthfulness guarantee, and achieves optimal social welfare for the cloud ecosystem. Towards these goals, we leverage the following classic and new auction design techniques. First, we adapt the posted pricing auction framework for eliciting truthful online bids. Second, we address the challenge posed by soft deadline constraints through a new technique of compact exponential-size LPs coupled with dual separat! ion oracles. Third, we develop efficient social welfare approximation algorithms using the classic primal-dual framework based on both LP duals and Fenchel duals. Empirical studies driven by real-world traces verify the efficacy of our online auction design.

Bio of speaker:
Zongpeng Li received his B.E. degree in Computer Science and Technology from Tsinghua University (Beijing) in 1999, his M.S. degree in Computer Science from University of Toronto in 2001, and his Ph.D. degree in Electrical and Computer Engineering from University of Toronto in 2005. He has been with the University of Calgary since 2005, where he is now Professor of Computer Science. In 2011-2012, Zongpeng was a visitor at the Institute of Network Coding, Chinese University of Hong Kong. His research interests are in computer networks, network coding, cloud computing, and energy networks. Zongpeng was named an Edward S. Rogers Sr. Scholar in 2004, won the Alberta Ingenuity New Faculty Award in 2007, was nominated for the Alfred P. Sloan Research Fellow in 2007, and received Best Paper Awards at PAM 2008 and at HotPOST 2012. In 2014, Zongpeng received the Department Excellence Award from the Department of Computer Science, University of Calgary. Zongpeng is also a recipient of! the "Outstanding Young Computer Science Researcher" prize from the Canadian Association of Computer Science (2015).

A review of cyber security risk assessment methods for SCADA systems

Dr Yulia Cherdantseva, research associate, Cardiff University, UK

April 7th, kl 13.15-14.15 room John von Neumann

Abstract:
Recently, in the framework of SCADA Cyber Security Lifecycle (SCADA-CSL) programme funded by the Airbus Group Endeavr Wales we have conducted a review of cyber security risk assessment methods for Supervisory Control and Data Acquisition (SCADA) systems . The review is presented here. This paper is currently the most downloaded article at Computers & Security.

In this talk I will cover the results of our review as well as the review methodology and research challenges identified. For the review, we selected and in-detail examined twenty-four risk assessment methods developed for or applied in the context of a SCADA system. We analysed the methods in terms of aim; application domain; the stages of risk management addressed; key risk management concepts covered; impact measurement; sources of probabilistic data; evaluation and tool support. Based on the analysis, we suggested an intuitive scheme for the categorisation of cyber security risk assessment methods for SCADA systems. Most importantly, we outlined five research challenges facing risk assessment in SCADA systems and pointed out the approaches that might be taken.

Device Analyzer: 3500 years of handset usage data

Senior lecturer Andrew Rice, Cambridge university, UK

April 1st, kl 10.15-11.15 room John von Neumann

Abstract:
Our Device Analyzer project has collected Android usage data from more than 20,000 people around the world. We have a huge range of contributions ranging from days to years. I'll describe some of the studies that have been done with the data covering tracking security vulnerabilities, movement patterns, WiFi channel allocation, SMS message lengths, and session durations. We are actively sharing the data with other researchers and I'll explain how this process works and what we've learned from it.

The speaker:
Andrew Rice is a university Senior Lecturer in the University of Cambridge Computer Laboratory working in the Digital Technology Group. He is also the Hassabis Fellow in Computer Science and Director of Studies in Computer Science at Queens' College.

Previous SaS Seminars

• 2015
• 2014
• 2013
• 2012
• 2011
• 2010
• 2009
• 2008
• 2007
• 2006
• 2005
• 2004
• 2003
• 2002
• 2001

Page responsible: Christoph Kessler
Last updated: 2017-06-29