Swedish Institute of Computer Science Publications Database
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Demo Abstract: SicsthSense - Dispersing the Cloud
No full text—This demo presents SicsthSense, our open cloud
platform for the Internet of Things. SicsthSense enables low
power devices such as sensor nodes and smartphones to easily
store their generated data streams in the cloud. This allows the
data streams, and their history, to be made permanently available
to users for visualisation, processing and sharing. Moving sensor
data computation and monitoring into the cloud is a promising
avenue to enable centralisation of control and redistribution of
collected data.
We showcase SicsthSense running with real sensor nodes
collecting environmental data and posting it to our datastore.
This live data is then visualised and made available for sharing
between users of the platform. Our Android App will also be
distributed to enable participants to stream their phone sensors
into the system, demonstrating how simple it can be to start
machine-to-machine interactions with SicsthSense
Authorization for Industrial Control Systems
No full textEvery day more and more devices are getting connected to the Internet, a phenomenon commonly referred to as the Internet of Things. Since security and privacy are more important than ever before this presents an interesting problem. Suddenly devices with not even near as much computing power as a desktop computer are tasked with performing heavy security computations designed to be
used in powerful systems with little resource and power limitations. This thesis presents a solution for performing authorization for a resource limited system using a trusted third party, thus transferring the usually quite heavy authorization computations from a resource constrained device to another device where no such restrictions exists. When a client wishes to request a resource on the constrained device it must first retrieve authorization information from the third party and include this in the request. The authorization information is then validated by
confirming that it originates from the trusted third party using a shared secret. In this thesis the constrained system is represented by an ABB control system of model 800xA and by transferring the authorization cost to another system the increased amount of resource usage on this device is kept to a minimum. It is also shown that this increase is negligible compared to the increase in resource usage when authentication and message protection in the form of TLS was implemented
Affordable Separation on Embedded Platforms: Soft Reboot Enabled Virtualization on a Dual Mode System
No full textWhile security has become important in embedded systems, commodity operating systems often fail in effectively separating processes, mainly due to a too large trusted computing base. System virtualization can establish isolation already with a small code base, but many existing embedded CPU architectures have very limited virtualization hardware support, so that the performance impact is often non-negligible. Targeting both security and performance, we investigate an approach in which a few minor hardware additions together with virtualization offer protected execution in embedded systems while still allowing non-virtualized execution when secure services are not needed. Benchmarks of a prototype implementation on an emulated ARM Cortex A8 platform confirm that switching between those two execution forms can be done efficiently
An Integrated Constraint Programming Approach to Scheduling Sports Leagues with Divisional and Round-Robin Tournaments
No full textPrevious approaches for scheduling a league with round-robin and divisional tournaments involved decomposing the problem into easier subproblems. This approach, used to schedule the top Swedish handball league Elitserien, reduces the problem complexity but can result in suboptimal schedules. This paper presents an integrated constraint programming model that allows to perform the scheduling in a single step. Particular attention is given to identifying implied and symmetry-breaking constraints that reduce the computational complexity significantly. The experimental evaluation of the integrated approach takes considerably less computational effort than the previous approach
Trusted Geolocation-Aware Data Placement in Infrastructure Clouds
No full textData geolocation in the cloud is becoming an increasingly pressing problem, aggravated by incompatible legislation in different jurisdictions and compliance requirements of
data owners. In this work we present a mechanism allowing cloud users to control the geographical location of their data, stored or processed in plaintext on the premises of Infrastructure-as-a-Service cloud providers. We use trusted computing principles and remote attestation to establish platform state. We enable cloud users to confine plaintext data exclusively to the jurisdictions they specify, by sealing decryption keys used to obtain plaintext data to the combination of cloud host geolocation and platform state. We provide a detailed description of the implementation as well as performance measurements on an open source cloud infrastructure platform using commodity hardware
BEAMJIT: a just-in-time compiling runtime for Erlang
No full textBEAMJIT is a tracing just-in-time compiling runtime for the Erlang
programming language. The core parts of BEAMJIT are synthesized from
the C source code of BEAM, the reference Erlang abstract machine. The
source code for BEAM's instructions is extracted automatically from
BEAM's emulator loop. A tracing version of the abstract machine, as
well as a code generator are synthesized. BEAMJIT uses the LLVM
toolkit for optimization and native code emission.
The automatic synthesis process greatly reduces the amount of manual
work required to maintain a just-in-time compiler as it automatically
tracks the BEAM system.
The performance is evaluated with HiPE's, the Erlang ahead-of-time
native compiler, benchmark suite. For most benchmarks BEAMJIT delivers
a performance improvement compared to BEAM, although in some cases,
with known causes, it fails to deliver a performance boost. BEAMJIT
does not yet match the performance of HiPE mainly because it does not
yet implement Erlang specific optimizations such as boxing/unboxing
elimination and a deep understanding of BIFs. Despite this BEAMJIT,
for some benchmarks, reduces the runtime with up to 40\%
A social practice perspective on the smart grid
No full textAbstract—This is a summary of the workshop that was held as part of the ICT4S conference with a focus on the topic of social practices and smart grids. Here we present an overview of the five invited paper contributions to the workshop, as well as a summary of the plenary discussion, and our final conclusions
