34 research outputs found
Isomorphism between Linear Codes and Arithmetic Codes for Safe Data Processing in Embedded Software Systems
We present a transformation rule to convert linear codes into arithmetic codes. Linear codes are usually used for error detection and correction in broadcast and storage systems. In contrast, arithmetic codes are very suitable for protection of software processing in computer systems. This paper shows how to transform linear codes protecting the data stored in a computer system into arithmetic codes safeguarding the operations built on this data. Combination of the advantages of both coding mechanisms will increase the error detection capability in safety critical applications for embedded systems by detection and correction of arbitrary hardware faults
Causality and Functional Safety - How Causal Models Relate to the Automotive Standards ISO 26262, ISO/PAS 21448, and UL 4600
With autonomous driving, the system complexity
of vehicles will increase drastically. This requires new ap-
proaches to ensure system safety. Looking at standards like ISO
26262 or ISO/PAS 21448 and their suggested methodologies,
an increasing trend in the recent literature can be noticed to
incorporate uncertainty. Often this is done by using Bayesian
Networks as a framework to enable probabilistic reasoning.
These models can also be used to represent causal relationships.
Many publications claim to model cause-effect relations, yet
rarely give a formal introduction of the implications and
resulting possibilities such an approach may have. This paper
aims to link the domains of causal reasoning and automotive
system safety by investigating relations between causal models
and approaches like FMEA, FTA, or GSN. First, the famous
“Ladder of Causation” and its implications on causality are
reviewed. Next, we give an informal overview of common
hazard and reliability analysis techniques and associate them
with probabilistic models. Finally, we analyse a mixed-model
methodology called Hybrid Causal Logic, extend its idea, and
build the concept of a causal shell model of automotive system
safety
Security-Gateway for SCADA-Systems in Critical Infrastructures
The presented work is part of the research project Energy
Safe and Secure System Module (ES3M), which is funded by
the Project Management J ̈ulich (PtJ) and the German Federal
Ministry for Economic Affairs and Energy (BMWi) under
funding code 0350042ASupervisory Control and Data Acquisition
(SCADA) systems are used to control and monitor components
within the energy grid, playing a significant role in the
stability of the system. As a part of critical infrastructures,
components in these systems have to fulfill a variety of different
requirements regarding their dependability and must also
undergo strict audit procedures in order to comply with all
relevant standards. This results in a slow adoption of new
functionalities. Due to the emerged threat of cyberattacks
against critical infrastructures, extensive security measures are
needed within these systems to protect them from adversaries
and ensure a stable operation. In this work, a solution is
proposed to integrate extensive security measures into current
systems. By deploying additional security-gateways into the
communication path between two nodes, security features
can be integrated transparently for the existing components.
The developed security-gateway is compliant to all regulatory
requirements and features an internal architecture based on
the separation-of-concerns principle to increase its security
and longevity. The viability of the proposed solution has been
verified in different scenarios, consisting of realistic field tests,
security penetration tests and various performance evaluations
CausalOps -- Towards an Industrial Lifecycle for Causal Probabilistic Graphical Models
Causal probabilistic graph-based models have gained widespread utility,
enabling the modeling of cause-and-effect relationships across diverse domains.
With their rising adoption in new areas, such as automotive system safety and
machine learning, the need for an integrated lifecycle framework akin to DevOps
and MLOps has emerged. Currently, a process reference for organizations
interested in employing causal engineering is missing. To address this gap and
foster widespread industrial adoption, we propose CausalOps, a novel lifecycle
framework for causal model development and application. By defining key
entities, dependencies, and intermediate artifacts generated during causal
engineering, we establish a consistent vocabulary and workflow model. This work
contextualizes causal model usage across different stages and stakeholders,
outlining a holistic view of creating and maintaining them. CausalOps' aim is
to drive the adoption of causal methods in practical applications within
interested organizations and the causality community
An optimized Bitsliced Masked Adder for ARM Thumb-2 Controllers
The modular addition is used as a non-linear
operation in ARX ciphers because it achieves the requirement
of introducing non-linearity in a cryptographic primitive while
only taking one clock cycle to execute on most modern archi-
tectures. This makes ARX ciphers especially fast in software
implementations, but comes at the cost of making it harder to
protect against side-channel information leakages using Boolean
masking: the best known 2-shares masked adder for ARM
Thumb micro-controllers takes 83 instructions to add two 32-bit
numbers together. Our approach is to operate in bitsliced mode,
performing 32 additions in parallel on a 32-bit microcontroller.
We show that, even after taking into account the cost of bitslicing
before and after the encryption, it is possible to achieve a higher
throughput on the tested ciphers (CRAX and ChaCha20) when
operating in bitsliced mode. Furthermore, we prove that no
first-order information leakage is happening in either simulated
power traces and power traces acquired from real hardware,
after sufficient countermeasures are put into place to guard
against pipeline leakages
Using Augmented Reality in Software Engineering Education? First insights to a comparative study of 2D and AR UML modeling
Although there has been much speculation about
the potential of Augmented Reality (AR) in teaching for
learning material, there is a significant lack of empirical
proof about its effectiveness and implementation in
higher education. We describe a software to integrate
AR using the Microsoft Hololens into UML (Unified
Modeling Language) teaching. Its user interface is
laid out to overcome problems of existing software.
We discuss the design of the tool and report a first
evaluation study. The study is based upon effectiveness
as a metric for students performance and components
of motivation. The study was designed as control
group experiment with two groups. The experimental
group had to solve tasks with the help of the AR
modeling tool and the control group used a classic PC
software. We identified tendencies that participants of
the experimental group showed more motivation than
the control group. Both groups performed equally well
Entwicklung eines Manifests für spielifizierte Hochschullehre
In dieser Veröffentlichung präsentieren die Autoren erste Ergebnisse Ihrer Forschungsarbeit an einem Manifest für spielifizierte Hochschullehre. Ausgehend von einer Literaturrecherche über den aktuellen Forschungsstand werden erste Auszüge der aktuellen Arbeit dargestellt, auf deren Basis ein aktiver wissenschaftlicher Diskurs angeregt werden soll
Causality and Functional Safety - How Causal Models Relate to the Automotive Standards ISO 26262, ISO/PAS 21448, and UL 4600
With autonomous driving, the system complexity
of vehicles will increase drastically. This requires new ap-
proaches to ensure system safety. Looking at standards like ISO
26262 or ISO/PAS 21448 and their suggested methodologies,
an increasing trend in the recent literature can be noticed to
incorporate uncertainty. Often this is done by using Bayesian
Networks as a framework to enable probabilistic reasoning.
These models can also be used to represent causal relationships.
Many publications claim to model cause-effect relations, yet
rarely give a formal introduction of the implications and
resulting possibilities such an approach may have. This paper
aims to link the domains of causal reasoning and automotive
system safety by investigating relations between causal models
and approaches like FMEA, FTA, or GSN. First, the famous
“Ladder of Causation” and its implications on causality are
reviewed. Next, we give an informal overview of common
hazard and reliability analysis techniques and associate them
with probabilistic models. Finally, we analyse a mixed-model
methodology called Hybrid Causal Logic, extend its idea, and
build the concept of a causal shell model of automotive system
safety
Security-Gateway for SCADA-Systems in Critical Infrastructures
The presented work is part of the research project Energy
Safe and Secure System Module (ES3M), which is funded by
the Project Management J ̈ulich (PtJ) and the German Federal
Ministry for Economic Affairs and Energy (BMWi) under
funding code 0350042ASupervisory Control and Data Acquisition
(SCADA) systems are used to control and monitor components
within the energy grid, playing a significant role in the
stability of the system. As a part of critical infrastructures,
components in these systems have to fulfill a variety of different
requirements regarding their dependability and must also
undergo strict audit procedures in order to comply with all
relevant standards. This results in a slow adoption of new
functionalities. Due to the emerged threat of cyberattacks
against critical infrastructures, extensive security measures are
needed within these systems to protect them from adversaries
and ensure a stable operation. In this work, a solution is
proposed to integrate extensive security measures into current
systems. By deploying additional security-gateways into the
communication path between two nodes, security features
can be integrated transparently for the existing components.
The developed security-gateway is compliant to all regulatory
requirements and features an internal architecture based on
the separation-of-concerns principle to increase its security
and longevity. The viability of the proposed solution has been
verified in different scenarios, consisting of realistic field tests,
security penetration tests and various performance evaluations