36,691 research outputs found
Eliminating Network Protocol Vulnerabilities Through Abstraction and Systems Language Design
Incorrect implementations of network protocol message specifications affect
the stability, security, and cost of network system development. Most
implementation defects fall into one of three categories of well defined
message constraints. However, the general process of constructing network
protocol stacks and systems does not capture these categorical con- straints.
We introduce a systems programming language with new abstractions that capture
these constraints. Safe and efficient implementations of standard message
handling operations are synthesized by our compiler, and whole-program analysis
is used to ensure constraints are never violated. We present language examples
using the OpenFlow protocol
Safety of Lithium Nickel Cobalt Aluminum Oxide Battery Packs in Transit Bus Applications
The future of mass transportation is clearly moving toward the increased efficiency and greenhouse gas reduction of hybrid and electric vehicles. With the introduction of high-power/high-energy storage devices such as lithium ion battery systems serving as a key element in the system, valid safety and security concerns emerge. This is especially true when the attractive high-specific-energy and power-chemistry lithium nickel cobalt aluminum oxide (NCA) is used. This chemistry provides great performance but presents a safety and security risk when used in large quantities, such as for a large passenger bus. If triggered, the cell can completely fuel its own fire, and this triggering event occurs more easily than one may think.
To assist engineers and technicians in this transfer from the use of primarily fossil fuels to battery energy storage on passenger buses, the Battery Application Technology Testing and Energy Research Laboratory (BATTERY) of the Thomas D. Larson Pennsylvania Transportation Institute (LTI) in the College of Engineering at The Pennsylvania State University partnered with advanced chemistry battery and material manufacturers to study the safety concerns of an NCA battery chemistry for use in transit buses. The research team ran various experiments on cells and modules, studying rarely considered thermal events or venting events. Special considerations were made to gather supporting information to help better understand what happens, and most importantly how to best mitigate these events and/or manage them when they occur on a passenger bus.
The research team found that the greatest safety concern when using such a high-energy chemistry is ensuring passenger safety when a cellĂąâŹâąs electrolyte boils and causes the ventilation of high-temperature toxic material. A cell-venting event can be triggered by a variety of scenarios with differing levels of likelihood. Also, though the duration of a venting event is relatively short, on the order of just a few seconds, the temperature of the venting material and cell is extremely high. During a venting event, the high-pressure, burning gases tend to burn holes in nearby packaging materials. Most interestingly, the team discovered that following a venting event the large-format cells tested immediately reached and remained at extremely high external skin temperatures for very long periods, on the order of hours. The majority of this report covers the testing designed to better understand how high-energy cells of this chemistry fail and what materials can be used to manage these failures in a way that increases passenger survivability
Towards Model Checking Real-World Software-Defined Networks (version with appendix)
In software-defined networks (SDN), a controller program is in charge of
deploying diverse network functionality across a large number of switches, but
this comes at a great risk: deploying buggy controller code could result in
network and service disruption and security loopholes. The automatic detection
of bugs or, even better, verification of their absence is thus most desirable,
yet the size of the network and the complexity of the controller makes this a
challenging undertaking. In this paper we propose MOCS, a highly expressive,
optimised SDN model that allows capturing subtle real-world bugs, in a
reasonable amount of time. This is achieved by (1) analysing the model for
possible partial order reductions, (2) statically pre-computing packet
equivalence classes and (3) indexing packets and rules that exist in the model.
We demonstrate its superiority compared to the state of the art in terms of
expressivity, by providing examples of realistic bugs that a prototype
implementation of MOCS in UPPAAL caught, and performance/scalability, by
running examples on various sizes of network topologies, highlighting the
importance of our abstractions and optimisations
Validating a Web Service Security Abstraction by Typing
An XML web service is, to a first approximation, an RPC service in which
requests and responses are encoded in XML as SOAP envelopes, and transported
over HTTP. We consider the problem of authenticating requests and responses at
the SOAP-level, rather than relying on transport-level security. We propose a
security abstraction, inspired by earlier work on secure RPC, in which the
methods exported by a web service are annotated with one of three security
levels: none, authenticated, or both authenticated and encrypted. We model our
abstraction as an object calculus with primitives for defining and calling web
services. We describe the semantics of our object calculus by translating to a
lower-level language with primitives for message passing and cryptography. To
validate our semantics, we embed correspondence assertions that specify the
correct authentication of requests and responses. By appeal to the type theory
for cryptographic protocols of Gordon and Jeffrey's Cryptyc, we verify the
correspondence assertions simply by typing. Finally, we describe an
implementation of our semantics via custom SOAP headers.Comment: 44 pages. A preliminary version appears in the Proceedings of the
Workshop on XML Security 2002, pp. 18-29, November 200
ITERL: A Wireless Adaptive System for Efficient Road Lighting
This work presents the development and construction of an adaptive street lighting system
that improves safety at intersections, which is the result of applying low-power Internet of Things
(IoT) techniques to intelligent transportation systems. A set of wireless sensor nodes using the
Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 standard with additional internet
protocol (IP) connectivity measures both ambient conditions and vehicle transit. These measurements
are sent to a coordinator node that collects and passes them to a local controller, which then makes
decisions leading to the streetlight being turned on and its illumination level controlled. Streetlights
are autonomous, powered by photovoltaic energy, and wirelessly connected, achieving a high degree
of energy efficiency. Relevant data are also sent to the highway conservation center, allowing it to
maintain up-to-date information for the system, enabling preventive maintenance.ConsejerĂa de Fomento y Vivienda Junta de AndalucĂa G-GI3002 / IDIOFondo Europeo de Desarrollo Regional G-GI3002 / IDI
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