180,248 research outputs found
Improving Runtime Overheads for detectEr
We design monitor optimisations for detectEr, a runtime-verification tool
synthesising systems of concurrent monitors from correctness properties for
Erlang programs. We implement these optimisations as part of the existing tool
and show that they yield considerably lower runtime overheads when compared to
the unoptimised monitor synthesis.Comment: In Proceedings FESCA 2015, arXiv:1503.0437
Distributed Enforcement of Service Choreographies
Modern service-oriented systems are often built by reusing, and composing
together, existing services distributed over the Internet. Service choreography
is a possible form of service composition whose goal is to specify the
interactions among participant services from a global perspective. In this
paper, we formalize a method for the distributed and automated enforcement of
service choreographies, and prove its correctness with respect to the
realization of the specified choreography. The formalized method is implemented
as part of a model-based tool chain released to support the development of
choreography-based systems within the EU CHOReOS project. We illustrate our
method at work on a distributed social proximity network scenario.Comment: In Proceedings FOCLASA 2014, arXiv:1502.0315
On the Automated Synthesis of Enterprise Integration Patterns to Adapt Choreography-based Distributed Systems
The Future Internet is becoming a reality, providing a large-scale computing
environments where a virtually infinite number of available services can be
composed so to fit users' needs. Modern service-oriented applications will be
more and more often built by reusing and assembling distributed services. A key
enabler for this vision is then the ability to automatically compose and
dynamically coordinate software services. Service choreographies are an
emergent Service Engineering (SE) approach to compose together and coordinate
services in a distributed way. When mismatching third-party services are to be
composed, obtaining the distributed coordination and adaptation logic required
to suitably realize a choreography is a non-trivial and error prone task.
Automatic support is then needed. In this direction, this paper leverages
previous work on the automatic synthesis of choreography-based systems, and
describes our preliminary steps towards exploiting Enterprise Integration
Patterns to deal with a form of choreography adaptation.Comment: In Proceedings FOCLASA 2015, arXiv:1512.0694
Verification and Synthesis of Symmetric Uni-Rings for Leads-To Properties
This paper investigates the verification and synthesis of parameterized
protocols that satisfy leadsto properties on symmetric
unidirectional rings (a.k.a. uni-rings) of deterministic and constant-space
processes under no fairness and interleaving semantics, where and are
global state predicates. First, we show that verifying for
parameterized protocols on symmetric uni-rings is undecidable, even for
deterministic and constant-space processes, and conjunctive state predicates.
Then, we show that surprisingly synthesizing symmetric uni-ring protocols that
satisfy is actually decidable. We identify necessary and
sufficient conditions for the decidability of synthesis based on which we
devise a sound and complete polynomial-time algorithm that takes the predicates
and , and automatically generates a parameterized protocol that
satisfies for unbounded (but finite) ring sizes. Moreover, we
present some decidability results for cases where leadsto is required from
multiple distinct predicates to different predicates. To demonstrate
the practicality of our synthesis method, we synthesize some parameterized
protocols, including agreement and parity protocols
Synthesis of Distributed Longitudinal Control Protocols for a Platoon of Autonomous Vehicles
We develop a framework for control protocol synthesis for a platoon of autonomous vehicles subject to temporal logic specifications. We describe the desired behavior of the platoon in a set of linear temporal logic formulas, such as collision avoidance, close spacing or comfortability. The problem of decomposing a global specification for the platoon into distributed specification for each pair of adjacent vehicles is hard to solve. We use the invariant specifications to tackle this problem and the decomposition is proved to be scalable.. Based on the specifications in Assumption/Guarantee form, we can construct a two-player game (between the vehicle and its closest leader) locally to automatically synthesize a controller protocol for each vehicle. Simulation example for a distributed vehicles control problem is also shown
Fuzzy-logic-based control, filtering, and fault detection for networked systems: A Survey
This paper is concerned with the overview of the recent progress in fuzzy-logic-based filtering, control, and fault detection problems. First, the network technologies are introduced, the networked control systems are categorized from the aspects of fieldbuses and industrial Ethernets, the necessity of utilizing the fuzzy logic is justified, and the network-induced phenomena are discussed. Then, the fuzzy logic control strategies are reviewed in great detail. Special attention is given to the thorough examination on the latest results for fuzzy PID control, fuzzy adaptive control, and fuzzy tracking control problems. Furthermore, recent advances
on the fuzzy-logic-based filtering and fault detection problems are reviewed. Finally, conclusions are given and some possible future research directions are pointed out, for example, topics on two-dimensional networked systems, wireless networked control systems, Quality-of-Service (QoS) of networked systems, and fuzzy access control in open networked systems.This work was supported in part by the National Natural Science Foundation of China under Grants 61329301,
61374039, 61473163, and 61374127, the Hujiang Foundation of China under Grants C14002 andD15009, the Engineering and Physical Sciences Research Council (EPSRC) of the UK, the Royal Society of the UK, and the Alexander von Humboldt Foundation of Germany
Applying Formal Methods to Networking: Theory, Techniques and Applications
Despite its great importance, modern network infrastructure is remarkable for
the lack of rigor in its engineering. The Internet which began as a research
experiment was never designed to handle the users and applications it hosts
today. The lack of formalization of the Internet architecture meant limited
abstractions and modularity, especially for the control and management planes,
thus requiring for every new need a new protocol built from scratch. This led
to an unwieldy ossified Internet architecture resistant to any attempts at
formal verification, and an Internet culture where expediency and pragmatism
are favored over formal correctness. Fortunately, recent work in the space of
clean slate Internet design---especially, the software defined networking (SDN)
paradigm---offers the Internet community another chance to develop the right
kind of architecture and abstractions. This has also led to a great resurgence
in interest of applying formal methods to specification, verification, and
synthesis of networking protocols and applications. In this paper, we present a
self-contained tutorial of the formidable amount of work that has been done in
formal methods, and present a survey of its applications to networking.Comment: 30 pages, submitted to IEEE Communications Surveys and Tutorial
Parameterized Synthesis
We study the synthesis problem for distributed architectures with a
parametric number of finite-state components. Parameterized specifications
arise naturally in a synthesis setting, but thus far it was unclear how to
detect realizability and how to perform synthesis in a parameterized setting.
Using a classical result from verification, we show that for a class of
specifications in indexed LTL\X, parameterized synthesis in token ring networks
is equivalent to distributed synthesis in a network consisting of a few copies
of a single process. Adapting a well-known result from distributed synthesis,
we show that the latter problem is undecidable. We describe a semi-decision
procedure for the parameterized synthesis problem in token rings, based on
bounded synthesis. We extend the approach to parameterized synthesis in
token-passing networks with arbitrary topologies, and show applicability on a
simple case study. Finally, we sketch a general framework for parameterized
synthesis based on cutoffs and other parameterized verification techniques.Comment: Extended version of TACAS 2012 paper, 29 page
Automated Synthesis of Distributed Self-Stabilizing Protocols
In this paper, we introduce an SMT-based method that automatically
synthesizes a distributed self-stabilizing protocol from a given high-level
specification and network topology. Unlike existing approaches, where synthesis
algorithms require the explicit description of the set of legitimate states,
our technique only needs the temporal behavior of the protocol. We extend our
approach to synthesize ideal-stabilizing protocols, where every state is
legitimate. We also extend our technique to synthesize monotonic-stabilizing
protocols, where during recovery, each process can execute an most once one
action. Our proposed methods are fully implemented and we report successful
synthesis of well-known protocols such as Dijkstra's token ring, a
self-stabilizing version of Raymond's mutual exclusion algorithm,
ideal-stabilizing leader election and local mutual exclusion, as well as
monotonic-stabilizing maximal independent set and distributed Grundy coloring
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