Results 1  10
of
12
A Calculus of Broadcasting Systems
 SCIENCE OF COMPUTER PROGRAMMING
, 1991
"... CBS is a simple and natural CCSlike calculus where processes speak one at a time and are heard instantaneously by all others. Speech is autonomous, contention between speakers being resolved nondeterministically, but hearing only happens when someone else speaks. Observationally meaningful laws dif ..."
Abstract

Cited by 64 (8 self)
 Add to MetaCart
CBS is a simple and natural CCSlike calculus where processes speak one at a time and are heard instantaneously by all others. Speech is autonomous, contention between speakers being resolved nondeterministically, but hearing only happens when someone else speaks. Observationally meaningful laws differ from those of CCS. The change from handshake communication in CCS to broadcast in CBS permits several advances. (1) Priority, which attaches only to autonomous actions, is simply added to CBS in contrast to CCS, where such actions are the result of communication. (2) A CBS simulator runs a process by returning a list of values it broadcasts. This permits a powerful combination, CBS with the host language. It yields several elegant algorithms. Only processes with a unique response to each input are needed in practice, so weak bisimulation is a congruence. (3) CBS subsystems are interfaced by translators; by mapping messages to silence, these can restrict hearing and hide speech. Reversi...
Formalizing Process Algebraic Verifications in the Calculus of Constructions
"... This paper reports on the first steps towards the formal verification of correctness proofs of reallife protocols in process algebra. We show that proofs can be verified, and partly constructed, by a general purpose proof checker. The process algebra we use is µCRL, ACP augmented with data, wh ..."
Abstract

Cited by 18 (7 self)
 Add to MetaCart
This paper reports on the first steps towards the formal verification of correctness proofs of reallife protocols in process algebra. We show that proofs can be verified, and partly constructed, by a general purpose proof checker. The process algebra we use is µCRL, ACP augmented with data, which is small enough to make the verification feasible, and at the same time expressive enough for the specification of reallife protocols. The proof checker we use is Coq, which is based on the Calculus of Constructions, an extension of simply typed lambda calculus. The focus is on the translation of the proof theory of µCRL and µCRLspecifications to Coq. As a case study, we verified the Alternating Bit Protocol.
Proof Principles for Datatypes with Iterated Recursion
, 1997
"... . Data types like trees which are finitely branching and of (possibly) infinite depth are described by iterating initial algebras and terminal coalgebras. We study proof principles for such data types in the context of categorical logic, following and extending the approach of [14, 15]. The technica ..."
Abstract

Cited by 17 (3 self)
 Add to MetaCart
. Data types like trees which are finitely branching and of (possibly) infinite depth are described by iterating initial algebras and terminal coalgebras. We study proof principles for such data types in the context of categorical logic, following and extending the approach of [14, 15]. The technical contribution of this paper involves a description of initial algebras and terminal coalgebras in total categories of fibrations for lifted "datafunctors". These lifted functors are used to formulate our proof principles. We test these principles by proving some elementary results for four kinds of trees (with finite or infinite breadth or depth) using the proof tool pvs. 1 Introduction Algebras and coalgebras are of wellestablished importance in computer science, notably in the theory of datatypes, where especially initial algebras and terminal coalgebras play a distinguished role. Over the past decade there is more and more interest in the logic associated with initial algebras and ter...
Coalgebraic Theories of Sequences in PVS
, 1998
"... This paper explains the setting of an extensive formalisation of the theory of sequences (finite and infinite lists of elements of some data type) in the Prototype Verification System pvs. This formalisation is based on the characterisation of sequences as a final coalgebra, which is used as an axi ..."
Abstract

Cited by 8 (2 self)
 Add to MetaCart
This paper explains the setting of an extensive formalisation of the theory of sequences (finite and infinite lists of elements of some data type) in the Prototype Verification System pvs. This formalisation is based on the characterisation of sequences as a final coalgebra, which is used as an axiom. The resulting theories comprise standard operations on sequences like composition (or concatenation), filtering, flattening, and their properties. They also involve the prefix ordering and proofs that sequences form an algebraic complete partial order. The finality axiom gives rise to various reasoning principles, like bisimulation, simulation, invariance, and induction for admissible predicates. Most of the proofs of equality statements are based on bisimulations, and most of the proofs of prefix order statements use simulations. Some significant aspects of these theories are described in detail. This coalgebraic formalisation of sequences is presented as a concrete example that shows t...
Themes in Final Semantics
 Dipartimento di Informatica, Università di
, 1998
"... C'era una volta un re seduto in canap`e, che disse alla regina raccontami una storia. La regina cominci`o: "C'era una volta un re seduto in canap`e ..."
Abstract

Cited by 6 (2 self)
 Add to MetaCart
(Show Context)
C'era una volta un re seduto in canap`e, che disse alla regina raccontami una storia. La regina cominci`o: &quot;C'era una volta un re seduto in canap`e
The Coq Proof Assistant  Reference Manual Version 6.1
, 1997
"... : Coq is a proof assistant based on a higherorder logic allowing powerful definitions of functions. Coq V6.1 is available by anonymous ftp at ftp.inria.fr:/INRIA/Projects/coq/V6.1 and ftp.enslyon.fr:/pub/LIP/COQ/V6.1 Keywords: Coq, Proof Assistant, Formal Proofs, Calculus of Inductives Constru ..."
Abstract

Cited by 2 (0 self)
 Add to MetaCart
: Coq is a proof assistant based on a higherorder logic allowing powerful definitions of functions. Coq V6.1 is available by anonymous ftp at ftp.inria.fr:/INRIA/Projects/coq/V6.1 and ftp.enslyon.fr:/pub/LIP/COQ/V6.1 Keywords: Coq, Proof Assistant, Formal Proofs, Calculus of Inductives Constructions (R'esum'e : tsvp) This research was partly supported by ESPRIT Basic Research Action "Types" and by the GDR "Programmation " cofinanced by MREPRC and CNRS. Unit'e de recherche INRIA Rocquencourt Domaine de Voluceau, Rocquencourt, BP 105, 78153 LE CHESNAY Cedex (France) T'el'ephone : (33 1) 39 63 55 11  T'el'ecopie : (33 1) 39 63 53 30 Manuel de r'ef'erence du syst`eme Coq version V6.1 R'esum'e : Coq est un syst`eme permettant le d'eveloppement et la v'erification de preuves formelles dans une logique d'ordre sup'erieure incluant un riche langage de d'efinitions de fonctions. Ce document constitue le manuel de r'ef'erence de la version V6.1 qui est distribu 'ee par ftp ...
Prototyping Processes
 Proc. of AGP'99  Joint Conference on Declarative Programming
, 1999
"... Construction and observation are two basic notions in Computer Science corresponding to precise dual mathematical concepts: those of algebra and coalgebra. This paper introduces a simple coalgebraic model for concurrent processes and discusses its animation in the declarative language Charity. I ..."
Abstract

Cited by 2 (2 self)
 Add to MetaCart
(Show Context)
Construction and observation are two basic notions in Computer Science corresponding to precise dual mathematical concepts: those of algebra and coalgebra. This paper introduces a simple coalgebraic model for concurrent processes and discusses its animation in the declarative language Charity. It is argued that the ability to reason in an uniform way about data and behaviour, provides an unifying approach to functional prototyping of software specifications. Keywords: Coalgebraic models, prototyping, higherorder programming. 1
Formal Verification of Communication Protocol Using Type Theory
, 2003
"... In this paper, an approach is proposed to verify communication protocol using the type theoretical proof assistant Coq. Compared with existing methods of protocol verification, this approach is based directly on the simple notion of event trace. Without the burden of embedding external concurrent la ..."
Abstract
 Add to MetaCart
(Show Context)
In this paper, an approach is proposed to verify communication protocol using the type theoretical proof assistant Coq. Compared with existing methods of protocol verification, this approach is based directly on the simple notion of event trace. Without the burden of embedding external concurrent languages such as process algebra, finite state machine, temporal logic, etc., this approach leads to very efficient reasoning. The approach is deliberately designed to exploit the computational mechanism intrinsic to type theory so that many cases can be proved automatically by computation.