Lecture Notes in Computer Science 3441 CommencedPublicationin1973 FoundingandFormerSeriesEditors: GerhardGoos,JurisHartmanis,andJanvanLeeuwen EditorialBoard DavidHutchison LancasterUniversity,UK TakeoKanade CarnegieMellonUniversity,Pittsburgh,PA,USA JosefKittler UniversityofSurrey,Guildford,UK JonM.Kleinberg CornellUniversity,Ithaca,NY,USA FriedemannMattern ETHZurich,Switzerland JohnC.Mitchell StanfordUniversity,CA,USA MoniNaor WeizmannInstituteofScience,Rehovot,Israel OscarNierstrasz UniversityofBern,Switzerland C.PanduRangan IndianInstituteofTechnology,Madras,India BernhardSteffen UniversityofDortmund,Germany MadhuSudan MassachusettsInstituteofTechnology,MA,USA DemetriTerzopoulos NewYorkUniversity,NY,USA DougTygar UniversityofCalifornia,Berkeley,CA,USA MosheY.Vardi RiceUniversity,Houston,TX,USA GerhardWeikum Max-PlanckInstituteofComputerScience,Saarbruecken,Germany Vladimiro Sassone (Ed.) Foundations of Software Science and Computational Structures 8th International Conference, FOSSACS 2005 Held as Part of the Joint European Conferences onTheoryandPracticeofSoftware,ETAPS2005 Edinburgh, UK, April 4-8, 2005 Proceedings 1 3 VolumeEditor VladimiroSassone UniversityofSussex Dept.ofInformatics BrightonBN19QH,UK E-mail:[email protected] LibraryofCongressControlNumber:Appliedfor CRSubjectClassification(1998):F.3,F.4.2,F.1.1,D.3.3-4,D.2.1 ISSN0302-9743 ISBN3-540-25388-2SpringerBerlinHeidelbergNewYork Thisworkissubjecttocopyright.Allrightsarereserved,whetherthewholeorpartofthematerialis concerned,specificallytherightsoftranslation,reprinting,re-useofillustrations,recitation,broadcasting, reproductiononmicrofilmsorinanyotherway,andstorageindatabanks.Duplicationofthispublication orpartsthereofispermittedonlyundertheprovisionsoftheGermanCopyrightLawofSeptember9,1965, initscurrentversion,andpermissionforusemustalwaysbeobtainedfromSpringer.Violationsareliable toprosecutionundertheGermanCopyrightLaw. SpringerisapartofSpringerScience+BusinessMedia springeronline.com ©Springer-VerlagBerlinHeidelberg2005 PrintedinGermany Typesetting:Camera-readybyauthor,dataconversionbyScientificPublishingServices,Chennai,India Printedonacid-freepaper SPIN:11402060 06/3142 543210 Foreword ETAPS 2005 was the eighth instance of the European Joint Conferences on Theory and Practice of Software. ETAPS is an annual federated conference that was estab- lished in 1998 by combining a number of existing and new conferences. This year it comprisedfiveconferences(CC,ESOP,FASE,FOSSACS,TACAS),17satellitework- shops (AVIS, BYTECODE, CEES, CLASE, CMSB, COCV, FAC, FESCA, FINCO, GCW-DSE,GLPL,LDTA,QAPL,SC,SLAP,TGC,UITP),seveninvitedlectures(not including those that were specific to the satellite events), and several tutorials. We re- ceivedover550submissionstothefiveconferences thisyear,givingacceptance rates below 30% for each one. Congratulations to all the authors who made it to the final program!Ihopethatmostoftheotherauthorsstillfoundawayofparticipatinginthis excitingeventandIhopeyouwillcontinuesubmitting. The events that comprise ETAPS address various aspects of the system develop- ment process, including specification, design, implementation, analysis and improve- ment. The languages, methodologies and tools which support these activities are all well within its scope. Different blends of theory and practice are represented, with an inclination towards theory with a practical motivation on the one hand and soundly based practice on the other. Many of the issues involved in software design apply to systems in general, including hardware systems, and the emphasis on software is not intendedtobeexclusive. ETAPSisalooseconfederationinwhicheacheventretainsitsownidentity,witha separateprogramcommitteeandproceedings.Itsformatisopen-ended,allowingitto grow and evolve as time goes by. Contributed talks and system demonstrations are in synchronizedparallelsessions,withinvitedlecturesinplenarysessions.Twoofthein- vitedlecturesarereservedfor“unifying”talksontopicsofinteresttothewholerangeof ETAPSattendees.Theaimofcrammingallthisactivityintoasingleone-weekmeeting istocreateastrongmagnetforacademicandindustrialresearchersworkingontopics within its scope, giving them the opportunity to learn about research in related areas, andtherebytofosternewandexistinglinksbetweenworkinareasthatwereformerly addressedinseparatemeetings. ETAPS2005wasorganizedbytheSchoolofInformaticsoftheUniversityofEdin- burgh,incooperationwith – EuropeanAssociationforTheoreticalComputerScience(EATCS); – EuropeanAssociationforProgrammingLanguagesandSystems(EAPLS); – EuropeanAssociationofSoftwareScienceandTechnology(EASST). Theorganizingteamcomprised: – Chair:DonSannella – Publicity:DavidAspinall – SatelliteEvents:MassimoFelici – Secretariat:DyaneGoodchild – LocalArrangements:Monika-JeannetteLekuse VI Foreword – Tutorials:AlbertoMomigliano – Finances:IanStark – Website:JenniferTenzer,DanielWinterstein – Fundraising:PhilWadler ETAPS2005receivedsupportfromtheUniversityofEdinburgh. OverallplanningforETAPSconferencesistheresponsibilityofitsSteeringCom- mittee,whosecurrentmembershipis: Perdita Stevens (Edinburgh, Chair), Luca Aceto (Aalborg and Reykjav´ık), Rastislav Bodik (Berkeley), Maura Cerioli (Genoa), Evelyn Duesterwald (IBM,USA),HartmutEhrig(Berlin),Jose´ Fiadeiro(Leicester),Marie-Claude Gaudel (Paris), Roberto Gorrieri (Bologna), Reiko Heckel (Paderborn), Hol- ger Hermanns (Saarbru¨cken), Joost-Pieter Katoen (Aachen), Paul Klint (Am- sterdam), Jens Knoop (Vienna), Kim Larsen (Aalborg), Tiziana Margaria (Dortmund), Ugo Montanari (Pisa), Hanne Riis Nielson (Copenhagen), Fer- nandoOrejas(Barcelona),MoolySagiv(TelAviv),DonSannella(Edinburgh), VladimiroSassone(Sussex),PeterSestoft(Copenhagen),MichelWermelinger (Lisbon),IgorWalukiewicz(Bordeaux),AndreasZeller(Saarbru¨cken),Lenore Zuck(Chicago). Iwouldliketoexpressmysinceregratitudetoallofthesepeopleandorganizations,the programcommitteechairsandPCmembersoftheETAPSconferences,theorganizers of the satellite events, the speakers themselves, the many reviewers, and Springer for agreeingtopublishtheETAPSproceedings.Finally,Iwouldliketothanktheorganizer ofETAPS2005,DonSannella.HehasbeeninstrumentalinthedevelopmentofETAPS sinceitsbeginning;itisquitebeyondthelimitsofwhatmightbeexpectedthat,inad- ditiontoalltheworkhehasdoneastheoriginalETAPSSteeringCommitteeChairman andcurrentETAPSTreasurer,hehasbeenpreparedtotakeonthetaskoforganizingthis instanceofETAPS.ItgivesmeparticularpleasuretothankhimfororganizingETAPS inthiswonderfulcityofEdinburghinthismyfirstyearasETAPSSteeringCommittee Chair. Edinburgh,January2005 PerditaStevens ETAPSSteeringCommitteeChair Preface This volume collects the proceedings of “Foundations of Software Science and Com- putation Structures,” FOSSACS 2005. FOSSACS is a member conference of ETAPS, the “European Joint Conferences on Theory and Practice of Software,” dedicated to foundationalresearchforsoftwarescience.Itinvitessubmissionsontheoriesandmeth- odstounderpintheanalysis,integration,synthesis,transformation,andverificationof programsandsoftwaresystems.Topicscoveredusuallyinclude:algebraicmodels;au- tomata and language theory; behavioral equivalences; categorical models; computa- tionprocessesoverdiscreteandcontinuousdata;computationstructures;logicsofpro- grams;modal,spatial,andtemporallogics;modelsofconcurrent,reactive,distributed, andmobilesystems;modelsofsecurityandtrust;language-basedsecurity;processal- gebras and calculi; semantics of programming languages; software specification and refinement;andtypesystemsandtypetheory. FOSSACS2005consistedofoneinvitedand30contributedpapers,selectedoutof 108submissions,yieldinganacceptancerateoflessthan28%.Thequalityofthemanu- scriptswasveryhighindeed,andtheProgramCommitteehadtorejectseveraldeserving ones.Besidesmakingforastrong2005program,thisisanindicationthatFOSSACSis becominganestablishedpointofreferenceintheinternationallandscapeoftheoretical computerscience.ThisisatrendthatIbelievewillcontinueinitsforthcomingeditions. Besides Marcelo Fiore’s invited talk, the volume includes Ugo Montanari’s in- vitedaddressasanETAPSunifyingspeaker.Ugo’s‘ModelCheckingforNominalCal- culi’reflectsbroadlyontopicsinsemantics,weavingtogetherverificationviasemantic equivalences and model checking, Web services, the π-calculus, and the derivation of bisimulationcongruencesoverreactivesystems.Marcelo’scontribution,‘Mathematical ModelsofComputationalandCombinatorialStructures,’advocatesacombinatorialap- proachtosemanticmodelsbyintroducingacalculusofgeneralizedspeciesofstructures asaunificationandgeneralizationofmodelsarisinginseveraldistinctareas,including hispreviousworkondenotationalmodelsoftheπ-calculusandofvariable-bindingop- erators. The conference program was organized into nine sessions, each focusing on reflectingcommonresearchtopicsamongtheacceptedpapers.Theorderofpresenta- tionofthepapersinthisvolumemaintainsthestructureofthosesessions. IhaveadebtofgratitudetotheProgramCommitteefortheirscholarlyeffortduring the discussion phase; to the referees, for carrying out the reviewing task with compe- tence,care,andprecision;totheinvitedspeakersfortheirinspiredwork;andultimately to the authors for submitting their best work to FOSSACS. Thanks to David Aspinall andDonSannellaforthelocalorganization,andtoMartinKarusseitandTizianaMar- gariafortheirsupportwiththeconferenceelectronicmanagementsystem. Ihopeyouenjoythevolume. Sussex,January2005 VladimiroSassone ProgramChair FOSSACS2005 Organization ProgramCommittee LucaAceto(Aalborg,Denmark) MicheleBugliesi(Venice,Italy) Lu´ısCaires(Lisbon,Portugal) GiuseppeCastagna(ENSParis,France) WitoldCharatonik(Wroclaw,Poland) VincentDanos(PPSParis,France) RobertHarper(CMU,USA) PetrJancˇar(Ostrava,CzechRepublic) NaokiKobayashi(Tokyo,Japan) OrnaKupferman(Jerusalem,Israel) GuyMcCusker(Sussex,UK) UgoMontanari(Pisa,Italy) AncaMuscholl(LIAFAParis,France) TobiasNipkow(Munich,Denmark) AndrewPitts(Cambridge,UK) AmirPnueli(Weizmann,Israeland DavidSands(Chalmers,Sweden) NewYork,USA) VladimiroSassone(Sussex,UK) AndreScedrov(UPenn,USA) PeterSelinger(Ottawa,Canada) WolfgangThomas(Aachen,Denmark) GlynnWinskel(Cambridge,UK) NobukoYoshida(Imperial,UK) Referees ReynaldAffeldt AnaBove PietroDiGianantonio JonathanAldrich TomasBra´zdil Ernst-ErichDoberkat JanAltenbernd ThomasBrihaye MarieDuflot TorbenAmtoft StephenBrookes Mart´ınEscardo´ EugeneAsarin FranckvanBreugel AlessandroFantechi DavidAspinall MarziaBuscemi MarceloFiore FranzBaader MichaelButler RiccardoFocardi ChristelBaier MarcoCarbone AlainFrisch PatrickBaillot JosepCarmona FabioGadducci SebastianBala AlbertoCasagrande PhilippeGaucher PaoloBaldan IlariaCastellani SimonGay RichardBanach AmineChaieb BlaiseGenest NicolasBaudru StefanoChessa NeilGhani GerdBehrmann CorinaCirstea RobvanGlabbeek MartinBerger GiovanniConforti DanieleGorla UlrichBerger ThierryCoquand EricGoubault GerdBerhmann SilviaCrafa JeanGoubault-Larrecq MarcoBernardo KarlCrary SusanneGraf AlexisBes FedericoCrazzolara ErichGra¨del StephenBloom PedroD’Argenio S.Gutierrez-Nolasco RichardBlute JimDavies JoshuaGuttman VivianaBono Jose´eDesharnais PeterHabermehl Organization X MasahitoHasegawa Paul-Andre´ Mellie`s RobertSeely IchiroHasuo RobinMilner RobertoSegala ThomasHildebrandt FaronMoller OlivierSerre DanielHirschkoff LuisMonteiro PeterSewell KoheiHonda CarrollMorgan JanosSimon HaruoHosoya Re´miMorin AlexSimpson JesseHughes MadhavanMukund ChristianSkalka MichaelHuth MarkusMu¨ller-Olm PawełSobocin´ski AtsushiIgarashi SumitNain Jiˇr´ıSrba FlorentJacquemard AleksNanevski IanStark RadhaJagadeesan FrancescoZappaNardelli ColinStirling AlanJeffrey PeterNiebert Marie¨lleStoelinga OleJensen DamianNiwinski KristianStovringSorensen GabrielJuhas GethinNorman OldrichStrazˇovsky´ TomaszJurdzinski KarolOstrovsky EijiroSumii Joost-PieterKatoen SamOwre VascoT.Vasconcelos EmanuelKieronski PrakashPanangaden GabrieleTaentzer BartekKlin GeorgePappas Jean-MarcTalbot TeodorKnapik MatthewParkinson KazushigeTerui MartinKot DoronPeled StavrosTripakis PavelKrcˇa´l FrankPfenning TomaszTruderung NeelKrishnaswami IainPhilipps EmilioTuosto JeanKrivine AndrewPhillips IrekUlidowski JimLaird CarlaPiazza ChristianUrban MartinLange BrigittePientka TarmoUustalu DiegoLatella BenjaminPierce FranckVanBreugel FrancescaLevi Jean-EricPin DanieleVaracca PaulBlainLevy LuciaPomello MariaGraziaVigliotti ChristofLo¨ding K.V.S.Prasad DavidWalker EtienneLozes SanjivaPrasad NicoWallmeier ChristophLu¨th FrancescoRanzato IgorWalukiewicz ZhaohuiLuo JulianRathke VolkerWeber YoadLustig ArendRensink CarstenWeise BasLuttik JamesRiely JoeWells DamianoMacedonio PhilippRohde BenjaminWerner MatteoMaffei BillRoscoe PiotrWieczorek SergioMaffeis SabinaRossi StefanWo¨hrle JeanMairesse PawelRychlikowski BurkhartWolff RupakMajumdar ZdeneˇkSawa JamesWorrell Jean-YvesMarion NorbertSchirmer KwangkeunYi KeyeMartin AlanSchmitt ShojiYuen LuisMateu LutzSchro¨der MarcZeitoun Table of Contents InvitedTalks ModelCheckingforNominalCalculi GianLuigiFerrari,UgoMontanari, EmilioTuosto...................................................... 1 Mathematical Models of Computational and Combinatorial Structures MarceloP.Fiore ................................................... 25 RuleFormatsandBisimulation CongruenceforStructuralCongruences MohammadRezaMousavi,MichelA.Reniers ........................... 47 Probabilistic Congruence for Semistochastic Generative Processes RuggeroLanotte,SimoneTini ........................................ 63 BisimulationonSpeed:AUnifiedApproach GeraldLu¨ttgen,WalterVogler........................................ 79 ProbabilisticModels BranchingCellsasLocalStatesforEventStructuresandNets:Probabilistic Applications SamyAbbes,AlbertBenveniste ....................................... 95 AxiomatizationsforProbabilisticFinite-StateBehaviors YuxinDeng,CatusciaPalamidessi .................................... 110 Stochastic Transition Systems for Continuous State Spaces and Non-determinism Stefano Cattani, Roberto Segala, Marta Kwiatkowska, GethinNorman .................................................... 125 ModelCheckingDurationalProbabilisticSystems Franc¸oisLaroussinie,JeremySproston................................. 140