Modelling and Analysis of the Resource Reservation Protocol Using Coloured Petri Nets

The Internet provides a best-effort transfer service with no service guarantees. Inthe last few years, however, there has been growing interest in providingQuality of Service(QoS) guarantees in the Internet. It has been mainly driven by multimedia and real-timeapplications, which require a certain level of service. Thus, the IETF is working on thedevelopment of new proposals for supporting these applications by improving service quality.They include theInternet Integrated Services and Differentiated Services. In this paper, theyare described and compared in terms of scalability, signalling support, service taxonomy,granularity of service provision, scope of the service, service coordination, and servicedifferentiation. L.2 Conference PapersVillapol M.E. and Billington J.Resource Reservation Protocol for Mobile SatelliteCommunication. Proceedings of 8 International Aerospace Congress (IAC 99) on CD-ROM,September 13-15, 1999, Adelaide, Australia. Abstract. The Internet Engineering Task Force is working on extending the traditionalTCP/IP model for supporting multimedia and real-time applications on the Internet. Thus,new protocols have been developed such as the Resource Reservation Protocol. With therapid growth of mobile networks, the IETF is also working on creating and extending theexisting protocols to support mobile users. This has led to the development of Mobile IP. Atthe same time, there has been a growing interest in using Low Earth Orbit (LEO) satellites.LEO satellites are well suited to providing services to mobile users. In the near future, mobileusers will be able to access multimedia and real-time applications, so the new TCP/IP withreal-time and mobile support will be needed to work over LEO satellite networks. This papersurveys the networking issues related to RSVP over (mobile) LEO satellite networks. It alsodescribes different approaches for extending RSVP for supporting mobile satellite users. The Internet Engineering Task Force is working on extending the traditionalTCP/IP model for supporting multimedia and real-time applications on the Internet. Thus,new protocols have been developed such as the Resource Reservation Protocol. With therapid growth of mobile networks, the IETF is also working on creating and extending theexisting protocols to support mobile users. This has led to the development of Mobile IP. Atthe same time, there has been a growing interest in using Low Earth Orbit (LEO) satellites.LEO satellites are well suited to providing services to mobile users. In the near future, mobileusers will be able to access multimedia and real-time applications, so the new TCP/IP withreal-time and mobile support will be needed to work over LEO satellite networks. This papersurveys the networking issues related to RSVP over (mobile) LEO satellite networks. It alsodescribes different approaches for extending RSVP for supporting mobile satellite users. Appendix L: Publications 339Villapol M.E. and Billington J.RSVP for LEO Satellites, Proceedings of the IEEEInternational Conference on Networks (ICON'99), Brisbane, Australia, September 28 -October 1, 1999, pp 295-302. Abstract. The Internet Engineering Task Force (IETF) is working on extending thetraditional TCP/IP model for supporting multimedia and real-time applications on theInternet. Thus, new protocols have been developed such as the Resource Reservation Protocol(RSVP). At the same time, there has been a growing interest in using Low Earth Orbit (LEO)satellites. In the near future, when the Internet with multimedia and real-time support iswidely deployed, it will need to work over LEO satellite networks. This paper surveys thenetworking issues related to RSVP over LEO satellite networks. It also describes differentapproaches for extending RSVP for supporting satellite users. The Internet Engineering Task Force (IETF) is working on extending thetraditional TCP/IP model for supporting multimedia and real-time applications on theInternet. Thus, new protocols have been developed such as the Resource Reservation Protocol(RSVP). At the same time, there has been a growing interest in using Low Earth Orbit (LEO)satellites. In the near future, when the Internet with multimedia and real-time support iswidely deployed, it will need to work over LEO satellite networks. This paper surveys thenetworking issues related to RSVP over LEO satellite networks. It also describes differentapproaches for extending RSVP for supporting satellite users. Villapol M.E. and Billington J.Modelling and Initial Analysis of the Resource ReservationProtocol using Coloured Petri Nets, Proceedings of the Workshop on Practical Use of High-Level Petri Nets, Aarhus, Denmark, June 27, 2000, pp 91-110. Abstract. The Resource Reservation Protocol (RSVP) conveys Quality of Serviceinformation along the path of a data flow. It is intended to support the new emerging Internetapplications, which require a guaranteed level of service to achieve their functionality. Theaim of this paper is to use Coloured Petri Nets to model some features of the protocol over asimple unicast network. Initial analysis of the model shows that it is working correctly, inother words, as described in RSVP specification document. However, further analyses arerequired to validate the CPN model. The Resource Reservation Protocol (RSVP) conveys Quality of Serviceinformation along the path of a data flow. It is intended to support the new emerging Internetapplications, which require a guaranteed level of service to achieve their functionality. Theaim of this paper is to use Coloured Petri Nets to model some features of the protocol over asimple unicast network. Initial analysis of the model shows that it is working correctly, inother words, as described in RSVP specification document. However, further analyses arerequired to validate the CPN model. Villapol M.E. and Billington J.Generation of a Service Language for the ResourceReservation Protocol Using Formal Methods. Proceedings of Eleventh Annual InternationalSymposium of the International Council On Systems Engineering (INCOSE),on CD-ROM, 1-5 July 2001. Abstract. The Resource Reservation Protocol (RSVP) is a signalling protocol, whichtransports and maintains Quality of Service (QoS) information along the path of a data flow.It is being modelled and analysed using a verification methodology proposed by (Billington etal. 1986). The methodology includes a service and protocol specification. This paper isfocused on the definition, modelling, and analysis of the RSVP service specification. Aservice language including all the possible service primitive sequences was also generated. Itis being used as part of the verification process of RSVP. Also, this service specification willallow other resource reservation protocols to be developed that satisfy this service. The Resource Reservation Protocol (RSVP) is a signalling protocol, whichtransports and maintains Quality of Service (QoS) information along the path of a data flow.It is being modelled and analysed using a verification methodology proposed by (Billington etal. 1986). The methodology includes a service and protocol specification. This paper isfocused on the definition, modelling, and analysis of the RSVP service specification. Aservice language including all the possible service primitive sequences was also generated. Itis being used as part of the verification process of RSVP. Also, this service specification willallow other resource reservation protocols to be developed that satisfy this service. Appendix L: Publications 340Villapol M.E. and Billington J.Techniques and Tools for Formalising and Analysing theResource Reservation Protocol: A Coloured Petri Net Approach. Proceedings of XXVIIILatin-American Conference on Informatics (CLEI 2002), Montevideo, November 25 – 29,2002, on CD-ROM. Abstract. The goal of the Resource Reservation Protocol (RSVP) is to establish Quality ofService information in the form of resource reservations (such as buffers and bandwidth)within routers and host computers of the Internet. It is intended to support emerging Internetapplications that require performance guarantees. Currently, Internet protocols are notformally specified when they are developed. Instead they are described in a narrative way indocuments called Request for Comments (RFCs). This is the case for RSVP. To increaseconfidence in RSVP we have formalised and analysed its narrative specification usingColoured Petri Nets (CPNs). This paper demonstrates how CPNs can be used for modellingand analysing RSVP. Among the several beneficial features of CPNs are: graphical facilitiesfor specification; support for different levels of abstraction; hierarchical structuringmechanisms; and verification and validation methods, such querying the state space toinvestigate properties, and language equivalence to check the consistency of different levelsof abstraction. These facilities allow us to create a model, that provides a clear, unambiguousand precise definition of RSVP, and to analyse the protocol for functional correctness. Thepaper concentrates on the approach and the tools used in this investigation. The goal of the Resource Reservation Protocol (RSVP) is to establish Quality ofService information in the form of resource reservations (such as buffers and bandwidth)within routers and host computers of the Internet. It is intended to support emerging Internetapplications that require performance guarantees. Currently, Internet protocols are notformally specified when they are developed. Instead they are described in a narrative way indocuments called Request for Comments (RFCs). This is the case for RSVP. To increaseconfidence in RSVP we have formalised and analysed its narrative specification usingColoured Petri Nets (CPNs). This paper demonstrates how CPNs can be used for modellingand analysing RSVP. Among the several beneficial features of CPNs are: graphical facilitiesfor specification; support for different levels of abstraction; hierarchical structuringmechanisms; and verification and validation methods, such querying the state space toinvestigate properties, and language equivalence to check the consistency of different levelsof abstraction. These facilities allow us to create a model, that provides a clear, unambiguousand precise definition of RSVP, and to analyse the protocol for functional correctness. Thepaper concentrates on the approach and the tools used in this investigation. Villapol M.E. and Billington.Analysing Properties of the Resource Reservation Protocol.Proceedings of 24th International Conference on Application and Theory of Petri Nets, June23-27, 2003, Eindhoven, The Netherlands, LNCS 2679, pp 377-396. Abstract. The goal of the Resource Reservation Protocol (RSVP) is to establish Quality ofService information within routers and host computers of the Internet. This paper describes amodel of RSVP and presents the analysis approach and results. A large part of RSVP ismodelled using Coloured Petri Nets. The model provides a clear, unambiguous and precisedefinition of the considered features of RSVP, which is missing in the current protocolspecification. The model is analysed for a set of general properties, such as correcttermination, a set of new properties defined in this paper. The properties are checked byquerying the state graph and its associated strongly connected component graph. As a firststep, we analyse RSVP under the assumption of a perfect medium to ensure that protocolerrors are not hidden by rare events of the medium. The results show that the RSVP modelsatisfies the defined properties. The goal of the Resource Reservation Protocol (RSVP) is to establish Quality ofService information within routers and host computers of the Internet. This paper describes amodel of RSVP and presents the analysis approach and results. A large part of RSVP ismodelled using Coloured Petri Nets. The model provides a clear, unambiguous and precisedefinition of the considered features of RSVP, which is missing in the current protocolspecification. The model is analysed for a set of general properties, such as correcttermination, a set of new properties defined in this paper. The properties are checked byquerying the state graph and its associated strongly connected component graph. As a firststep, we analyse RSVP under the assumption of a perfect medium to ensure that protocolerrors are not hidden by rare events of the medium. The results show that the RSVP modelsatisfies the defined properties.