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Abstract. The Resource Reservation Protocol(RSVP) is a signalling protocol, which transports 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 et al 1986). The methodology includes a service and protocol specification. This paper is focused on the definition, modelling, and analysis of the RSVP service specification. A service language including all the possible service primitives sequences was also generated. It is being used as part of the verification process of RSVP. Also, this service specification will allow other resource reservation protocols to be developed that satisfy this service.

Abstract. The goal of the Resource Reservation Protocol (RSVP) is to establish Quality of Service information within routers and host computers of the Internet. This paper describes a model of RSVP and presents the analysis approach and results. A large part of RSVP is modelled using Coloured Petri Nets. The model provides a clear, unambiguous and precise definition of the considered features of RSVP, which is missing in the current protocol specification. The model is analysed for a set of general properties, such as correct termination, and a set of RSVP specific properties defined in this paper. The properties are checked by querying the state graph and its associated strongly connected component graph. As a first step, we analyse RSVP under the assumption of a perfect medium to ensure that protocol errors are not hidden by rare events of the medium. The results show that the RSVP model satisfies the defined properties.

The goal of the Resource Reservation Protocol (RSVP) is to support the provision of the Quality of Service required for emerging Internet applications (such as video conferencing) that require a level of performance not guaranteed by the Internet. RSVP attempts to provide performance guarantees by establishing resource reservations (such as the number of buffers and bandwidth allocation) within routers and host computers of the Internet. Currently, Internet protocols are not formally specified when they are developed. Instead they are described in a narrative way in documents called Request for Comments(RFCs). This is the case for RSVP. To increase confidence in RSVP we have formalised and analysed its narrative specification using Coloured Petri Nets (CPNs). This paper demonstrates how CPNs can be used for modelling and analysing RSVP. Among the several beneficial features of CPNs are: graphical facilities for specification; support for different levels of abstraction; hierarchical structuring mechanisms; and verification and validation methods, such as querying the state space to investigate properties, and language equivalence to check the consistency of different levels of abstraction. Coloured Petri Nets are supported by a number of computer tools including Design/CPN. Design/CPN supports the construction and maintenance of CPN models and their simulation and analysis using state spaces. These facilities allow us to create a model that provides a clear, unambiguous and precise definition of RSVP, and to analyse the protocol for functional correctness. The paper concentrates on the approach and the tools used in this investigation.