Verification of the Capability Exchange Signalling protocol

  • Lin Liu
  • Jonathan Billington
Special Section CPN 04/05


The Capability Exchange Signalling (CES) protocol is one of the sub-protocols of recommendation H.245, “Control protocol for multimedia communication” issued by the International Telecommunication Union. In this paper, we model the CES protocol with Coloured Petri Nets and verify it using state space and language analyses. The results reveal that the CES protocol could fail when the sequence numbers used by the protocol wrap. To solve this problem, we propose a set of changes to the CES protocol. State space and language analyses are then applied to the revised protocol. Verification results suggest that the revised protocol satisfies the desired properties with the errors discovered being eliminated.


Protocol verification Coloured Petri Nets Capability Exchange Signalling protocol State space analysis Language equivalence 


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.School of Computer and Information ScienceUniversity of South AustraliaAdelaideAustralia
  2. 2.Computer Systems Engineering Centre, School of Electrical and Information EngineeringUniversity of South AustraliaMawson LakesAustralia

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