Design and validation of computer protocols
Design and validation of computer protocols
Coloured Petri nets (2nd ed.): basic concepts, analysis methods and practical use: volume 1
Coloured Petri nets (2nd ed.): basic concepts, analysis methods and practical use: volume 1
Coloured Petri Nets and CPN Tools for modelling and validation of concurrent systems
International Journal on Software Tools for Technology Transfer (STTT)
PETRI NETS '08 Proceedings of the 29th international conference on Applications and Theory of Petri Nets
A formally verified mechanism for countering SPIT
CRITIS'10 Proceedings of the 5th international conference on Critical Information Infrastructures Security
| Hi-index | 0.00 |
The Session Initiation Protocol (SIP) is one of the leading protocols for multimedia control over the Internet, including initiating, maintaining and terminating multimedia sessions. The protocol uses transactions to complete the control tasks. In this paper we focus on the INVITE transaction of SIP, which is used to initiate a session. SIP is designed to operate over a transport protocol that can be reliable or unreliable. Our previous work has verified the functional properties of the INVITE transaction over a reliable transport medium, using Coloured Petri Nets (CPNs). In this paper, we use CPNs to model and analyse SIP INVITE transaction when the medium is unreliable. The verification reveals similar problem as that in the case of a reliable medium, i.e. the transaction may terminate in an undesirable state while one communication party is still waiting for a response from its peer. Additionally with an unreliable medium, the transaction has undesirable terminal states in which retransmitted requests may lead to erroneous operation. This result provides theoretical evidence and timely support for the Internet Draft that has been recently submitted to the Internet Engineering Task Force to propose updates to SIP INVITE transaction.