An Online Risk Management Strategy for VoIP Enterprise Infrastructures

Oussema Dabbebi (1) , Rémi Badonnel (1) , Festor Olivier (1)

1 MADYNES - Management of dynamic networks and services

Telephony over IP has known a large-scale deployment which has been supported by the standardization of VoIP signaling and media transfer protocols. This deployment has also led to the emergence of several security threats, including attacks inherited from the IP layer and attacks specific to the application layer. A large variety of security mechanisms has been proposed for addressing them, but these mechanisms may seriously degrade such a critical service. We propose in this paper an online risk management strategy for protecting VoIP infrastructures. The objective is to minimize the network exposure to security attacks while maintaining the quality of service, through the dynamic application of countermeasures. We describe our approach from the formalization of a dedicated risk modelling to its proof-of-concept implementation into an Asterisk VoIP server. We detail a portfolio of countermeasures and evaluate the performance of our solution with respect to different criteria, including the number of countermeasures, the risk threshold and the size of attack signatures.

Mots clés: Risk Management; VoIP Services; Network Management; Security

Domaines: Réseaux et télécommunications [cs.NI]

Oussema Dabbebi, Rémi Badonnel, Festor Olivier. An Online Risk Management Strategy for VoIP Enterprise Infrastructures. [Research Report] 2012, pp.18. ⟨hal-00747585⟩