May 09, 2012, 8:54 PM — Undoubtedly, corporations are realising the benefits of IP voice systems. Voice over internet protocol (VoIP) can bring substantial cost savings and productivity enhancements to a business by transforming its circuit-switched networks to IP packet switching networks and running voice and data applications over a single infrastructure. However, businesses need to be aware that there are potential risks involved, they need to take some necessary steps to protect their interests.
When voice and data are merged onto a single network, voice becomes an application on the network and is, therefore, exposed to the same threats as data applications. These threats include infrastructure and application-based attacks, denial-of-service (DoS) attacks, eavesdropping, toll fraud and protocol-specific attacks. However, with the right procedures in place, VoIP security risks and threats can be managed and mitigated--maximising the benefits of VoIP while minimising exposure.
Infrastructure and application-based attacks
In VoIP, voice is essentially an application on the data network, fine-tuned to maintain voice-quality performance. VoIP equipment and end-point devices such as IP phones are becoming standardised and commoditised just like other data components such as PCs--meaning that VoIP is just as vulnerable to cyber-attacks. Hackers can exploit voice devices and disrupt the network from normal service and/or perform criminal actions such as data theft.
IT managers need to maintain current patch levels on all IT and network equipment and applications, and have appropriate anti-virus software installed and up-to-date. Virtual local area networks (VLANs) can also be implemented and used to protect voice traffic from data network attacks. By implementing application gateways between trusted and untrusted zones of the network, a VLAN will complement the protection offered by corporate firewalls.
Denial-of-service (DoS) attacks
A DoS attack occurs when someone deliberately floods a particular network with so much illegitimate traffic that it blocks legitimate traffic. Obviously, if your voice traffic is being transmitted over the same network, a DoS attack will have significant impact on business operations.
DoS attacks are difficult to stop and prevent, but proper intrusion prevention practices, special network devices and proper patch updates can minimise the risk of exposure. In order to prevent data network problems from affecting voice traffic, voice and data traffic should logically be separated from administrative traffic. Traffic shaping can also provide another layer of protection and control for the network.