RTP Traffic Obfuscation

Our company is committed in providing only the Open standards for algorithms, protocols and codes. However, there is a small exception that the RTP traffic Obfuscation technology may make the ZRTP and SRTP traffic appear like a non-standard, non-recognized VoIP protocol. It is required because in some countries Voice over IP protocol and, in particular, RTP and unencrypted SIP traffic, are detected and blocked.

By using a custom and proprietary obfuscation technology, PrivateGSM will works even when VoIP protocols are blocked by using DPI (Deep Packet Inspection) systems.

The obfuscation technology is designed in a way so that any UDP packet, before being sent to the network, is processed by a customer filter that “scrambles” the RTP header and RTP payload in order not to be blocked. The opposite process is applied on the receiving side, de-obfuscating the RTP obfuscated packet before being processed.

Further, PrivateWave provides if needed a custom Obfuscation/De-obfuscation Proxy server that a customer can install in front of a Secure PBX. It yields the whole RTP traffic hiding process transparent, regardless the software used to run the PBX.

PrivateGSM Professional and Government by default obfuscate ZRTP traffic while while the obfuscation is disabled by default in PrivateGSM Enterprise.

The protocol feature it’s configurable by the user in Advanced Settings of the application, allowing the user to enable or disable it depending on the network configuration.

N.B.: Obfuscation is a sort of scrambling and does not add any security feature. It is used to avoid VoIP blocking filters applied on the network