Voice and multimedia content are transmitted across Internet Protocol (IP) networks using VoIP (voice over IP). VoIP is made possible by a collection of technologies and delivery methods for voice communications over wide area networks, enterprise LANs, and the internet. Dedicated desktop VoIP phones, mobile and desktop softphone applications, and WebRTC-capable browsers are examples of VoIP endpoints.

VoIP employs codecs to wrap audio into data packets, transport those packets over an IP network, and then, at the other end of the connection, decapsulate those data packets back into audio. VoIP lowers network infrastructure costs by doing away with the need for circuit-switched networks for voice, enables carriers to deliver phone services via their broadband and private networks, and enables businesses to run a single voice and data network.

The massive operating costs of a traditional telephony infrastructure have been decreased thanks to VoIP. Unfortunately, VoIP services are now being used by cybercriminals, who are posing a number of brand-new problems for law enforcement agencies around the world. Law Enforcement Agencies have benefited greatly from Redback's VoIP investigation methodology and framework in their efforts to stop the abuse of VoIP services.