Voice over Internet Protocol (VoIP) or, as the acronym is often pronounced, voyp is the future of voice services. Today, an increasing number of the voice calls you make are converted to VoIP for the in-the-network parts of your calls, because VoIP is more flexible, less expensive, and more efficient in terms of network utilization. But that's really just the beginning. VoIP is becoming more common as an end-to-end service and moving beyond just voice calls into other media, such as video conferencing, IM and text chat, file and screen sharing, and more. As with any newer technology, the adoption of VoIP comes with some unique challenges security risks, implementation and interoperability headaches, and emerging services. But, Session Border Controllers in IP Multimedia Subsystem, is here to help with timely information about session border controllers (SBCs): devices designed to control the calls (or videoconferencing, or other media) coming in and out of an enterprise's or service provider's VoIP network, while also handling the signaling and media intermedia-tion and translation required to make the VoIP service work smoothly all the time.