OpenAI's Realtime API offers advanced capabilities for creating voice experiences that surpass traditional IVRs by allowing live audio streaming to an AI model, which provides intelligent, real-time spoken responses. Bandwidth customers can connect to this API either through Bandwidth's Programmable Voice using bi-directional media streaming with WebSockets or via SIP integration, directly linking Bandwidth SIP trunks to OpenAI. The WebSocket approach provides high control over call behavior, ideal for developers managing custom call flows, while the SIP integration offers a more straightforward setup for SIP-based environments, facilitating direct call routing to OpenAI without the need for WebSocket handling. Both methods enable real-time conversational experiences with OpenAI's models, with the choice between them depending on the required level of control and customization.