Daily's WebRTC calls utilize a signaling server to manage call state in both Peer-to-Peer and Selective Forwarding Unit modes, with the latter also sending and receiving audio and video data between participants. A single server can function as both a signaling server and an SFU in a given region, which is determined by geographic location, potentially impacting latency experienced by call participants. The addition of an EU-based "eu-central-1" region in Frankfurt, Germany offers room and domain owners more control to optimize their participants' call experience. A signaling server acts as an intermediary between two peers, tracking call state information, while an SFU receives all participants' video and audio tracks and forwards them to relevant call participants. Developers can manually toggle between P2P and SFU modes using the API's setNetworkTopology() method, but letting Daily handle these states is often the most efficient option. The location of a signaling server can affect WebRTC call performance, with default settings potentially leading to latency issues for participants in different regions. The introduction of the "eu-central-1" region aims to address GDPR concerns related to transferring call participant data outside of the EU.