SIP Interface has expanded its support to include international regions such as North America, Europe, Asia Pacific, and South America, enabling users to specify the region closest to their communications infrastructure for optimal service quality when sending or receiving SIP traffic through Twilio. To utilize this feature, users can update their IP address whitelist and point their communications infrastructure to Twilio's localized URIs or include a region parameter in their SIP URI. This expansion allows developers to easily add cloud voice capabilities to their existing VoIP infrastructure without costly upgrades or hardware purchases, enabling features such as WebRTC capabilities on top of an existing IP PBX or call center.