We are looking for an experienced VoIP engineer to configure Kamailio as an SBC together with RTPengine. The goal is to fully rewrite all SIP and RTP traffic so that the upstream provider sees only the public IP of the Kamailio server — no trace of the original Asterisk system. Connection from Asterisk to Kamailio will be over direct IP (SIP trunk), no DNS. Environment (already prepared): Clean Debian 12 (on a dedicated server, not VPS) Kamailio 5.6.3, MariaDB, RTPengine installed Proper DNS and Debian repositories configured SSH access is ready Task Requirements: Configure Kamailio as an SBC for SIP trunk traffic coming from Asterisk Integrate and configure RTPengine for full media relay and SDP rewriting Ensure all SIP headers (From, Contact, Via, etc.) and SDP contain only Kamailio’s public IP No WebRTC, no NAT traversal — standard SIP only Minimal, clean, and secure setup — no extra modules or unused configs (Required): Provide a complete documentation file of the configuration and changes made Deliverables: Fully working configuration tested with sngrep, tcpdump, or similar Configuration files and scripts (if any) stored on the server Written documentation as a separate file (markdown, PDF, or plain text) describing the configuration and steps taken Please include in your application: Your relevant experience with Kamailio/RTPengine/SBC setups Examples of similar work (if available) Estimated time to complete the setup