Lars Degenhardt

Managing IT infrastructure: firewall administration, network management (VLANs, routing, enterprise switches), Proxmox virtualization, and TrueNAS storage. Supporting FreeSWITCH integration and WebRTC projects. Building and maintaining OpenSIPS installations. Experience with innovaphone PBX systems (iPVAs).

VoIP system integration and interoperability testing with customer systems, Deutsche Telekom, and Telekom Austria (A1). Worked with Teles VoIP switches, AudioCodes gateways, and Vierling ECOTEL VoIP-to-cellular gateways (based on Yate and SER/SuSE Linux) with centralized SIM Card Server (SCS) for mobile traffic cost optimization. On-site deployments at client locations in Switzerland and England (Teles switches) and Bulgaria (SIM servers). Deployed Oreka/OrkAudio for VoIP call recording, including a stadium security control center. Projects using Asterisk and later primarily FreeSWITCH as PBX platform. Deployed Zarafa as groupware solution. Consistently delivering IPsec-based VPN solutions.

Started in the support department — nicknamed "die Pinguine" (after Tux, the Linux mascot). Worked on BenHur, the world's first Linux-based multifunctional communication server. Kernel patching to integrate HiSax/mISDN drivers for Cologne Chip HFC-based ISDN hardware and multilink PPP over ISDN. Sendmail configuration using m4 macros and hand-edited sendmail.cf. Integrated FreeS/WAN, later Openswan and strongSwan for IPsec VPN functionality, including interoperability testing with the IPsec client from Finnish company SSH.com. Represented Pyramid at trade shows including CeBIT (Hanover), LinuxTag (Stuttgart), and an IT trade show in Cologne, where he served as a panelist on IT security. Gradually took on development responsibilities alongside the support team.