Development and design of carrier-grade all-over-ip and IMS/NGN-solutions (Voice, Video and more), product- and technical design, requirements engineering, deep protocol knowledge of IP oriented protocols (SIP, RTP, SDP, RTSP, ...). Knowledge of VoIP-Scalability/Development/Security. Experience with big installations.
Experience with project-management and consulting.
Heavy programming experiences in C/C++ and PHP.
Experiences with many Open-Source-solutions like sip-router.org (aka. OpenSER/Kamailio/SER, member of the development-team), Asterisk, mySQL.
Specialties: SIP, VoIP, IMS, NGN, IPTV, Quad-Play