Ondřej Caletka works as a technical expert in the Learning and Development team of the RIPE NCC. His main responsibility includes developing and operating the lab environment for training courses and online learning.Ondřej graduated from Czech Technical University in Prague and worked as network services administrator and developer for the Czech national research and education network CESNET. He is also active in local IT communities around open source/free software, and acts as an IPv6 and DNSSEC ambassador, delivering talks and trainings at various events.