In today’s hyper-connected society, everyone constantly uses their smartphone, which in turn uses the commercial cellular networks (from 2G/GSM to 4G/LTE) in order to achieve connectivity. However, contrary to WiFi technology, even most technology-minded people don’t have much of an idea how the infrastructure behind those cellular networks looks like. This talk does not cover the architecture and protocols of underlying cellular systems, but focuses on the physical side of things: what are the typical components of cellular base stations? what are their key functionalities? how did cellular base station technology evolve during the past 20 years? how do we expect cellular base stations to change in the [near] future? We will not cover DIY or hobbyist projects here, but the actual technology deployed in the field by real-world commercial operators. About the speaker: Harald Welte is a CCC member since the 1990ies, developing Free Software for more than 20 years, has a prior life as Linux Kernel developer. He has founded the Osmocom project about 10 years ago and focused his life on implementing cellular protocols, interfaces and network elements as Free Software. about this event: https://c3voc.de