Programmable network devices configured to perform various UPF functions including QoS enforcement, session management, and timer synchronization. Field-programmable gate arrays (FPGAs) are configured to perform user plane functions on data streams within a compact and modular hardware unit to minimize excessive communication while maintaining control and user plane separation (CUPS). QoS enforcement can include guaranteed bit rate (GBR) and maximum bit rate (MBR) and token buckets associated therewith, pipeline processing, synchronizing transmission of data packets and control signals with timers at various operational levels, and so on.