Netnod runs time sources on behalf of the Swedish Post and Telecom Authority (PTS). This is implemented as distributed clocks in five different locations. From these clocks Netnod provides several services: frequency, PTP and NTP, including signed NTP, both the older symmetric NTPv4 and the new NTS.
NTP is provided through a novel hardware (FPGA) implementation commissioned by Netnod.
NTP is inherently insecure. Netnod has been involved in trying to make it less so through the development of NTS protocol in IETF and implementing it in Python and Go. We offer as a proof-of-concept one of the world's first NTS servers traceable to Swedish official time.