one hurdle for setting up time service: there's a recent vulnerability, NOT yet patched in Debian, that could make the server vulnerable to a DDoS attack. That means I could specifically enable Nikola (fixed IP address) but not Dennis (lappy). So, I could set up my LAN to get time from a London server (via Hedy the Linode), which would work for Dennis-at-home, too; but Dennis-anywhere should use a server selected from a local pool to get something close. I don't know yet if I can then select by stratum... # # #