I had an idea for a simple monotonous (i.e. not absolute) network wide “clock.” The current value of this clock would be sent as one or two extra header fields within the regular SAFE network packets. Nodes would collect the opinion of their close nodes, but they would only distribute what their disjoint section as a whole thinks is the correct time. Basically, disjoint sections would aggregate the time information that is received and filtered by their members, and increase it once it’s plausible that most of the network is already in sync. There would never be a 100% correct value, but it would always be almost sure nobody on the network thinks it’s too much more or too much less than what we ourself think is the current value.
There’s a very badly explained version of this idea somewhere on this forum, but I’m not sure it’s worth reading it. Anyway, I started writing a simulator for it on my day off one or two weeks ago, but I never got to finish it. But it’s coming.