ScottyG wrote: > Thanks everyone for pointing out the, let call it silliness of this > requirement. Also thanks for all your quick responses. > > I went back to the traders who defined this requirement. They do > seem to think that they know what they want, it's just not what they > are asking for. From my talks with them, the main goal is to be able > to unravel what happened when a set of trades fail. > > To do this the order in which market data was received and trades > transmitted need to be maintained. I do know from their current log > files that 1 ms is not fine enough for this and that on occasion .1 > ms is not good enough. They currently are using a feature of the > processors that seems to return clock tick on the microprocessor > (Some assembly language instruction). They have an algorithm for > controlling the skew that occurs using this method. This seems to > meet there needs in a single server scenario but when going across > machines this will obviously not work. > > What I would like to do is go back to them with reasonable > expectations. > > What do you think you can achieve with let say 5,000-10,000 USD > budget for each data center? Could we get 1 micro, 10 micro, 100 > micro, 1 milli? > > One catch is the not all the data centers have access to roof space > for us. One company claims that they can use CDMA as a source time. > Does anyone know the implications of this? It seems that the time > would be sourced from GPS and retransmitted via the cell towers. To > me this brings up more potential delays but I am not an expert. > > Scott > >
The reference signal from a CDMA cell phone base station contains extremely accurate timing information. There are commercially available devices that can obtain the time from such a signal. The base station obtains timing information from a GPS receiver. _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
