From peer into my NIC [assuming a very fast switch so that its time is negligable], less than 20 microseconds.Quote from Swan Noir:
Nitro, at what point do you consider it low latency in your terms?
Most people prefer to measure "end to end": from market data =>NIC , and NIC <= order data. So
Peer MD=>NIC=>Trading Algo=>Order=>NIC=>Peer
From NIC to NIC. Doing it from Peer to Peer requires nano/micro synchronization of clocks that is not so trivial to do.
But this has nothing to do with retail trading. In that scenario, probably 250 Millis is fine. In other words, a THOUSAND times worse than I am willing to tolerate in an arbitrage situation.