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Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

nytimes.com

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Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#51

Post by dagenix »

downer68 wrote: post #45
dagenix wrote: post #6

Earlier quoted context omitted.

Are you saying that 64 bit CPU + 64 bit CPU = 128 bit CPU (as long as they are time synced)? 1. It doesn't work this way 2. Why would you want a 4096 bit CPU?

I don't know how you found your way onto the addition operator (+) on your keyboard, because that's not at all what I was driving at. I think you are... JUMPING! TO CONCLUSIONS! (get it?) Anyway, at it's core, much of the logic within a turing machine winds up being addition in an accumulator. So, you widen the pipeline, and that adds place settings to the numeric values addressed at a location in RAM. I think we bot…

I'm having a hard time trying to figure out if you are serious or if you are masterfully trolling everyone.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#52

Post by bcaa7f3a8bbc »

wmf wrote: post #19
bcaa7f3a8bbc wrote: post #4

It is great news if this algorithm can work directly on the public Internet, without requiring a specialized network - many scientific and engineering applications will be able to get its time reference directly from the Internet! NTP and other protocols currently used are unauthenticated (there is NTP autokey, etc, but its security properties are not ideal, and mostly not deployed) and it is a big security hole, esp…

It would probably be more accurate to install a stratum 1 NTP server on your phone since it has GPS. But then you'd probably get hit with jitter from Wi-Fi/Bluetooth/USB.

BTW, it's trivial to build a WWVB receiver nowadays, and a Rubidium standard only costs 200 USD.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#53

Post by geofft »

mlichvar wrote: post #36
geofft wrote: post #5

This looks like a paper about the Huygens system, with comparison to other protocols like PTP: https://www.usenix.org/system/files/conference/nsdi18/nsdi18... Also these slides: https://platformlab.stanford.edu/Seminar%20Talks/retreat-201...

I maintain an NTP implementation. That comparison doesn't seem fair to me. It looks like they are comparing the old reference NTP implementation and not really the protocol itself. An NTP implementation can certainly synchronize clocks with better accuracy than 1 millisecond, or even 1 microsecond with hardware timestamping and good network switches. There are some interesting ideas in the Huygens paper, but I don't…

The other thing I don't understand is that this paper argues against hardware timestamping on the grounds that users won't want to buy expensive hardware, and that Huygens is for "standard hardware ... in current data centers". Expensive, niche hardware is normal for the HFT folks that care about nanosecond precision.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#54

Post by grzm »

downer68 wrote: post #47
downer68 wrote: post #45

Earlier quoted context omitted.

I don't know how you found your way onto the addition operator (+) on your keyboard, because that's not at all what I was driving at. I think you are... JUMPING! TO CONCLUSIONS! (get it?) Anyway, at it's core, much of the logic within a turing machine winds up being addition in an accumulator. So, you widen the pipeline, and that adds place settings to the numeric values addressed at a location in RAM. I think we bot…

Good job, guys! Nice downvotes! Real nice! I answered substantively, addressing each point carefully, and I was pleasantly rewarded for the time I took to respond. Great incentive system you guys have worked out! Glad to see it being used as intended! Works like a charm!

You were likely down-voted for the snark with which you addressed the points.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#55

Post by davrosthedalek »

makomk wrote: post #8
bcaa7f3a8bbc wrote: post #4

It is great news if this algorithm can work directly on the public Internet, without requiring a specialized network - many scientific and engineering applications will be able to get its time reference directly from the Internet! NTP and other protocols currently used are unauthenticated (there is NTP autokey, etc, but its security properties are not ideal, and mostly not deployed) and it is a big security hole, esp…

If I'm understanding the Huygens paper linked in one of the other comments correctly, this is strictly in-datacenter only; it relies on properties of datacenter networking that don't apply to the broader internet, in particular that routes are mostly symmetric and mostly low-latency.

Haven't read the paper yet, but even it is data-center only, it is still very relevant for science, e.g. DAQ in nuclear physics, especially if it doesn't need custom hardware.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#57

Post by acover »

chaboud wrote: post #20

"So-called high frequency trading firms place trades in a fraction of a second, sometimes in a bet that they can move faster than bigger competitors." First off: no. Big money plays in high frequency trading (roughly half of all trading activity), and the smaller traders without instantaneous access are the losers in this game. Secondly, NASDAQ's obsession with precise global sequencing is A) misguided and B) effecti…

This doesn't solve the problem. There are multiple exchanges. If a real time exchange experiences a price drop then you could quickly sell stock on the quantized exchange with the hope of being randomly chosen.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#59

Post by karpodiem »

qeternity wrote: post #24
chaboud wrote: post #20

"So-called high frequency trading firms place trades in a fraction of a second, sometimes in a bet that they can move faster than bigger competitors." First off: no. Big money plays in high frequency trading (roughly half of all trading activity), and the smaller traders without instantaneous access are the losers in this game. Secondly, NASDAQ's obsession with precise global sequencing is A) misguided and B) effecti…

Most HFT shops are relatively small. HFT is all about latency and turn over. Big quant shops might have HFT elements but lean far more towards systematic/algo strategies that can be relatively high latency (still super low latency, but not HFT) because these are the only strategies that you can deploy serious var with. The guys crushing HFT are not huge hedge funds, and they are solving more engineering problems than…

"Also, no, small traders don't lose. Retail traders et al get much tighter spreads, cheaper execution by routing to internalizers, etc."

There's liquidity until there isn't. It was easier to get an order filled during a run to the exit pre-HFT. When everyone runs to the exit in an HFT world, retail investors are the last to get their orders filled, if they're lucky.

Re: Google and Nasdaq Pursuing Nano-Second Precision in Network Time Protocol

#60

Post by amenod »

From [0]:

> In this paper, we present HUYGENS, a software clock synchronization system that uses a synchronization network and leverages three key ideas. First, coded probes identify and reject impure probe data—data captured by probes which suffer queuing delays, random jitter, and NIC timestamp noise. Next, HUYGENS processes the purified data with Support Vector Machines, a widely-used and powerful classifier, to accurately estimate one-way propagation times and achieve clock synchronization to within 100 nanoseconds. Finally, HUYGENS exploits a natural network effect—the idea that a group of pair-wise synchronized clocks must be transitively synchronized— to detect and correct synchronization errors even further.

Not an expert, but this seems quite a complex system. Since HF traders have huge incentive to game the system, my fear is that the next headline about Huygens will be about a new exploit found in the wild.

[0] https://www.usenix.org/conference/nsdi18/presentation/geng

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