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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

#91

Post by throwaway2048 »

jrockway wrote: post #64

This technology will also be excellent for games. Right now, the server has to decide how it's going to break ties, and that results in confusing moments. For example, Overwatch favors the shooter, so you might see someone in a position to shoot you, use a defensive ability, and die even though you used it, because the server decides that if two events are close in time, the shooter wins. With a trusted time referenc…

You still cant trust the client here, no matter how precisely synced your clocks are, because it could maliciously reorder events/tamper with time (always claim you activated first, with a certain fudge factor to prevent detection) and it would be undetectable within the bounds of internet latency.

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

#92

Post by [deleted] »

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…

[deleted]

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

#93

Post by geofft »

zeth___ wrote: post #86
geofft wrote: post #48

Earlier quoted context omitted.

Not an expert so I might be totally off, but I think one of the risks is the existence of alternative markets. Let's say you're only allowed to trade once a week, and I buy a bunch of Hooli stock at, say, $25 today. Then they launch Yet Another Hooli Chat tomorrow and everyone has decided that's going to make the price go up. You might want to buy some shares at $27 right now, because you think they'll be worth $30 n…

How is that different to the current alternative dark pools?

Dark pools are a special case of this phenomenon, yes, but they're different from regular stock exchanges precisely because they're dark. Some market participants prefer them, and some don't. But a hypothetical "light pool" would be strictly preferable to NASDAQ-but-weekly - it's almost always in every participant's individual interest to trade immediately instead of waiting up to a week and randomly getting orders filled or not.

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

#94

Post by gsich »

simias wrote: post #15
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…

I can't imagine how you could hope to reach nanosecond-precision over the internet without changing all the routing hardware in use today. With PTP you can already reach sub-microsecond synchronization but you need full hardware support for every network element on the route if you want to achieve that. The timestamping is done on the network PHY itself, which is how you can remove all jitter introduced by the kernel…

You usually have full hardware support, at least if you are using intel nics.

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

#95

Post by gsich »

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.

You need to get the PPS to some other device, then it could be done. The whole GPS stratum 1 thing is mostly just PPS. You get the correct time with ntp, and the start of a second with the PPS from the GPS.

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

#96

Post by physguy1123 »

ISL wrote: post #74
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…

I'm a slow trader -- a few trades a year. I like, or at least don't mind, HFT. It certainly doesn't hurt liquidity. There is, in principle, always someone who wants to trade with me, and the increased volume may make price-discovery a little more accurate. When I place a limit order, I don't mind at all if someone has managed to front-run my order and sell it to me at the price I set. I got the thing I wanted to buy…

I'm pretty sure you misunderstand market orders because by definition they are only visible to the market after they have traded, so nobody can get ahead of you or do sonething irrational before your order lands.

I would agree that market orders are a bad idea at any meaningful volume (outaide of retail sizes) because of liquidity and routing reasons

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

#97

Post by arcticfox »

qeternity wrote: post #77
physguy1123 wrote: post #62

Earlier quoted context omitted.

Vanguard states that hft activities have lowered their trading costs, so I don't think this claim is necesarily true.

HFT has reduced costs under 99.99% of market environments. My direct cost and slippage is still so much lower than it would have been 30 years ago. Hell, even 10 years ago.

Where would the profits that go to HFT outfits go if HFT wasn't a thing? Genuine question, I have no idea how that works.

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

#98

Post by physguy1123 »

arcticfox wrote: post #97
qeternity wrote: post #77

Earlier quoted context omitted.

HFT has reduced costs under 99.99% of market environments. My direct cost and slippage is still so much lower than it would have been 30 years ago. Hell, even 10 years ago.

Where would the profits that go to HFT outfits go if HFT wasn't a thing? Genuine question, I have no idea how that works.

They would go to whomever else was marker makers, whomever else was doing short-term trading, and some of fhe rest to quant firms doing frequent but not hft trading.

Mostly human traders/market makers in short.

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

#99

Post by monch1962 »

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…

Bear in mind that exchanges are owned by the companies that trade on them - they've got a VERY strong vested interest in not fixing the problem.

HFT works because fast traders can see a buy and sell order that are a distance apart, buy from the seller, then immediately offer to sell it at a fractionally higher price. Because they can see the buy order at all times, they know they can sell what they've just bought and make a tiny profit. All they have to do is ensure they can see the buy and sell orders faster than anyone else, then keep hitting those orders. Repeat until retirement.

Several years ago, a new exchange was set up to try to address this problem by simply putting a huge coil (many km) of fibre in front of the system/s that accepted orders. This approach meant that, while HFTs could still see orders before anyone else and hit them faster, their speed advantage was largely lost due to the latency as their order placement was just a bit slower. As a result there was no guarantee the 2nd part of the order those HFTs were hitting was still there, so they might get left holding a position without being able to sell it at the profit they were used to. Each HFT could try to front run orders as they do now, but the fairly small increase in latency killed their advantage.

HFT companies managed to avoid using this exchange very successfully.

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