7 ms·
I think there should be more focus on latency and upload improvements as well. With all the realtime streaming/communication going on, really low latency is cru
by kayoone 11y ago
I think there should be more focus on latency and upload improvements as well. With all the realtime streaming/communication going on, really low latency is crucial for the future. Also we are sending a lot more data these days, so broadband with 100/6 Mbps or 200/8 Mbps is very unbalanced.
You don't really need more than 25Mbps downstream for streaming even 4K with one client, not uncompressed of course. However 100+ Mbps with <10ms latency allows for real time gaming via streams in high quality for example, making expensive hardware at home obsolete.
- coldtea 11y ago<10ms latency? The speed of limit limit for US coast to coast (Boston to LA) is ~20ms. Roundtrip, since you also need to ask for something, is double that. And that's just the speed of light. Forget <10ms latency as long as physics stand, even for Illinois to California.
- PaulHoule 11y agoTelcos hate low latency. High latency is in their DNA. Nobody has ever been able to sell low latency except to HFT people, and until they started asking, nobody knew what a circuitous route the cables took from Manhattan to New Jersey. The first research project Bell labs did was a test to see how much latency they could get telephone users to tolerate.
- __john 11y ago> The first research project Bell labs did was a test to see how much latency they could get telephone users to tolerate. Do you have a source for that? I genuinely enjoy reading about things like this.
- raverbashing 11y agoI would like to see a source for that, because this makes no sense Latency in analog circuits is a natural product AND very difficult to change either way In digital circuits you might have things adding latency like encoders and filters and some effects of network and packaging of voice data Unless you're blaming AT&T for not being able to go faster than the speed of light
- robotresearcher 11y agoIt makes sense just fine. The research about latency tolerance informed the design constraints for packet-switched digital phone networks, which had been proposed since the 1950s and began to replace POTS in practice in the 1980s (e.g. System X in London in 1980). Latency requirements constrain routing and buffering specs. Packet switched voice could not work until the system could meet human tolerance of latency.
- raverbashing 11y agoWhile that is true, at a certain point, more latency in a working system costs money, especially at the earlier switched systems But yeah, they needed to do a research about it, but I would doubt "The first research project Bell labs did", since Bell Labs predates digital phone networks
- robotresearcher 11y agoSure, but no-one is ever talking about deliberately over-long latency. There's a sweet spot where packet-switched is fast enough, while cheap because of shared bandwidth and routing flexibility. It costs more to go faster, but it's game over to go slower than humans will accept. And it's unlikely that the poster was referring to direct (non-packet) connections since these have been rare for a long time.
- mxuribe 11y agoI agree with __john ; reading about this stuff is cool. Source please?
- avian 11y agoRequirements for 5G are getting equally ridiculous [1]. 5 ms latency and 100 devices per square meter? Whenever I hear something like that, I like to outline a meter by meter of empty floor space and ask people what they imagine 100 devices will be doing in that particular spot. [1] https://5g-ppp.eu/wp-content/uploads/2016/02/BROCHURE_5PPP_BAT2_PL.pdf https://5g-ppp.eu/wp-content/uploads/2016/02/BROCHURE_5PPP_B...
- imaginenore 11y ago100 devices per square meter is normal in tall-ish buildings. Each apartment has 2-3 phones. Offices are even more packed.
- icebraining 11y agoMaybe I'm miscalculating, but I think you're off by an order of magnitude. According to [1], a dense open space office in Manhattan has 100-120ft² per employee; let's take 108ft² which is ~= 10m². That means each m² has ~1/10 of an employee. Even if you multiply by 100 floors, you're only getting ~10 employees/m². [1] http://www.nytimes.com/2015/02/23/nyregion/as-office-space-shrinks-so-does-privacy-for-workers.html?_r=0 http://www.nytimes.com/2015/02/23/nyregion/as-office-space-s...
- veidr 11y agoI think your miscalculation might be devices per person, not people per square meter. My desk area in Tokyo (so maybe not 120ft²; let's call it 60ft²) has a whole lot more devices than people. 4 computers + personal/work phones + 1 watch + 3 tablets + wireless camera + let's say 5 other random items with an IP address that might be paying a visit (think health/fitness devices, teledildonics, wifi-enabled geiger counters, etc.). I may not be typical in April 2016, but I'm also not that much of an outlier. 10+ devices per person seems to be the direction we are heading, so... at 100 floors, yeah 100+ devices per square meter.
- icebraining 11y ago
- imtringued 11y agoWe could always try to put the servers into the center of the USA. Apart from gaming, household to household latency is not particularly important.
- dexterdog 11y agoWhy would you ever have them in one place?
- brador 11y agoCould quantum physics hold the solution? I keep a particle here that I move around and you have it's pair particle on the East coast and watch it wiggle. Somehow turning that into bit flips. Is it feasible?
- adrianN 11y agoFaster than light communication is impossible.
- brador 11y agoIsn't that exactly what Quantum particle pairing solves for?
- roywiggins 11y agoIt does not. At a practical level, you can't "wiggle" one entangled particle to be in any particular classical state without destroying the entanglement. At a theoretical level, the no-communication theorem in quantum mechanics forbids it absolutely: https://en.wikipedia.org/wiki/No-communication_theorem https://en.wikipedia.org/wiki/No-communication_theorem
- KyleBrandt 11y agoReferred to as superluminal communication: https://en.m.wikipedia.org/wiki/Superluminal_communication https://en.m.wikipedia.org/wiki/Superluminal_communication
- pwarner 11y agoLight in fiber travels about 30% slower than in a vacuum. http://physics.stackexchange.com/questions/80043/how-fast-does-light-travel-through-a-fibre-optic-cable http://physics.stackexchange.com/questions/80043/how-fast-do...
- kayoone 11y agoNot unheard of in Europe. I had a connection with <10ms pings to Quake3 Servers in Frankfurt Germany (~300km) 7 years ago.
- coldtea 11y agoWell, obviously, for 300km yes, since light does that in 2ms roundtrip. But that's for stuff mirrored locally like those Quake3 servers. When you get stuff from US datacenters etc you'll suffer even more than 20ms.
- kayoone 11y agoi understand that, just saying that not every country has these insane distances like the US, as even most US content is mirrored on CDNs that are usually pretty close.
- coldtea 11y agoI think the mirrored thing is mostly for assets -- js, images etc. For most smaller websites it's one server somewhere (for the majority of them actually co-hosted with other sites in a single location/box). And for most large websites outside of the very big (e.g. FB and Google), it's at best a few locations around the world, e.g. e.g. US east/west/mid, 1 in Europe, one in Asia, etc, and often even less. So the distances involved do get large there too.
- DiabloD3 11y agoI agree with down being insufficient. I have 15/1. Everything is latency-city compared to everyone else out there. I would literally trade 15/1 for 10/5 if I could, even though that means I would lose SuperHD on Netflix, which is the largest consumer of bandwidth in my house (and virtually Bluray quality when SuperHD is enabled).
- dalore 11y agoYour upstream bandwith isn't your latency. It's how fat your upload is. Swapping 15/1 to 10/5 isn't going to do anything for your latency UNLESS you're already maxing out your upstream.
- DiabloD3 11y agoThat's the problem, I'm on ADSL2. The more upstream bandwidth you use, the worse your latency gets. Let's say I want to stream a multiplayer game. This is now an impossible situation because I barely have enough bandwidth to do a 360p stream as it is. Even if I very carefully keep my upstream bandwidth under 80% utilization, my latency is through the roof. Or let's say an automated off-site sync happens for backups. There goes my latency again. Or I take a photo and upload it. Or I upload music I purchased to Google Music. Or I video chat with someone. So, yes, when you have that little upstream, anything relevant maxes it out and your latency turns to shit.
- dalore 11y agoYou my friend need to to apply some QoS on that ADSL link and have it prioritize the ACK packets to go upstream which is what is killing your latency.
- DiabloD3 11y agoI already use QoS. It does not fix it unless I hard limit upstream to half of my already useless 1mbit. That is not a fix.
- cm2187 11y agoWhat we should really achieve is 1Gbps symmetric connections. Then the cloud is your LAN and then only you can seriously consider working on files stored or backed-up in the cloud. Right now the best upload speed you can get with optic fiber with BT in the UK is 30Mbit. Not a technical limitation, purely a commercial one. I actually don't understand why ISP do not offer better upload speeds. I thought the whole system of peering relied on having balanced upload and download flows, which created problems in datacenters and ISPs, which by nature are one flow only (end users downloading data from datacenters). I would assume both ISP and datacenters would want to encourage having flows the other way, by mean of people backing up their data in the cloud.
- ju-st 11y ago> I actually don't understand why ISP do not offer better upload speeds. ISPs usually have business/enterprise offers with more upload bandwidth for $$$. They don't want to cannibalize this with more upload speed for residential users.
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- diskcat 11y ago>What we should really achieve is 1Gbps symmetric connections. Then the cloud is your LAN jokes on you because my LAN is 100. also im pretty sure all 4 ports on my el cheapo switch are shared.
- fnordfnordfnord 11y agoIf you've got Cat 5 installed, then ~$10 per port can fix that for you.
- bcook 11y agoOn the latency front, CoDel exists for consumer/edge routers. Backbones solve their latency concerns by always having excess bandwidth available. AFAIK, there has been no network queuing advancements that allow for link saturation without multiplicitive latency increases. My 12Mbit/768Kbit ADSL2+ connection has ~15ms latency when idle and ~35ms average (~55ms peak) during upload saturation because of CoDel & traffic-shaping. Without CoDel = ~650ms.
- rharb 11y agoUnbalanced is a nice way to put it :) Our home line is 110/3.5 - if a service can serve content faster than 110 Mbit/s we are limited by the rate at which we can upload the TCP ACK, and not by the download limit on our connection. Another good anecdote: Netflix has been cited as using 9.5% of the internet's upstream traffic on ACK alone. (source: http://arstechnica.com/information-technology/2014/11/netflix-takes-up-9-5-of-upstream-traffic-on-the-north-american-internet/ http://arstechnica.com/information-technology/2014/11/netfli...)
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- _pmf_ 11y ago99 percent of use cases of IoT are data aggregation. Latency is not crucial here; you can still generate precise timestamps on the target side and have a very precise global view even with ridiculously large latency.
- aardshark 11y agoI don't know if you're familiar with Riot Games' infrastructure investments, but I figure it might interest you. They're essentially building their own low-latency network across the US. It's really impressive. https://engineering.riotgames.com/news/fixing-internet-real-time-applications-part-ii https://engineering.riotgames.com/news/fixing-internet-real-...
- kayoone 11y agowow that is super interesting!