Jim Salter at Ars Technica, back in the days, used to do some good tests: https://arstechnica.com/gadgets/2016/09/the-router-rumble-ars-diy-build-faces-better-tests-tougher-competition/ And Plume used to have a real test house back then, as well: https://arstechnica.com/gadgets/2017/02/going-hands-on-and-behind-the-scenes-at-the-plume-wi-fi-hq/2/ All the best, Frank Frantisek (Frank) Borsik https://www.linkedin.com/in/frantisekborsik Signal, Telegram, WhatsApp: +421919416714 iMessage, mobile: +420775230885 Skype: casioa5302ca frantisek.borsik@gmail.com On Mon, Sep 2, 2024 at 7:29 PM Bob McMahon via Bloat < bloat@lists.bufferbloat.net> wrote: > This is David's experience. It doesn't extrapolate to the industry. Our > testing as a component supplier is quite extensive. The level of math > required likely equals ML. The table stakes for a 2 BSS system with hidden > nodes, etc is $80K. That's just equipment. Then test engineers with deep > expertise of 802.11 have to be hired. And they have to continuously learn > as 802.11 is a living standard. And now they need to learn CCAs and network > marking planes. Then this all has to be paid for typically through > component sells as there are no software SKUs. > > The cadences for new ASICs is 24 months. The cadences for OSP upgrades is > 10 to 20 years. > > Of course testing is under funded. No stock b.s. to pay the bills. It has > to come from discounted cash flows. > > Everyone wants the experts to work for free. Iperf2 is that already. I > don't see any more freebies on the horizon. > > Bob > > On Sun, Sep 1, 2024, 10:05 PM David Lang via Make-wifi-fast < > make-wifi-fast@lists.bufferbloat.net> wrote: > >> On Sun, 1 Sep 2024, Hal Murray via Make-wifi-fast wrote: >> >> > David Lang said: >> >> It really doesn't help that everyone in the industry is pushing for >> >> higher bandwidth for a single host. That's a nice benchmark number, >> but >> >> not really relevant int he real world. >> > >> >> Even mu-mimo is of limited use as most routers only handle a handful of >> >> clients. >> > >> >> But the biggest problem is just the push to use wider channels and gain >> >> efficiency in long-running bulk transfers by bundling lots of IP >> packets >> >> into a single transmission. This works well when you don't have >> >> congestion and have a small number of clients. But when you have lots >> of >> >> clients, spanning many generations of wifi technology, you need to go >> to >> >> narrower channels, but more separate routers to maximize the fairness >> of >> >> available airtime. >> > >> > What does that say about the minimal collection of gear required in a >> test >> > lab? >> > >> > If you had a lab with plenty of gear, what tests would you run? >> >> I'll start off by saying that my experience is from practical >> in-the-field uses, >> deploying wifi to support thousands of users in a conference setting. >> It's >> possible that some people are doing the tests I describe below in their >> labs, >> but from the way routers and wifi standards are advertised and the guides >> to >> deploy them are written, it doesn't seem like they are. >> >> My belief is that most of the tests are done in relatively clean RF >> environments >> where only the devices on the test network exist, and they can always >> hear >> everyone on the network. In such environments, everything about existing >> wifi >> standards and the push for higher bandwidth channels makes a lot of sense >> (there >> are still some latency problems) >> >> But the world outside the lab is far more complex >> >> you need to simulate a dispursed, congested RF environment. This includes >> hidden >> transmitters (stations A-B-C where B can hear A and C but A and C cannot >> hear >> each other), dealing with weak signals (already covered), interactions of >> independent networks on the same channels (a-b and c-d that cannot talk >> to each >> other), legacy equipment on the network (as slow as 802.11g at least, if >> not >> 802.11b to simulate old IoT devices), and a mix of bulk-transfers >> (download/uploads), buffered streaming (constant traffic, but buffered so >> not >> super-sentitive to latency), unbuffered streaming (low bandwidth, but >> sensitive >> to latency), and short, latency sensitive traffic (things that block >> other >> traffic until they are answered, like DNS, http cache checks, http main >> pages >> that they pull lots of other URLs, etc) >> >> test large number of people in a given area (start with an all wireless >> office, >> then move on to classroom density), test not just one room, but multiple >> rooms >> that partially hear each other (the amount of attenuation or reflection >> between >> the rooms needs to vary). The ultimate density test would be a >> stadium-type >> setting where you have rows of chairs, but not tables and everyone is >> trying to >> livestream (or view a livestream) at once. >> >> Test not just the ultra-wide bandwidth with a single AP in the rooms, but >> narrower channels with multiple APs distributed around the rooms. Test >> APs >> positioned high, and set to high power to have large coverage areas >> against APs >> positioned low (signals get absorbed by people, so channels can be reused >> at >> shorter distances) and set to low power (microcell approach). Test APs >> overhead >> with directional antennas so they cover a small footprint. >> >> Test with different types of walls around/between the rooms, metal studs >> and >> sheetrock of a modern office have very little affect on signals, >> stone/brick >> walls of old buildings (and concrete walls in some areas of new >> buildings) >> absorb the signal, the metal grid in movable air walls blocks and >> reflects >> signals >> >> Remember that these are operating in 'unlicensed' spectrum, and so you >> can have >> other devices operating here as well causing periodic interference (which >> could >> show up as short segments of corruption or just an increased noise >> floor). >> Current wifi standards interpret any failed signals as a weak signal, so >> they >> drop down to a slower modulation or increasing power in the hope of >> getting the >> signal through. If the problem is actually interference from other >> devices >> (especially other APs that it can't decipher), the result is that all >> stations >> end up yelling slowly to try and get through and the result is very high >> levels >> of noise and no messages getting through. Somehow, the systems should >> detect >> that the noise floor is high and/or that there is other stuff happening >> on the >> network that they can hear, but not necessarily decipher and switch away >> from >> the 'weak signal' mode of operation (which is appropriate in sparse >> environments), and instead work to talk faster and at lower power to try >> and >> reduce the overall interference while still getting their signal through. >> (it does no good for one station to be transmitting at 3w while the >> station it's >> talking to is transmitting at 50mw). As far as I know, there is currently >> no way >> for stations to signal what power they are using (and the effective power >> would >> be modified by the antenna system, both transmitted and received), so >> this may >> be that something like 'I'm transmitting at 50% of my max and I hear you >> at 30% >> with noise at 10%' <-> 'I'm transmitting at 100% of my max and I hear you >> at 80% >> woth noise at 30%' could cause the first station to cut down on it's >> power until >> the two are hearing each other at similar levels (pure speculation here, >> suggestion for research ideas) >> >> > How many different tests would it take to give reasonable coverage? >> >> That's hard for me to say, and not every device needs to go through every >> test. >> But when working on a new standard, it needs to go through a lot of these >> tests, >> the most important ones IMHO are how they work with a high density of >> users >> accessing multiple routers which are distributed so there is overlapping >> coverage and include a mix of network traffic. >> >> David Lang >> _______________________________________________ >> Make-wifi-fast mailing list >> Make-wifi-fast@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/make-wifi-fast > > > This electronic communication and the information and any files > transmitted with it, or attached to it, are confidential and are intended > solely for the use of the individual or entity to whom it is addressed and > may contain information that is confidential, legally privileged, protected > by privacy laws, or otherwise restricted from disclosure to anyone else. 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