Hacker News new | past | comments | ask | show | jobs | submit login
Avery’s laws of Wi-Fi reliability (apenwarr.ca)
170 points by colinprince on July 11, 2017 | hide | past | favorite | 84 comments



This is a good insight, especially the diagram at the top. But the quesion for me is, why is a router broken say 10% of the time?

I think the problem is that WiFi is totally undebuggable. When it doesn't work, you don't see at which stage it doesn't work.

- Do the frames in the air get corrupted or dropped? What portion of frames makes it through?

- I see the SSID, so it can transmit something. Why can't I connect and get at least a slow connection?

- What is it doing now, sending, waiting for a response, did it negotiate encryption yet?

- Is the low-level connection OK, and we have a problem with DHCP? This you can detect, but the OS obscures it from you.

- There is no easy way to see signal strength. You get a more or less meaningful number reported from the card, but these nice diagrams showing signal strength over frequency? Mostly fake, this is just the reported signal strength of each channel, smoothed out to look like a continuous scan. If we had a continuous scan, we could see individual sources of interference better.

- Why does the connection suddenly drop out or get slow? Is the problem on my side of the router, or on the internet side? Are buffers full/empty? Is some object standing in the way, or is is a weather phenomenon? You can ping your router or modem, and some routers have nice tools to let you see graphs of upstream and downstream. But there is no coherent debugging solution.


>But the quesion for me is, why is a router broken say 10% of the time?

From a lot of experience, I see these issues.

All in one router/wireless/NAT/switch units: Doing too much at the lowest price. The fact wi-fi has stopped working is really secondary to some memory leak in the system eating up resources causing problems with the entire unit. Solution: Separate switching, routing, and wireless access point capability. Reliability goes up (unless you buy really terrible equipment), each individual system has less responsibilities and less potential bug interaction.

Access points: Wireless has the problem of trying to be everything to everyone. Just look at how many different wireless protocols are enabled at one time by default. G, N, A, AC, likely over 2 different spectrums. Individually this are complex protocols, all together it leads to stuff breaking. Even worse you're dealing with exceptionally secretive vendors (Yes, that means you Broadcom), so getting good chip information is hard. Solution: Enable only one standard and then only use one client chipset in all your clients (heh, pretty much impossible).

Wireless itself: The first rule of wireless is, the less wireless you have, the better. I have clients that can pick up between 30 and 50 access points at any given time. Needless to say, wireless is useless for them. Other non wi-fi devices on the same spectrum pretty much ruin reliable transfers. Also people blasting their wireless power and over coverage. This is where I would say the article is wrong. More AP units are better, as long as there is as little overlap as possible between stations. 3 small station areas will work better than one large area with random dead spots and long distances between clients (hidden node problem).

Power: Many routers/AP have crappy power input. Swapping out their power brick with something more reliable helps often, unless they have crappy caps on board.


> why is a router broken say 10% of the time?

My guess would be that WiFi drivers are kind of quirky - if you follow OpenWRT/LEDE development there a lot of issues that appear only on heavy load or under certain situations - causes range from driver bugs / chip bugs / firmware bugs - most of the stuff is NDA or closed source. You've got the problem on both sides - especially the situation on Linux is still dire for lot's of chipsets. Even my years old intel card in my notebook does not really work well with Linux und the current kernel/firmware. I blame the vendors.

> Do the frames in the air get corrupted or dropped? What portion of frames makes it through?

That also depends on the rate and encoding that the frames are sent. Then there is stuff like frame aggretation that sometimes work sometimes not.

> I see the SSID, so it can transmit something. Why can't I connect and get at least a slow connection?

SSID is send with the lowest rate (1Mbit) and with the most solid encoding - usally the transmit power and antenna sensitivity is also the strongest on the lowest rate so the SSID can be seen quite far away - often so far away that your clients wifi is able to receive the SSID beacons but unable to send something back that reaches the router.

> What is it doing now, sending, waiting for a response, did it negotiate encryption yet?

Wrong crypto results in no association - difficult to tell apart from low signal.

> Is the low-level connection OK, and we have a problem with DHCP? This you can detect, but the OS obscures it from you.

Yes. You can look at network-manager logs from Linux but sometimes it's difficult to tell - especially on Windows.

> There is no easy way to see signal strength.

There is also noise, antenna properties and everything depends on the rate and encoding used - it's not exactly easy.

> Why does the connection suddenly drop out or get slow?

Add also the rate control algorithms, the amount of clients, for certain 5GHz channels you have to obey radar then there is interference with bluetooth and microwaves. Also all that funky physics stuff with reflection and antenna positioning where moving a little bit might be just enough to cause problems for you.


> SSID is send with the lowest rate (1Mbit) and with the most solid encoding - usally the transmit power and antenna sensitivity is also the strongest on the lowest rate so the SSID can be seen quite far away - often so far away that your clients wifi is able to receive the SSID beacons but unable to send something back that reaches the router.

Thats what I mean. It would be great if you could click "debug", and it says "Receiving beacons from router, but router is not responding to frames".

Maybe it would even be smart enough to do a back-of-the-envelope calculation if details about the router are known, e.g. router transmits with X watt, the recieved signal strength is Y. I can transmit with Z watt, so the router should / should not be able to hear me.

Then it could suggest "You have to move closer to the router, use a better antenna, or increase power to the antenna (reduces battery life)". Nowadays you don't get anything, not even an error message. It silently stops connecting on most platforms, and the WiFi symbol slightly changes.


Wouldn't you be able to debug some of these issues using a packet sniffer ?

http://www.networkcomputing.com/networking/wifi-troubleshoot...


Yes, all the stuff mentioned is totally debuggable, done it many times, but it takes time to sift through the packets.


This. It's incredibly frustrating on my phone to see 40 seconds of "Requesting IP address..." and then it goes back to "Connecting...". WTF was that? DHCP is the easy part!


If the packets get through, DHCP is easy. If packets are being lost, not so easy.


- Is it the DNS? 90% of my wifi problems at work and in hotels are solved with DNS 8.8.8.8., which is sad because clients have full access to internet, except it doesn't work.


Personally I think a big problem are all these 3 in 1 type modem/router/wifi solutions and the inability to debug which part is causing problems. These devices a less expensive but seem to always compromise some functionality. What that is, is rarely evident from the box/review/manual.

For a long time now, I've always recommend to people to buy standalone cable/DSL modems and figure out how to get the analog signal strength/error correction/retry counters from them (and return it if you can't get them). Then spend the time replacing connectors in your house and getting the modem as close to the curb as possible.

Then pick a good wifi solution, and tweak that until its as clean as possible. Wifi and modem standards evolve at different paces, and its silly to upgrade your modem or router every time you want a newer wifi standard, or for that matter change your wifi to get a newer cable or DSL modem.


Or just buy something of quality like AVM Fritz!Box, which has quite good diagnose utilities on board


It depends. The Fritzboxes that were sold in Australia had an ADSL chipset in them that wasn't very good at handling noisy lines (you're very, very lucky if yours isn't). Your best bet is/was to buy a device with a particular Broadcom chipset in it that was good at handling noise. The difference it made to my connection speed was from syncing at 4 megabit downstream to syncing at 10 megabit downstream. This steadily degraded to 8 megabit over the next few years, but what are you gonna do?


1. Replacing your router (or firmware) almost always fixes your problem.

2. Adding an additional router almost always makes things worse.

Solution: Switch off nodes when they stop working.

My house has this problem. I live on the 4th floor, next to the main VDSL router. The kitchen & living room on the 2nd floor can't get a strong WiFi signal. After some thought about WiFi repeaters, I decided to buy a long Ethernet wire and run it down the stairs. I trip over it sometimes, but it's basically reliable. The downstairs router runs dd-wrt, and works fine 99% of the time (I've had to reboot it once in the past year).

The upstairs VDSL router is owned by the telecom company (Chunghwa), and they don't give me administrator access. I can't change the firmware, and the box is frankly awful. About 6 months ago we complained repeatedly, asking them to replace the box. They sent tech guys, who tested the wire, and said that everything is fine. Indeed, it works about 70% of the time. But very often I come home from work, and I have to reboot that router before I can get online.

My solution is to buy a Edimax WiFi power socket and a Raspberry Pi, which checks to see if it's online. When the network goes down for more than a minute, it'll automatically tell the WiFi power socket to turn the router off and on again.

I know that power-cycling is bad for the router, but I don't see any other solution given the software constraints. I'm also surprised that there are no companies making devices for the purpose of power-cycling routers.


Megatec make a few devices for power cycling routers: http://www.megatec.com.tw/info.htm

I've not tried one and at around $75 they aren't cheap. I was looking into them at a time when my cable modem would forget how to route anything and need to be power cycled, but replacing it did the trick.


Here's another one: http://resetplug.com/

And here's one that resets based on a timer rather than Wifi signal: http://www.netreset.com/

And another one that uses ethernet: https://www.amazon.com/3Gstore-Remote-Power-IP-Switch/dp/B01...


Thank you so much for finding existing products! I'm certainly going to buy one of these.

ResetPlug is for WiFi, but hasn't posted anything since 2016 (I'm a bit worried that it might not exist any more).

Megatec ezPower is in Taiwan (local for me), but is only Ethernet. Often the Ethernet still works even when the WiFi doesn't, so I'll try to get the ResetPlug first.


I am both awed and dismayed that this is a thing.


My parents just used one of those old school mechanical socket timers and had it shut down for 5 minutes every morning at 4 AM. Might not work for you if you have long-running connections you need to maintain...


2. Adding an additional router almost always makes things worse.

While I wouldn't add another router, I've found that adding additional AP's almost always makes things better, assuming they are not on overlapping channels.


I've seen Google Wi-Fi installations where someone adds three APs in a tiny urban apartment, and removing one actually improves signal and throughput.


I've had that happen, the trick is to place them on the other side of large metal objects (like in rooms behind fridges) or with as many walls between them as possible. It really does come down to placement and how many Wi-Fi hotspots your neighbours run. It's theoretically possible that your 3 Wi-Fi hotspots could run at channels 1, 6 and 11, and try to pin devices to each channel, while still working in one room. But if you've limited Wi-Fi spectrum available, adding more APs isn't going to help things unless they're carefully tuned to transmit with less power/interference.


Except when for some reason roaming don't work for that certain device during full moon. Or after power outage it will boot but not properly and router will work and AP won't. Or AP kinda works, WiFi part at least but there is no internet there for whatever reason. In my case it is a clear case of multiplying problems.


If you have a strong enough signal that adding a new AP is not neccessary, then you don't need to roam. If you have multiple AP's and can't roam between them, you're no worse off than if you had one.

If you have malfunctioning hardware, then you're going to have problems whether you have one AP or multiple AP's -- use better hardware.


How warm is it at your place? I've been quite successful avoiding router lock ups by adding some active cooling: take an old PC fan, solder it to the power wires of an old USB cable, connect that cable to the router (assuming your router has an active USB port).


Taiwan: so hot right now. 32ºC in the day, 26ºC at night.

I've often speculated that the temperature is causing problems, which would also explain why it's hard to reproduce the issue when a telecom service tech comes over. I'll have a look around for a suitable fan, and see if that helps.


I did this on one of my APs that fails frequently (locks up and the front lights go off, signal strength randomly goes down to about 8 feet with no obstructions, etc) and it helped immensely. unfortunately, it didn't /solve/ the problem for me, just made it better. I've ordered some unifi stuff on recommendation from friends. hopefully that'll live up to the hype and do the job.


I decided to buy a long Ethernet wire and run it down the stairs. I trip over it sometimes,

Why not use Powerline Ethernet? In most houses, it's typically fast and reliable and requires no extra wires. E.g. the data rate between my desk and router is currently 784 Mbit/s.


Powerline is a crapshoot, at least as much as Wifi. I installed several different models a few years back, for me and some friends/family, and in every case ended up finding another solution as they would just add another layer of unreliability.

Cheap ones suffer from the same problems as cheap routers, randomly hanging and requiring a physical plug / unplug when the room gets hot, or whatever other interferences degrade their performance over time.

Expensive ones are still not 100% reliable, and most of the time will cost more than a well done ethernet installation.


Never had any problems in three different houses. Two different brands (we use AVM Fritz!PowerLine now). I reliably get high bandwidth and low latency. A gave an old set of adapters to my parents in law who live in an older house (from the 1930s) and it works well for them as well.

Of course, as a sibling said, it'll depend a lot on the wiring and/or other connected devices. So I guess it's best to try with a borrowed pair of adapters first.


I've had one brand that did not work at all, but netgear powerline adapters 500mbps or better have been solid for me even in heavily congested outlets.


These are good but if you have any analog audio/video kit nearby (or if you listen to shortwave radio) you'll hear them.

Also, avoid TP-Link adapters as they seem to have some issue coming out of powersave mode that means I have to ping something all day to prevent them from sleeping


Price. $1500 (50 USD) for power-line Ethernet, $300 (10 USD) for a wire. And the lower latent power consumption, and the fact the wire is less likely to be the cause of any problem.

I'm renting the house, and wherever I move next probably won't have this problem.


I suspect the OP lives in a country where house power wiring is a bit shakey.

In the UK I have had very few problems with powerline one failed through over heating and had an issue when we had our solar panels installed as the POS Netgear router didn't implement STP and we had a broadcast storm


You, sir, are a badass. You should sell wifi power cycling sockets. I will be your first customer.


This is how it always ends - wired ethernet where you can and rebooting malfunctioning wireless devices (or all of them if unsure). Why can't we have nice things?..

Good idea about automation, I try it at home.


"After some thought about WiFi repeaters, I decided to buy a long Ethernet wire and run it down the stairs."

Would some of those 'homeplug' plugs that use the mains wiring as a closed circuit low frequency radio signal link be tidier? I used a fairly low speed pair to get Internet from modem/router downstairs to desktop PC upstairs without drilling holes and running cable. Worked ok.

https://en.wikipedia.org/wiki/HomePlug


No, I bouht some recently to experiment: Always about 10% packet loss (yes, i was on the same circuit, packet loss was much worse across circuits)


fair enough. Cable ties on the side of the stairs then - don't want any accidents.


or even use those cable clip things and run the wire along the ceiling/floor, paint the lot the same colour as the wall


Why is power cycling bad for the router?


It isn't. The OS is only mounting the flash writable on configuration changes. Hard rebooting it is expected and designed for.


This is a great illustration of why the naive belief that a microservice architecture will solve all the things is so ill-conceived. When developers fail to properly assess how deeply coupled microservices are to their dependencies, the result is cascading failure scenarios that take down the whole ecosystem.

Perhaps we should aim for 'services' architecture that are just right. When two concerns are deeply coupled/dependent on one another, the ecosystem will likely be more robust if these are left together in a single service. In addition, this adheres to good old fashioned software design principles of striving for good coupling/cohesion relationships.


> <insert buzzword> will solve all the things

This is the failure irrespective of what <insert buzzword> is.

However, in my opinion, microservices are about decoupling rather than reliability.

In addition, proper use of microservices means that people producing for and consuming from a microservice now MUST plan for how to detect when it is down and what to do when that microservice is offline.


After 20 years of buyin (15+ routers) and searching for a wifi router that "just works"TM in large house scenario I finally found the ASUS AC5300.

https://www.amazon.com/gp/product/B0167HG1V6/

It has 3 radios on board 2x5ghz and 1x2.4ghz.

It has a mode that allows you to use a single ssid across all 3 radios. It uses QOS to dynamically switch each devices to the best radio for at any moment.

I purchased the same device for a small retail business and it works amazingly well in that setting too.

Highly recommended.


I've really been enjoying my Ubiquiti setup that I switched to about 5 months ago. The internet has still gone down but that is due to my ISP and not the hardware.


+1 for Ubiquiti Unifi. Got 2 AP's and a Router and it has been great with no issues so far (3 months). Upgraded as my previous combo router (with OpenWRT Gargoyle) would silently stop allowing wireless devices from connecting to the 2.4ghz at seemingly random intervals.


How do you feel about the security of the products? 20 year old PHP versions and the company itself was scammed out of tens of millions of dollars. I see good reviews from bloggers on the hardware, but the company doesn't seem to have made security a priority.

One recent example, there are plenty more out there: https://www.theregister.co.uk/2017/03/16/ubiquiti_networking...


That’s worrying indeed. But is the track record of Asus/Linksys/Buffalo/etc better? For decent security I guess the best option is to run pfSense or similar, but that seems to require more expensive hardware.


Ubiquiti can get expensive for a home user, but yeah. It's rock solid gear, truthfully advertised and still a bargain at that price point.


Not expensive, a single UAP-AC-PRO is maybe $125, add a mikrotik hEx RB750GL and you're golden.

The 802.11N Unifi gear is <$200 for a three-pack and works of MikroTik passive PoE like the RB260, 5-port gigabit PoE with an SFP cage.

MikroTik and Unifi is an unbeatable performance/price combo for individuals, large homes and business scaling up to medium sized and multi-site deployments.

With those prices and features you can affordably dog-food the setup and support your friends and family.


This is more or less the exact setup I'm using (Ubiquiti AP and RB750). I've only had it for a few months but neither have required rebooting once they were set up and the performance is good enough to make my 150 Mbps connection the bottleneck.

I also enjoy the level of control that comes with having separate devices for cable modem / router / wifi AP, for example being able to ssh into the router to configure things like port forwarding.


I went with a full Ubiquiti setup (USG + CloudKey + UAP-AC-PROs) because yeah. Spent more than I should have, but the USG is actually a great dual-wan router. Already had a PoE switch for the APs though.


In 15 years my family has gone through maybe 4 routers total. The first was the original 54G linksys router, that didn't even have wifi, eventually we upgraded to the WRT54G, and had that for at least 8 years, finally it couldn't handle all the devices so we upgraded to an N, 5GHZ, we only had to replace that one because of a faulty surge protector and a power surge. Since then we've had no issues in a fairly large 6 bedroom 3 story house.


Since then we've had no issues in a fairly large 6 bedroom 3 story house.

It depends very much on the construction of your house and interference of other nearby APs. We have an access point with a six-element beamforming antenna array (2.4GHz and 5GHz, Airport Extreme). WiFi in a room next to the AP is still reasonably ok. But once there are two walls between the AP and a device, the signal is basically gone.

We now use Powerline Ethernet and get excellent transfer rates around the house. (Of course, performance depends on the wiring, etc.)


Over $300CAD for something that "just worked" a decade ago. I had a WRT54G that was rock solid back in the day that cost me $80CAD to buy, and now I have to pay 4X as much to find something "reliable"?


No, you can spend $50US on an Edgerouter-X and then another $80US for a ubiquity AP and have something that "just works" amazingly well. Or a little less and get an TP-Link EAP series AP[0].

[0] I went this direction and it's solid.


Only tangentially related -- I swear, nothing makes me feel more technically incompetent than debugging WiFi issues. I do moderately low level systems programming all day long, but I can't get the damn internet to reach from my living room to my desktop computer?


I mean, the fact that WiFi works at all is amazing. We're encoding information--lots of it, too--and sending it through light forms of energy ripples through the air, which we can then decode.

All of this happens at a sub-millisecond rate. Technology is amazing, and we can sometimes forget that [0]. I wouldn't treat yourself harshly because you don't fully understand it.

[0]:https://youtu.be/zbCoe3vIskA?t=40s


That was a really wholesome comment :) As someone who feels a lot like the GP, thank you and you're absolutely right.


I run a Microtik Routerboard and a few Ubiquiti Unifi AP's. Never had a peep out of it with over a years uptime now.

The problem seems to be shitty consumer grade hardware (isn't it always), I'd advise upgrading to entry-level business grade gear, it's much more reliable.


+1 for the MikroTik routerboard. My 2011UiAS-2HnD has been running great for 2 years.

Caveat: the configuration UI complex! It's easy to set up a basic configuration. More complex features (vpn, port forwarding, custom firewall) are arcane, in the same way configuring a Cisco router is arcane. But those complex features are available!


Yep, the quick setup will handle a standard residential configuration for you, but if you want failover or load balancing things get more complicated.


>The problem seems to be shitty consumer grade hardware

Partially....

Yes, consumer grade hardware sucks, but so do consumers. When you see a wifi router in a corner, partially covered in junk (or blocked by household stuff), and it's power brick is sandwiched between 5 devices and is running about 150 degrees, it's not really the hardwares fault.

People that tend to install pro-sumer/commercial equipment tend to plug things into UPS's with proper ventilation and center of the room mount their AP, leading to a far reduced number of incidents.


Mikrotik is also as cheap as it gets.


Yeah, but cheap in the same way as a refurbished ThinkPad, not cheap as in poorly quality.


I don't know who this analysis is aimed at but I would advise caution in trying to apply it.

My main criticisms of the article are that it: (1) ignores modern wi-fi mesh technology; (2) oversimplifies "solutions" to the point of false equivalencies; (3) ignores performance and convenience concerns; (4) uses vague language ("it works"); and (5) treats "wi-fi" as a black box that operates in a vacuum and is not amenable to tuning (channels, power levels, freq's, etc.).

Ironically, the author's "buddy wi-fi" proposal embodies a subset of the capabilities of a current consumer mesh setup such as the Amplifi product that I use in my 3-story home.


> I don't know who this analysis is aimed at...

I can answer that - this is a slightly edited version of something Avery wrote internally when we were both working on wifi routers for Google Fiber. Imagine that you wanted to explain to someone why it's hard to build a good wifi extender/repeater (and therefore why you need additional headcount to do so).


What's true about modern meshes that obviates the conditional probability of success? This'll be news to me!


Modern meshes still often have a choke point. Kill enough nodes at the right point in the mesh and the reliability degrades quickly as the backhaul links get oversubscribed. At least that's what I think OP meant :)


Intriguingly, I think my Google OnHub devices use spanning tree to find Internet across the mesh. I actually wired up both rather than use mesh networks on their own, though, and a bug in my Cisco wired switch's use of spanning tree was what caused problems -- despite having the cables connected, and ethernet running just fine between them, the spanning tree figured transmitting over wireless from one OnHub to the other would be faster than the ethernet switch between them. (The fix was to disable broken, manual spanning tree settings on the Cisco switch.)

This indicates to me that if you had a dozen Google Wi-Fi devices and a few of them had ethernet connections, the rest would quickly find the shortest path from your device to the AP you're connected to the nearest mesh device with the fastest ethernet to the outside world. I'm not sure how the hops are weighted though, presumably reliability and signal strength plays a role.


> Distributed systems are more reliable when you can get a service from one node OR another.

I'm confused.. why did it take the author years to come up with this? Why is this a revelation?


> 90% of customers

I'm probably being pedantic here, but shouldn't this be 90% of devices? If I have three wifi devices at home, but then I go out and buy a fourth one -- and I find out it can't reliably connect. I've just fallen into the 10% zone. So I order a new router - I get it set up and now my new device works. Yayy!

But now one of my older 3 devices has stopped connecting. I'm still in the 10% failure zone, even after spending a hundred bucks on a replacement for a router that was "mostly" working. So I keep both routers, assigning different SSIDs so the wireless devices will only find the routers they like. Have I now decreased my overall reliability because I'm now running in the "And" case with it's 90x90 multiplication, not the "Or" case? Most likely.


Interesting, I just moved the ISP router back into the living room instead of my room, and used a tiny Range Extender. The bridging makes internet very different, latency is random, throughput will cap and then drop from time to time.. I suppose a network engineer would probably know how to make router and RE talk together better.


>Replacing your router:

>

> Vendor A: 10% broken

> Vendor B: 10% broken

> P(both A and B broken):

> 10% x 10% = 1%

>

>Replacing your router (or firmware) almost always fixes your problem.

The conclusion is false :

if router A is broken, router B still have 10% chance to be broken, the two events being independant.

P(A broken | B broken) = 10%

To get the 1% effect, advice could be :

Always buy 2 routers instead of 1


What exactly are you saying is wrong?

If you have to replace the router, there's a 10% chance that new router is broken. But you only replace when the first router is broken, so it's 10% of 10%.

Read it as "a strategy of replacing when needed" rather than "replacing in all cases for the hell of it".


The strategy "Buy 2 routers, and if the first one fails, then use the 2nd one" is ok, and gives you the 1% result.

My (little) problem is the sentence "Replacing your router (or firmware) almost always fixes your problem.", because if the first router is broken, replacing it will only fix your problem in 10% of the cases, which is not "almost always".


You don't actually have to buy a second router upfront, so that's not a good way to word it either.

I'm struggling to find a great way to put it. Maybe "a one-replacement backup plan gives you a 99% chance of success"? Close but not very elegant.

"Replacing your router (or firmware) fixes the problem except for 1% of all router buyers"?


This is a bit like the gameshow where you select from 3 doors, and then one door is removed and you have the option to change.


This assumes the client can cleanly switch between the two routers. That doesn't happen.


Author forgot to add that clients also work only 90% of time (I'm looking at you, expensive Samsung and Apple phones). So in case of Router plus AP you get 0.90.90.9 = 72% reliability. Basically wifi is a mess.


with my wireless CCNA hat on I am not sure describing an extender as a router exactly makes me that confident about the article.

"Adding an additional router almost always makes things worse. " Not if you know what your doing :-) if it said adding an extender I would have agreed.


What's the best COTS WiFi module for as-generic-as-possible WiFi sniffing?


Anything ath9k PCIe would be my guess. Driver is open-source, little to no closed firmware and it's battle tested and good Linux support. No 802.11ac through but for sniffing it shouldn't matter.


Edge cases are king in networking, at least now that humans are so "connected".

Sometimes I'm playing a multiplayer online game and the connection lags for a second. My network then switches over, which takes up at least more "real time" than the actual lag (perhaps re-initialize sockets or arbitrary NAT operations or something).

Here I want it to opt for the 1 sec dropout, because it will only take a second, instead of often needing to reload client on a network switch. The router's logic is "not wrong" though.

Another problem is when 2 connections are close in signal strength. Ever other minute my network switches, coming across as pseudo-lag, because it's noticeable.

Many "modern" webapps are designed to compensate for this (also for general offline usage). A "modern" web app does not actually need persistent stable connection to function. It either caches or just needs initial data (variables) and does all the calculating logic client-side.

I like this, because it's more on similar grounds with how humans have/are working/communicating together in real life.

This has more to do with conceptual architecture, and not tech though. Many off these things can be configured right as it stands, but routers default setting is: "stupid". This offcourse has it's reasons.

Wifi also often gets confused if other wifi routers are nearby, or more relevant, if say 10 devices operate concurrently on the same local wifi. This is handicapped from the get go, because it has to filter the right packages out off the air. A wired connection is basically absolute about this. Like the article has stated, LTE seems more stable, because you have 100's off "routers" ur phone can choose from. Consumers don't want to buy 4 routers more for around the house to ensure optimal redundancy and stability.

Best would be to not even hook nodes directly to a main consumer router, but a switch. If ur main acces-point fails on a software level ( or hardware for that matter), everything down the hierarchy is irrelevant, even though ur "landline" is working just fine.

I also wish routers were less static from a consumers perspective. Ie. if i'm doing stuff on the net, I want my router to send me a msg saying, "hey for the past 20 minutes, you seem to have lag spikes, shall I switch to node x for you? prompt yes/no "

There's not much done to make routers user friendly (isp has it's own personal-gain-y reasons for this). These things should be more integrated to the user. Again there are good reasons like security to not have a hard bound to your "main machine", just saying that it irks me.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: