The Wi-Fi only works when it's raining
predr.ag
predr.ag
http://www.ibiblio.org/harris/500milemail.html
Or the Magic/More Magic switch
http://www.catb.org/jargon/html/magic-story.html
It's fun when physical reality meets the abstract models that we have built in our heads of these machines.
Some of my favorite video documentaries are on how it was theorized and then slowly developed over years and decades until they finally got to spark-gap transmitters.
https://en.wikipedia.org/wiki/Timeline_of_radio
But just imagine listening to spark-gap morse code radio broadcasts for years as amateur and then suddenly someone does a broadcast test of actual voice (violin!) That must have been incredible to hear wirelessly.
24 December 1906 Reginald Fessenden, that was the leap that eventually gave us wifi
> If the problem had had to do with the geography of the human recipient and not his mail server, I think I would have broken down in tears.
https://bugs.launchpad.net/ubuntu/+source/cupsys/+bug/255161...
Reason: the server had IPv6 turned on, and it steadily accumulated privacy IPv6 addresses. These addresses were all sent in a packet describing the supported media endpoints, using UDP.
And yep, eventually it overflowed the MTU and the phones couldn't handle the fragment reassembly.
That mad IPv6 address thing must have stuffed up more than just a VoIP negotiation packet. DNS switches from UDP to TCP when responses get too large.
SIP is special because the signalling and media protocols are separate. So when a call is being established, the parties exchange their media endpoint locations. This necessarily means that the server has to list its IPs (or DNS names) so that the client can choose the best one. And as a quirk of SIP, it sends the entire set for each of its supported codecs.
Yes, I know, just like ftp 8) I do hope that whomever invented putting the control channel in a separate stream from the data is mildly discomforted. Mind you, all that stuff was invented a very long time ago, when trousers were a major trip hazard.
My go to fix is "symmetric RTP", which seems to have become a default over the last decade or two.
I did tech support via phone for a popular consumer computer brand. One particular call, a woman reported that her computer was restarting every time someone in the house flushed the toilet.
Long story short, her home was in the back-back woods with the home powered by a generator. In addition to powering the computer, the generator was also the source of power for a water pump which would kick on to refill the toilet bowl whenever it emptied. And wouldn't you know that that water pump had a beefy coil around its motor and would brownout the entire house every time it started?
It turned out that some joker had rearranged the numbers keys on the keyboard, so they were ordered "0123456789" instead of "1234567890". And the user's password had a digit in it. When the user was sitting down comfortably in front of the keyboard, they looked at the screen while they touch-typed their password, and were able to log in. But when they were standing in front of the computer, they looked at the keyboard and pressed the numbers they saw, which were wrong!
I had a shortcut on my desktop with the weather for that town ready when they would inevitably call and blame our unrelated equipment for some problem.
Every few days, always at roughly the same time, all incoming dial up traffic would drop. A minute later, the customers could reconnect.
It took a while before we realized that one of the huge passenger ferries that docked a short distance upstream was the cause. When it arrived and departed, its chimneys and possibly bridge and highest deck blocked LOS across the river.
A famous blog post investigating some of the towers as an outsider, at [1], will be of interest to you.
If you want to guess where they are, get a globe, find the datacentres where electronic exchanges operate (it's not a secret: Chicago, New Jersey, London, Tokyo, Frankfurt, Zurich...) and draw the straightest possible lines between pairs of them. Microwaves don't cross the ocean.
[0] https://www.mckay-brothers.com/
[1] https://sniperinmahwah.wordpress.com/2014/09/25/hft-in-my-ba...
There now exists hollow-core fiber, where the light travels down an air gap in the middle, which is theoretically competitive with microwaves/lasers/etc. How much this is being used is a secret, but microwave transmission definitely hasn't gone away.
[0] magic-story
Eventually I realized that the sensor is an optical beam, and the receiver happened to be in direct sunlight coming in through a window! So it was continuously receiving infrared and would never report the beam being blocked by a pinball. Sure enough, it started working again once the sun angle changed by a few more degrees.
> "Anyway, I asked one of the geostatisticians to look into it--"
> "Geostatisticians..."
> "--yes, and she's produced a map showing the radius within which we can send email to be slightly more than 500 miles. There are a number of destinations within that radius that we can't reach, either, or reach sporadically, but we can never email farther than this radius."
I adore when experts use their expertise to analyze real-world things like this and provide ridiculously thorough explanations :-D
https://longnow.org/essays/richard-feynman-connection-machin...
It's a few paragraphs, maybe too much to quote, but the bulk of it starts with:
> By the end of that summer of 1983, Richard had completed his analysis of the behavior of the router, and much to our surprise and amusement, he presented his answer in the form of a set of partial differential equations. To a physicist this may seem natural, but to a computer designer, treating a set of boolean circuits as a continuous, differentiable system is a bit strange. [...] Our discrete analysis said we needed seven buffers per chip; Feynman's equations suggested that we only needed five. We decided to play it safe and ignore Feynman.
Guess who was right.
The whole essay is worth reading, if you haven't yet.
https://en.m.wikipedia.org/wiki/Thinking_Machines_Corporatio...
One thought I had while reading this was what areas of technologies are still open to amateurs.
This is a very common thing in older automotive electronics, for example.
I think the one that stuck out to me was the Soviet mainframe computer that would get weird bit flips almost every day, always at the exact same time. Somebody compared what was different about the days it didn't get bit flips on, it turns out those were the days on which a particular train didn't run, the computer was very close to a railway station. What train was it, you ask? The one transporting the (definitely perfectly safe to eat, definitely not filled to the brim with nuclear radiation) cow meat from Chernobyl. The radiation was intense enough to cause bit flips, I'm sure the quality of soviet components didn't help here either.
https://beza1e1.tuxen.de/lore/index.html
Also posted on HN awhile back:
https://news.ycombinator.com/item?id=23005140
Edit: yep, here are your Crash Cows: https://beza1e1.tuxen.de/lore/crash_cows.html
Discussed many times here in HN:
1. https://news.ycombinator.com/item?id=37576633
Every night, for about 10 minutes, the connections from our HQ to a relay tower became flaky. At the time we were using two Mikrotik 5GHz cards and some large antennas.
You could sit in front your computer and wait, a few minutes after the sunset, for the monitoring alerts start arriving. After a week trying everything, including changing hardware (to the same specs), I was very disappointed with the thing and got out to smoke around the sunset.
Then some huge lamps we had around the building switched on, based on a light sensor. Immediately I received the SMS alerts on my phone. I ran into the building, turned off the external lights and bingo: 0% packet loss.
It turns out that the building management had changed all of external lamps the week before, with new sodium-vapor bulbs. And for some reason, on the first 5 to 10 minutes with these lights on, it caused very high interference on the 5GHz band.
Changed the lamps, problem solved.
The ballast and the bulb itself are quite noisy in RF and then they are heating up they even more noisier.
Every week day + Saturday, from 7-3 the link would keep cutting out intermittently. Then work fine and the rest of the day and on Sunday… a crane, building a new residential building would operate during those hours right in the middle of the microwave path. Many weeks of theories and time wasted until someone had a chance to visit. :)
Plastic drones with plastic propellers are still visible on radar because the tiny propellers spin super fast, so they light up like a Christmas tree on Doppler radar because the approaching vs receding velocities of the blades are so different.
Is it that radar can't ping / receive at a high enough frequency to distinguish the difference between "this fraction of a ms the blade was at that location so we don't care about the radar hitting something, but the next fraction of a ms the blade had moved and we still got a ping from just behind it so there's something there"? Or some other problem with the idea?
Reflections from targets also need to pass the turbine(s), reducing the return even more.
Beamwidths are significant, depending on the antenna configuration. You can have beamwidths of 0.5 degrees and more. That helps detection, but reduces target discrimination. It helps get the energy past the turbines, but you tend to have "wound down" the power output to allow for that. So it doesn't really help.[1]
You know where the turbines are ... knowing the exact positions of the blades won't help at the frequencies being used.
In short, it's complicated. Radar pulses are like HUGE lumps of energy flying through space, and delicate things like turbine blades chop them up and defect them around, preventing them from getting to, and then from, the targets.
[0] Marine radars, X-Band and S-Band. There are other ranges and bands.
[1] Yes, this is all extremely simplified and inaccurate, but I'm trying to give a sense of what's going on.
There are trade-offs between how often you can ping versus how far you want to see versus how much energy you can send out versus how big the "lumps" are, etc. The sums/calculations are pretty simple, but not obvious until you've seen them, and then they are.
But if you want to see something at 32NM ~ 60km, you have to send out a lot of energy, so the "lumps" need to be pretty big, especially as the returns drop off as a fourth power with distance.
E.g. are the US military saying "yep those are the issues we face too" or "haha our tech has more than enough energy to get around all these problems"?
I wouldn't care to speculate further, but you might want to read about phased array antennas, and FMCW radar. There are some very deep rabbit holes here, and I certainly would not be your best guide.
For me it reminds me most debugging I see at work. People coming up with theories and doing some magic incantations on the interface.
Instead of reading the log files or reading error description which makes usually error and fix obvious in 10 seconds.
We don't typically have log files for hardware, but I'm always surprised when otherwise extremely intelligent people first try to debug by applying "fixes" that shouldn't have any causal effect on any weird observations we've gotten. I have no problem with people coming up with theories because each modification takes time, but each theory should ideally explain the data...
o/~ Wi-Fi's only working when it's rainin'
Players only stutter when they're buff'rin'
Websites, they will page load oh so slooooww
When the rain falls down, you can downloadHindsight is 20/20 but I correctly guessed the ending as soon as that information was added.
After a couple decades of debugging various internet issues the first thing I now do is check the 'source' works (i.e. plug a laptop into the modem directly, but with a different cable). If that works I go down 'the line' until something does not work. That usually finds the culprit quite quickly (and also stops me from messing with my router config when it's an ISP issue).
In OPs scenario, the moment you realise that the office internet is working fine and it's only the home internet that is having issues, the connection between the two would have been the obvious place to look next.
That being said, it's still a fun story, and still quite 'unexpected' that rain could be the determinating factor on whether you'll have working internet or not.
At first (without the full context) I thought it was because rain blocked the external signal interference that was making the AP channel look busy.
One particularly exhausting day, I trudged back from the train to the parking lot, eager to get home and unwind. As I approached my car, I noticed something peculiar—all the windows were missing. Panic gripped me, and I initially thought someone had vandalized my beloved vehicle. However, as I walked around the car, I couldn't find a single shard of glass on the ground. Upon closer inspection, I realized that the windows had simply been rolled down. Relief washed over me as I rolled them back up and drove home, putting the strange experience out of my mind.
Weeks passed, and the incident faded from my memory. Then, on a lazy Saturday morning, I sat on my back porch, sipping a hot cup of coffee and enjoying the tranquility of the day. Suddenly, the sky darkened, and a light rain began to fall. As the raindrops pattered against the roof, I heard an unexpected sound—the distinct whirring of car windows rolling down.
Perplexed, I set my coffee aside and hurried to the front of the house. To my astonishment, I found my Volkswagen's windows had mysteriously lowered themselves, allowing the rain to pour into the car's interior. It dawned on me that the windows' odd behavior must have been caused by a short circuit in the electrical system.
From that day on, I knew my 1998 Volkswagen Wolfsburg Edition was more than just a cool, bright red car—it had a quirky personality of its own, keeping me on my toes with its unexpected window antics.
The first time it happened was on a music festival after hauling a lot of camping gear from the car. I locked it using the remote key fob, put the keys into my pocket and hauled the last bunch of stuff to our camp. An hour or so later someone told me that my car had completely open windows, asking whether that was intentional. Of course it wasn't.
The next time it happened was at home, after shopping for groceries. I locked the doors, carried the box with the groceries into my flat, and when I finished unpacking them I looked out of the window and saw my car in the parking lot - with fully lowered windows. I thought it was a glitch in the firmware or whatever.
A few days later the same thing happened again - I shopped groceries, carried them in, looked out of the window - car had lowered the windows entirely by itself. The same glitch twice within a few days? In almost the same situation? How big are the chances for that?
Then it suddenly dawned on me.
I have quite a lot of stuff in my pockets. Including the car key with the remote buttons. Whenever carrying heavy stuff, boxes and such, there is quite a good chance of me accidentally pressing the "unlock" button not shortly, but for a few seconds. So I took my key fob, stood in front of the car, held down the button...and after five seconds of waiting, all of the windows lowered for just a little bit, and after waiting a few additional seconds they lowered completely.
Since then I know about an interesting feature of my car: it can remotely lower the windows for ventilation in summer.
Can log in while sitting down, can't log in when standing up.
I need to find the reference ...
Edit: OK, here's one version:
https://www.reddit.com/r/talesfromtechsupport/comments/3v52p...
https://news.ycombinator.com/item?id=21978004
[Edit: I see this one has also been mentioned a few times already in the thread]
In the end there were two print screen buttons, only one of them functional, and one of them more obvious when standing (or sitting).
These kind of stories are classic debugging parables that teach you to step back and consider what you may be assuming incorrectly when something absolutely doesn't make sense or seems impossible.
The house end is inside a UK standard tiled roof - dense 3/4", allow for slat, so 1"+ thick and dense material.
The other end is 20m away (LoS) and external mounting was forbidden. The garage block has foil lined Kingspan style insulation. I managed to mount that end near enough to a skylight window to work OK. I then daisy-chained an access point off it.
All was fine until the sky light was replaced with a metalicised one. The signal just about worked until it rained which was enough to nobble it.
When it got annoying enough, me and said family member plotted and I rocked up when someone was absent for the weekend. I moved the garage station to the outside. It now looks like a bird box. I put up a real bird box at the other end too. The fake box would get baked in the sun but the real one is always shaded.
...
(Wife Acceptance Factor - far more important than Web App Firewall)
Also see: https://www.townplanning.info/permitted-development/househol...
Just what I found doing a quick search.
It failed later and me and my brother may have conspired a little bit ...
Dealing with your nearest and dearest can be quite tricky. I think we got this right ... this time!
It took me a while to realise the difference was that the homelab was physically connected and the laptop was using Wifi.
The laptop wifi was connected to the AP at ~1.2 Gbit and a different machine had the same issue. I decided to see what the internal network speed was and found that sending/receiving files to the homelab from a wifi device was also maxing out at ~90mbit.
This then steered me towards looking at the connection between the AP and the router, and I realised that the Wifi AP was connected at 100Mbit to the router instead of 1Gbit. Turned out the cheap CAT7 cable that I randomly used to connect Wifi to the router because it looked nicer than the existing cable was not actually a real CAT7 cable and only provided 100Mbit. Changing the cable fixed the issue! Out of paranoia I decided to replace all of my ethernet cables with decent quality ones.
I don't even remember where that 'fake' cable came from; probably from some random Aliexpress appliance that I bought at some point. I've had similar issues with USB cables that I've amassed, where I forget where they came from and only realise later that they barely fulfil their purpose.
Homelab is physically connected to the router whereas the laptop is connected via Wifi. It was the cable from the Wifi AP to the router that was dodgy which caused the issue.
I noticed because the laptop would never reach 'true' 100Mbit download speeds whereas the homelab did.
What is worse is that the hardware tries hard to make it work even with noncompliant cable resulting in things like random flashes of black, or multiple random reconnections after plugging in the laptop.
I guess the same question stands for USB cables. I remember looking into that a while ago but did not find anything conclusive.
"The office and our apartment were a few blocks away from each other..."
and figured it had to be a line of sight transmission.
I encountered this in summer of 1993 when the company I worked at installed infrared (I think) transmission across our two offices, separated by 250m. When the summer sun swept behind the transmitter in the northwest-ish, the wifi went out for about an hour each evening.
> Interestingly, objects outside the straight line between antennas can still cause interference! For best signal quality, the Fresnel zone between the antennas should be clear of obstructions. But perfection isn't achievable in practice, so RF equipment like Wi-Fi uses techniques like error-correcting codes so that it can still work without a perfectly clear Fresnel zone.
I wonder if other waves like pressure/audio waves also have a similar effect.
[1] - https://en.wikipedia.org/wiki/Fresnel_zone
(Side note, is this story old? 802.11n isn't particularly new enough to upgrade to.)
At the far end you’ll hear (although in reality, your brain will almost certainly cover this up for you) distortion caused by the sound wave defracting off the obstacle and interfering with the primary wavefront. Hence the reason why people put so much effort into design concert halls, and adding sound dampening treatments to recording studios. Obstacles will distort sound, but energy absorbing obstacles will distort less.
FTA:
> At the time, I was still a college student — this was over 10 years ago.
Terrestrial TV (some of which used bands that overlap FM radio) uses horizontal polarization.
A widened beam of collimated light (i.e. parallel beams) is sent through e.g. a slide with some image printed on it. Using a lens placed one focal length away, it is focused down to a point (one focal length from the lens). One more focal length from that point, the beam will have reached its original width again, and another lens makes it parallel again, projecting it onto a screen placed one focal length from the second lens:
| () . () |
image lens point lens screen
(I'm the author of the post btw)
I've lived in the same place for 25 years, so I've seen the invention of wifi and then checking every few months for other users on wifi analyzer, I've seen it grown and grown.
Well in that 25 years they've built so many surrounding apartment complexes that the 2.4ghz saturation is absolutely insane. I cannot believe how many networks show up on the analyzer in 2024, has to be well over 100.
But when it rains, it cuts off dozens of those other apartments, and I get better signal inside my own apartment.
But the other one was setting up WiFi between buildings, and tended to be more of a problem in academia because the yearly cycles make it a bit more likely. If you set it up in the fall, and everything works all winter until spring comes, when the water in the deciduous tree leaves attenuates the signal. The nasty part of this one is not the failure mode but the timing. Everyone has been happily using and depending on their sweet sweet bandwidth for six months and poof, it’s just gone one fine April morning.
Also why not lay a cable.
"Just" move it higher vs replace ~10yr old (at the time) equipment with newer, faster equipment that doesn't have the problem? Easy answer if you ask me, and I'd make the same choice again with ~10yrs of retrospect -- the same 802.11n antennas are still there today!
I don’t think so. I definitely know tech people who get a particular idea in their head and will debug it to hell and back before taking a step back and realizing the obvious thing they missed. I’ve definitely done it before myself.
> Also why not lay a cable.
It sounds like they were trying to run a network between two properties that weren’t adjacent. They may not have had permission from the neighbor in the middle to lay cable on their property, or it might’ve required laying a cable across a street.
Past ~300ft/100m, you need a repeater even for Ethernet. We would have needed at least one repeater somewhere along the line, which adds even more cost and complexity on top of needing to get permits from the city and approvals from all the neighbors in between. Anyone that says "just go get a permit from the city" has never tried doing it.
Edit: it probably did as the story is 10 years old.
Other than that I'd agree about your solution being optimal back then, and now. Btw how did you check the power brick, peak to peak voltage measurements? Bad capacitors is likely the single most common failure.
According to the stories the two bridge endpoints were in different buildings a few blocks apart. You can't just lay a cable in the middle of a public street.
Also, if it was roughly 10 years ago then upgrading to N wireless was a good solution anyway. Not only did it solve the problem but it would've given then quicker speeds.
Chances of getting proof that this happened are zero
I've had trouble with tree growth in other contexts. A tree once slowly grew tall enough to break the neutral wire on the drop from the power pole to the house. This put overvoltages on some 110V circuits. Computers were fine. Washing machine emitted a burning smell. More recently, tree growth broke a fiber line coming into my house. AT&T lineman came out and restrung fiber for three poles (I'm a ways back from the main road). He saw me running a desktop computer, slowly, tethered to a phone, and once fiber was reconnected, said "Now you're back in 2023".
(Now to get rid of the dead cable. I have dead DirectTV coax, dead cable TV coax from whoever was before Comcast, and dead Pacific Bell copper, all abandoned in place and some of it sagging.)
20ish years ago I hung out in an IRC channel in which, during autumn/winter months, one person would frequently get disconnected and when he came back complained about foggy weather.
He had a laser line or sight connection. It could handle rain (with some degradation), but thick fog killed it.
They were rigging a servomechanism to automatically aim the antenna and wanted to write the control software in Chicken Scheme (for whatever reason, never questioned because Chicken is fun).
This made me smile. My brain autocompleted the fix to something like "help the neighbors trim their tree", but of course the fix is new hardware.
Also, I hate operational (ongoing) solutions to problems. Pruning it would have been exactly that kind of solution -- we'd have had to prune it regularly or else it would have kept being a problem every so often.
The hardware fix was easier: our equipment was already a bit old and slow, the upgrade fixed the rain problem while also making it faster, and it's not something we've had to tweak since. I've long since moved out, but my parents still use that same 802.11n bridge today!
Anyway, for the situation in this link, they actually have a WiFi bridge from their house to their office which has the connection to an ISP, so it is absolutely accurate to say the WiFi was down in this case.
I have some fancy Asus Mesh wifi routers at home. I sit next to the cable modem and one mesh endpoint. My wife sits upstairs. there's an upstairs mesh endpoint but I think neither of us are usually connected to it (mostly serves to extend our connection to go to yard). But when my wife gets up from her desk and walks through our hallway (closer to the non often used mesh endpoint) our internet drops for a bit. My only guess is that the endpoints get mad at meat being in between their back haul? Anyone deal with this and figure out the solution?
Restore to the default settings, make sure you have updated the firmware, and cross your fingers.
I'm in an older home with questionable wiring which I'm sure is also a factor.
I'd replace the chair but it's so dang comfy.
I hit this in a hotel, back when I was doing steampunk conventions. Antique Teletype machines put into brass and glass cases, getting text messages over the Internet. (Early versions of this used Google Voice to read SMS; later versions used Twilio.) The hotel lobby had WiFi, but the function room we were in did not. I'd tested in advance, and was able to get a good WiFi connection with the room empty. But once it filled up with people, we couldn't get through. Had to run out to Fry's and buy a WiFi booster.
End result: your taxi driver's data plan will work whatever the weather :)
B&H comes with its own bag of problems too.
The Russo-Ukrainian war reignited a desire in the EU to actually enlarge towards the Balkans and Eastern Europe. But the countries that haven't joined aren't in great shape (the healthier bits of Yugoslavia joined earlier), and it's not clear to me that any of the current batch countries (especially Bosnia) will be able to join before such desires cool again.
I left the company last year, having grown to 700+ employees in pharmaceutical manufacturing, a far-cry from my one-man IT department for 20 employees making shampoo. And while there were many, many weird issues over the years, none was ever so satisfying to resolve.
Turns out it had been so long that the wifi MAC was picking up a DHCP address that was blocked at the firewall; the dock had its own MAC so it got a good address.
Had to sit down and think about it for awhile before I realized it had to be the firewall blocking access somehow.
It turned out my bluetooth headset was using the same band as the wifi but I only figured this out after a few months and a replaced wifi card. I wouldn't wish that experience on my worst enemy.
I had a fun one where every time I would get out of my chair my monitors would turn off, turns out the EM fields from the compression/decompression can actually be enormous in some cases.
Wait, can you elaborate? I have the same and I thought I was hallucinating or tripping a cable somewhere.
Update: reading the reg one, it also had no cusions, it was a standard herman miller so it was a mesh bottom and back.
It would interfere with the Bluetooth signal.
The worst interference problem I've heard of is how USB 3.0 uses 2.4ghz and therefore can cause problems with devices connected with it.
*As an aside, one of my favorite things I get to do at work is when onboarding new Jr. Net Engineers is getting them take our spectrum analyzer into our office kitchen and instructing them to watch the spectrum turn bright red while I make a bag of popcorn.
Anyhow to get to your question, the best answer would be to get some distance between your microwave and set-up you're using with the headset. Otherwise if that isn't possible, then you'll want some headphones that does use 2.4ghz. Replacing the microwave will likely not fix the problem since they all use 2.4ghz band for cooking and at least I've never seen one shielded well enough that it didn't impact others while in use.
https://www.theguardian.com/science/2015/may/05/microwave-ov...
Weird that even a wired connection does not work. Stay curious!
As a practical solution, I used a short bungee cord to keep it from opening far enough to be obvious, and never kept anything of value in the trunk if the car would be unattended.
Just a normal day at the office when suddenly the internet drops out, except for my machine. Everyone else has a network connection, but no internet. Except for me, I can't reach devices on the local network, but I can reach anything outside.
Now, our network is not large or complicated. We have a consumer grade ONT and WiFi router provided by the ISP, and a big unmanaged ethernet switch. There's really nothing to go wrong here.
After some debugging, I notice that I have been assigned an IP address in my ISP's public block. Tracert seemed to show no local network between me and the WAN. It was as if the router had somehow connected my WiFi client directly to the ONT, bypassing the local network. That only barely makes sense, but it was my best guess so I condemned the router.
Next day, new router, same problem. I couldn't explain it. This time though, I didn't have an internet connection, but local network was reachable. Some sanity restored, ar least.
Turns out that our fiber line had been accidentally cut during construction work. Once the ISP fixed that, all was normal.
The question remains, how did I have internet connection through a severed fiber line? It's not likely that the router had a bizarre failure right before the line was cut. I suppose it's possible that Windows had sneakily connected me to some other WiFi network, but then why did I have a weird IP address?
I have no explanations
The admins could connect to their machines, but not to any user machine.
It was winter and we had some heating issues, so I made a script "warmup_the_office.sh" that was meant to launch a "while(true){}" on each core of each PC of the office, but instead launched itself indefinitely on each and all reachable machines, exhausting all pids and preventing distant logging. We had to reboot everything by hand, after some nice warmup.
Did you admit what happened, or was there a "mysterious widespread network failure"?
I also was using our neighboring business's guest WiFi, but again that should have given me a sane local IP.
Every diagnostic I could think of told me I was directly connected to the WAN with no intervening networks. Then again I'm not the best at debugging networks so I could be mistaken on this point. I am 100% certain that the IP address my computer was given was not a legal local network address.
A lot of coincidences and extraordinary edge cases, but it's plausible I guess?
I was not expecting the home Internet all went over a long range WiFi bridge, but knowing that a tree makes far more sense as the problem. Strange how it correlates with rain that way.
Honestly, reading "April 1st!", I was expecting this to be one of April's fools but it turned out to be a true and amusing story.
The author was lucky to solve a technical problem in a non-technical way, unlike me!
A decade ago, I had a weird Internet connection issue. The upload speed suddenly dropped to near zero kb/s while the download was alright. I contacted my ISP, and for weeks, they were unable to figure out what was going wrong. I reached out to my neighbor and offered him to pay his Internet bill in exchange for sharing his Wi-Fi with me until my ISP solves my problem, and he kindly agreed. After about three months, my ISP's technical staff was still unable to fix the issue. I gave up, and guess what I did to get around this?! I just moved away to another distant home.
I called the telecom company many times. They charge per visit in case no problem is found. I always had to explain the situation and ask the technician not to charge me and come when it started raining, a very hard thing to do because we cannot predict forecast and the network went down for 10 min only.
It does not seem a big problem, after all, I could just wait 10 minutes. After this happened multiple times a day every rainy week, making me lose meetings, work, server connections, etc... I had to patiently chase the telecom company and even ask for the personal phone numbers of technicians (to ping them when it was going to rain) until they finally found a solution.
Edit: Found it: https://news.ycombinator.com/item?id=37585548
My PS5 controller refused to connect to my PS5 and I couldn't figure out why. I gave up and after a few days tried again only to realize that the PS5 controller can't connect to the PS5 wirelessly when the wifi was connected but the password was invalid. I still don't know why it was a problem or if it still is a problem but it was a monster to debug. lol
The reason I didn't fix the wifi in the first place was that I didn't have a spare USB C to USB A cable to hardwire my controller and I was playing a singleplayer game. I think it was last of us.
In fact, the causal relationship between rain & wifi is taken as a given by the author:
> If anything, rain makes wireless signal quality worse
It's not too surprising to discover a causal relationship between two things we already know are causally related.
Especially when they reveal that the network is using wifi antennas over a non-insignificant distance in an urban setting. Of course it’s the local wireless point to point bridge! The first thing you’d do is look down the line of sight for interference.
Or that other time, when my mom's phone started crashing all of a sudden. Until we discovered, that it was caused by her new ID card in the folding phone case touching the back of the phone.
I also believe our microwave is adding noise to the same circuit our WiFi router is on. Despite using 5GHz, WiFi is severely degraded whenever the microwave is on.
If the router gets enough energy the "sine wave" of the radio signal starts to flatten out at the top and bottom and becomes a rounded off square wave which we call "clipping". This has the original frequency component, but also a ton of other frequency components that push up into much higher frequency bands like 5GHz.
Fun fact, this is why electric guitars add a high pitch scratchy noise, they're reaching the distortion/clipping threshold of their amplifier.
Took a guy standing there with binoculars to realize what was going on...
Sure enough, this turned out to be RFI from newly installed solar invertors, creeping down the shield of an unused CB radio coax that ran parallel to the phone wiring.
Grr, I hate DSL...
Trees leaves being weighed down by a slight drizzle? What tree does that? None around where I live.
A tree blocking signals that strong as well? Doesn't make sense to me either.
And the same upgrade would often fix it
1:15
At least you get a clue in this case (and the famous 500 miles email), I was having sporadic disconnections with cable internet for the last 2 month and my ISP can’t find anything wrong.
Had to switch back to DSL and pay more for slower speed.
That's just my style of writing, you can check my pre-GPT posts and compare if you'd like.
That parallels my experience but I didn’t realize was commonly understood. I noticed that in the hot summer the Wi-Fi reception in my yard (IE, farther from the access point in the house) is worse. Eventually I decided that summer heat is really proxy for humidity and that it wasn’t unreasonable for high water concentration in the air to provide an obstacle to Wi-Fi signal.
a. Dog was tied to the telephone system's ground post via an iron chain and collar.
b. Dog was receiving 90 volts of signalling current.
c. After several jolts, the dog was urinating on ground and barking.
d. Wet ground now conducted and phone rang.
Which goes to prove that some grounding problems can be passed on.
Granted the equipment could have been cheap, but this sounds questionable. He's asserting that the a few leaves at the top of a tree were blocking it when it wasn't raining? Idk.
It is also true though that rain water has low mineralisation, and therefore low conductivity.
Sure but didn't you say you were using directional antennas?
Rough rule of thumb, a consumer-grade directional antenna (at least at the time, maybe they've improved in the last 10yrs) will give your signal strength a one-digit multiplier (say ~8x), meaning ~7-10dB. But that n^2 means that improvement only takes you 2-3x farther, not 8x.
Here we're talking about ~100x the distance, which would need a 10000x = 40dB improvement in signal strength. AFAIK an antenna like that would cost more than the entire city block where I grew up
7-10dB matches the antennas I personally use, but those antennas are smaller than my phone. You can get a lot more out of a three foot spike or a two foot dish.
(I'm assuming 2.4GHz and hoping they're not lying about the gain.)
This story happened a bit over 10 years ago at this point. At the time of the story, the Wi-Fi bridge was already almost 10 years old -- we'd had the same equipment since I first remember getting internet at home.
That means the antennas at the start of the story were mid-2000s mid-tier consumer level equipment. I don't think a 16-17dB antenna would have been $35 at the time, in either mid-2000s dollars or in today's dollars. I also grew up in a country much poorer than the US, where $35 could feed a family for a week.
At the end of the post, we upgraded to 802.11n antennas (but still tech from 10+ years ago) which solved the problem by being newer, nicer, and having beamforming + MIMO capability which let them be more tolerant of obstacles (effectively, get more dB at the same emitted power level).
As far as what was available at the time, I can't think of a super easy way to check that far back, but I will note that the 17dB stick antennas on Amazon have been available at the same price or cheaper for about 10 years.
But sometimes for direct links you set the modulation, power and data rate fixed. The end result is that changing channel conditions can turn the link from 'working perfectly' to 'not working at all'
I don't recall them being able to change data rates very much (if at all) because the ones at the beginning of the story were 802.11g devices, and 802.11g didn't have channel bonding capability or similar tricks up its sleeve. Newer equipment definitely has more options like this.
Most people living in large metros will never fathom how wifi will simply stop working in the suburbs. It is easy to forget that Internet cables -normally hidden in cities- are completely exposed to elements in suburbs
Lost wifi while at parent's ? Check the roof!
Not sure how you're styling your links, but in a dark mode view, they are effectively illegible.
The post’s disclaimer (and April Cool’s site itself) both imply that the goal is to touch on novel topics and should be genuine content of the author. That said, this story could clearly be apocryphal.
1. u/obi1kenobi told me it was a real thing that happened to him
2. The point of April Cools is that the things aren't jokes. They're real essays written with care, just outside of the author's usual writing topics. Some of the other ones we got this year are about hydroponics, current events in Sumo wrestling, parenting, and decaf coffee.
The org name April Tools was right there!
> One such piece of magic new to 802.11n Wi-Fi is called "beamfoming"
That's not quite true. 802.1ln has MIMO (Multiple-Input Multiple-Output) processing, with "multiple" referring to the number of receiver and transmitter antennas. Beamforming is a special case of MIMO, and MIMO is a generalisation of beamforming.
In a "Line-of-Sight" channel with no reflectors, MIMO converges to a beamforming solution. Capacity is then limited by the ability for the rx/tx array to resolve each antenna in the tx/rz array: the diffraction limit.
In a "rich" channel, with reflectors, MIMO converges to a more complex solution, which takes advantage of the angular separation of the reflectors to resolve the individual rx/tx antennas, even if they are too close to each other to resolve with beamforming. Yes, counterintuitively MIMO capacity goes up as the channel become more complex/rich and less line-of-sight, whereas with just beamforming the capacity would typically go down.
You can sort of think of MIMO as being beamforming where beams are bouncing off widely spaced reflectors, but even that doesn't do it justice. In reality, each "beam" is replaced with complex wavefront ("mode") which is matched to the environment and each mode is orthogonal to the other.
In other words, they were correct then?
I'd say incomplete rather than incorrect, and the complete story is worth knowing as it makes the solution used more interesting.
Beamforming is cool and magical, and MIMO even more so. The post wasn't intended as a primer on wireless technology, just as a fun read for folks to enjoy. I tried to sprinkle in some nerd-snipe-quality technical detail and offer links for folks who might want to dig in, and MIMO is explicitly discussed in both the 802.11n and in the several links on beamforming I provided.
I barely managed to explain beamforming without that sidenote turning into a paragraph of its own. I don't think I could have done MIMO justice in a sidenote.
I felt the need to mention the difference as so many people equate beamforming with MIMO and claim that there is no difference, when in fact that difference, which Foschini discovered in 1996, is responsible for spatial multiplexing and the high WiFi data rates we enjoy. I figured the typical HN reader might be more technical and interested in the difference, or maybe not.
But I do appreciate precise language and the desire to help people learn new things, so thanks for helping make the distinction between MIMO and beamforming clear! I hope at least a few more people know about it now thanks to your comments.