16 ms·

Weirdly broken Wi-Fi access points

178 points by mjn 10y ago

seiferteric 10y ago
Every free wifi I have ever been on has been broken like this in one way or another, crazy ping times, randomly dropped packets or just extremely slow etc. In fact I am writing this right now from an Amtrak train but tethered to my phone since the free wifi is so bad.
- userbinator 10y ago
  If it's truly free (and often even otherwise) there's probably a dozen or more others sharing the same access point as you.
- jsight 10y ago
  I think Amtrak uses cellular connections to the outside internet. Depending upon the part of the country, there is a good chance that the weak point is their link to the cellular network.
  - mindslight 10y ago
    It seemed like Amtrak uses Verizon for backhaul, at least on the Lake Shore Limited. It definitely goes through some spotty coverage areas. Personally I couldn't care less about their wifi though - I appreciate the power outlets much more.
gefh 10y ago
I had exactly the same problem with OSX - all other devices were fine but my macbook would drop packets after 30 seconds or so. Only fix seemed to be a new router. No problems since.
- mjn 10y ago
  Interesting! I looked quite a bit to see if there was anything OSX-specific that anyone else online had documented, but nothing I turned up seemed to pan out. I am reasonably certain that the ultimate culprit here is bad low-end wifi devices that either suffer from bad hardware (too little RAM, etc.) or bad software (some poorly tested customized version of embedded Linux), or both. But I'm really curious why only OSX seems to cause the problem to manifest in several of these cases.
  - hug 10y ago
    Your article doesn't mention it: Have you tried using a statically assigned IP address? (Poor etiquette inside the DHCP range, but maybe if you just snarf the IP you've already leased..) I ask this because OS X's DHCP stack is known to exhibit some strange and unfriendly behaviours: http://cafbit.com/entry/rapid_dhcp_or_how_do http://cafbit.com/entry/rapid_dhcp_or_how_do
    - mjn 10y ago
      I did try that (though you're right that it's not in the article), setting the last DHCP address I'd received as static IP, but it doesn't seem to change anything. Still the same dropouts every ~30 seconds.
      - seiferteric 10y ago
        Maybe try force sending gratuitous ARP's every 10 seconds? Also it might be interesting looking at a packet capture from both android and mac laptop to see what the difference is.
  - cotizo 10y ago
    Hi mjn! I am living in the UK at the moment, and I'm occasionally experiencing the very same issue. My OSX device randomly drops packets (for 30s at a time), while my Android phone has no issues. I am connecting to the internet via a broadband wifi router. I tried rebooting the router, but that does not always resolve the problem. However, when I reboot the Mac, the problem goes away for at least a couple of days.
- the_mitsuhiko 10y ago
  All UPC spplied routers in Austria have that issue. Does not matter whichbwifi is connected. Thr only way I could fix his is to put a second NAT up and have it make a new dhcp server below it. It's a well know problem that neother apple nor tompson are fixing :(
  - xhruso00 10y ago
    UPC customer here as well, good to find I am not alone. Has this been reported to them?
    - the_mitsuhiko 10y ago
      I talked to the Austrian version of it and they seem useless. I don't think they understand there is a problem but as far as I understand it's the same story in other countries as well.
darkengine 10y ago
I used to frequent a coffee shop with a router that would refuse to let my laptop's wifi card connect about half the time. Like the author, my phone could connect but it would simply not respond to any attempts to connect from my laptop, whether booted into Windows or OpenBSD. The only solution was to ask the barista to reset the router, which was all the more frustrating when they refused to do it because everyone else could connect just fine.
- ballooney 10y ago
  That seems like the readonable answer on the part of the barista.
userbinator 10y ago
The details are vague but if I remember correctly, this is due to something OS X does with DHCP that isn't quite standard but apparently helps to make connection resumption faster --- when it works, that is.
- MBCook 10y ago
  I seem to remember this. Was it that OS X started using its old lease while waiting for it to renew under the assumption that it would probably get the same thing and be fine?
  - hug 10y ago
    That's almost exactly the case. Link here: http://cafbit.com/entry/rapid_dhcp_or_how_do http://cafbit.com/entry/rapid_dhcp_or_how_do Previous HN discussion here: https://news.ycombinator.com/item?id=2755461 https://news.ycombinator.com/item?id=2755461
rubberroad 10y ago
Same problems for me, experienced this a lot on my home wifi, using a dual band, modem / wifi router combo. Problems ONLY occurred on my MacBook Pro, no other devices. Purchasing a dedicated modem and using an Apple AirPort Extreme was the only thing that resolved the issue, which annoyed me and made me feel like Apple is further locking me into their ecosystem of devices.
- tw04 10y ago
  MBPs don't support certain channels which is maddeningly frustrating. Trying to find from my notes which channels those are, but when I finally changed from auto to hard-setting to channel 100, all my issues with MBPs on my network went away.
  - xhruso00 10y ago
    Can you please find the list? I think there are just 13 channels (or 11 depends where you are) 2.4Ghz
    - tw04 10y ago
      Still can't find it. I haven't had issues on 2.4ghz, this is on 5ghz. This thread seems to cover about the same thing I discovered: https://www.reddit.com/r/apple/comments/2zo1uo/if_you_have_still_having_wifi_issues_with/ https://www.reddit.com/r/apple/comments/2zo1uo/if_you_have_s...
  - SysArchitect 10y ago
    There are certain channels in the 5Ghz range that require the access point to do checking to make sure they don't actively interfere with radar... See here for a document from Cisco describing the issue: http://www.cisco.com/c/en/us/td/docs/routers/access/3200/software/wireless/3200WirelessConfigGuide/RadioChannelDFS.pdf http://www.cisco.com/c/en/us/td/docs/routers/access/3200/sof... interestingly enough, hard setting the channel to 100 might violate FCC regulations, and DFS should still be used...
    - 10y ago
wtracy 10y ago
My own Linksys router (I think it's a WRV200) occasionally starts to silently drop new connections until I disconnect and reconnect. If my browser has an http/2 connection open, I can continue to browse that particular site, but when I navigate to another site, the browser times out. It seems to only affect one device at a time. Curiously, the behavior became dramatically more frequent (from once every few months to several times a week) when I moved in with family, which meant plugging it into a different modem, and adding a bunch of Windows devices to the network. (When I move back out, I'll probably leave this router behind and get myself something that runs Tomato.)
- userbinator 10y ago
  That sounds like the NAT table has filled up. Incidentally, this is often the cause of problems with "routers" that people experience --- it's not the (IP) routing part that's giving trouble, as that's stateless and involves not much more than packet forwarding. Things like NAT do involve state, since the router has to assign a port mapping and keep track of (TCP) connection lifetimes. If connections aren't closed correctly or the router misses detecting them for whatever reason, the port mappings will stay in the table until they time out (which may take hours or more) or the "router" is rebooted. The problem becomes more frequent the more devices there are on the network which are making connections.
ploxiln 10y ago
Here's a theory based on a bunch of un-substantiated and un-researched facts: Some routers do not allow traffic from IPs which are not active DHCP leases. When DHCP lease expires, they block traffic. But many routers don't enforce this. Some routers give out super short DHCP leases - as short as 30 seconds. But the typical length is 12 or 24 hours. A public or semi-shared wifi router is more likely to use these policies to prevent exhausting the local subnet address pool, which is typically around 254 addresses. Mac OS X doesn't believe that renewing a DHCP lease in 30 seconds is ever really necessary, limits the renewal frequency to once per minute. I'd check the dhcp lease time.
- mjn 10y ago
  An intriguing and plausible theory! In my case though it seems that the lease is 86400 seconds (24 hours), or at least that's what the router is claiming to give out. So I don't think this is it. My guess is that renewing the DHCP lease has some side effect of resetting the session, rather than it being the actual DHCP lease renewal that is important.
- hug 10y ago
  Definitely unsubstantiated: If this is just at an AirBnB, it's probably not going to be a commercial wifi system. On your topic, though, Princeton noticed something similar with regards to iOS and DHCP, although it is several years old now: https://www.net.princeton.edu/apple-ios/ios41-allows-lease-to-expire-keeps-using-IP-address.html https://www.net.princeton.edu/apple-ios/ios41-allows-lease-t... (last tested version was iOS 6.1)
- smellf 10y ago
  Are you serious? A 30 second lease is insane. I've seen DHCP servers that TAKE 60 seconds to give a lease.
  - JoeAltmaier 10y ago
    Was that the server, or the client waiting that long? THe DHCP spec requires the client to broadcast a request, then wait for a while (unspecified) and collect answers, then choose the best answer (metric unspecified). Sometimes when I write DHCP clients I choose the metric as "fastest", then just choose the first answer and don't wait for any more. And it takes on average a few milliseconds to get a lease.
ggggggggggw 10y ago
For those who are curious, there's a bunch of reasons that contribute to why consumer wifi routers sucks ass: 1. Wifi routers are very complicated. You need smart people at all levels of the stack to build a modern wifi router. You need people who know 802.1ac like the back side of their hand, people who know how to set up and deploy linux environments, embedded engineers for debugging OEM driver issues, networking gurus for handling the voodoo in levels 2-4 of the OSI stack, application people for rolling the user interface, cloud people for cloud support. Normally this isn't a big deal, if it wasnt for the next point 2. The profit margins on consumer routers are complete trash. Even if you're one of the big boys with double digit market share, you're going to have a very hard time keeping a decent engineering team staffed and your marketing team staffed at the same time while still breaking even. 3. Consumer router sales are SKU driven. There are dozens of price and performance points you have to hit to meet the demands of the consumer market. You cannot make be profitable with less than 10 actively selling SKUs. Every time you release a new SKU, it's a new opportunity for marketing to try to sell the device to brick and mortar stores that they're trying to expand into. If you aren't releasing 5-6 SKUs each year, you're going to have a very hard time keeping your router on store shelves. 4. Since sales are SKU driven and your engineering team is probably under funded, you have the exciting problem of maintenance releases. If your company has 50 supported SKUs and you find a non-driver issue in one of them, the chances are that it affects 10 other SKUs as well, if not all of your other SKUs. Pushing that maintenance firmware to 50 SKUs could easily take 6 months of combined QA or Firmware development time. As far as your marketing department is concerned, all that time you spend on maintenance releases is time that isn't spent on making new SKUs with exciting new features. tldr: get a business class wifi router
- shmerl 10y ago
  For home usage, high end consumer routers with free firmware work just fine (something like Linksys WRT1900ACS with DD-WRT / OpenWRT).
  - zippergz 10y ago
    Admittedly I haven't tried the newest models, but my experience with Linksys hardware and either ddwrt or tomato was pretty bad. Run for a couple of days and then require a power cycle. Seemed like a hardware issue.
zeta0134 10y ago
I wish he would drop the name of the router he's running into these issues on. I have the same exact issue with my laptop (random disconnects for 30 seconds) only on my home router, and I've been considering replacing the router with something of higher quality. I use an ASUS 750N, which is starting to show its age faster than I expected, but otherwise services the devices in my house just fine. Except for my laptop, which is the only device I actually need to use over wifi on a regular basis.
- givinguflac 10y ago
  I don't think the model is 750N, more likely that's the max speed. Probably you have the 56u or 66u. The Merlin firmware for Asus routers has really improved my experience with the ac-87u. It keeps the stock UI and fixes bugs/adds features. https://asuswrt.lostrealm.ca https://asuswrt.lostrealm.ca
  - zeta0134 10y ago
    You're quite correct, the 750N was from memory. The actual model is an RT-N65R. That firmware looks lovely! I will give that a whirl when I have time to dink around with it, possibly this weekend. Thanks for that!
    - givinguflac 10y ago
      Happy to help out :)
  - mieko 10y ago
    asuswrt-merlin is awesome. I replaced my ISP's shitty combo router with a barebones TP-Link DSL modem and an Asus AC5300 (which physically looks ridiculous) running asuswrt-merlin. It turned one of the more annoying parts of my day into, eh, nothing. It just works flawlessly for months on end.
microcolonel 10y ago
I experience basically the same level of problems on our office's Cisco Meraki gateway/firewall. A couple months ago we had to do a support ticket to get them to fix their spanning-tree implementation because it configured loops in our simple dual-master crossover switch configuration, forcing us to disable one of the masters. Then there was a spurious packet loss problem in one of the default configuration parameters. Now it just randomly stalls TCP connections open until the local node closes them, but allows the remote node to continue receiving packets(!), which is probably the worst thing a TCP system can do aside from simply not connecting. I quite literally had to attempt this post twice before giving up and connecting to a UDP VPN. I have watched my colleagues cancel and refresh webpage loads for the last few months.
- jonatron 10y ago
  I've had all sorts of problems with Meraki APs. They claim to hop around to find the clearest channel, but they all always chose channel 44. Manual channel selection was limited to non DFS channels, otherwise they'd switch back to channel 44. There was no insight into CPU usage, so we were suspicious that some QoS settings made everything grind to a halt, but we couldn't confirm. Switched to high end Ruckus APs and a Juniper router/firewall and it's now working properly.
gpm 10y ago
These aren't even that bad. I've had a router start sending me two DHCP offers, with different IPs. The first offer containing an IP outside the range it was supposed to allocate. After my computer tried to accept the first offer, the router started ignoring me. This behavior survived rebooting the router (and everything else involved), flushing the DHCP table fixed it for some reason.
- voltagex_ 10y ago
  I have a TP-Link Archer D9 on the "latest" firmware that will either: 1) stop giving out leases 2) suffer catastrophic failure in miniupnpd and stop allowing port forwarding This is a $200AUD device and it's utter trash.
deleted 10y ago
[deleted]
colanderman 10y ago
MacBooks have issues with WMM (WiFi QoS). I've seen my connection drop for dozens of seconds at a time when I enable WMM on my router. Selectively disabling it for my Mac (leaving it on for my wife's Lenovo and my HTPC) fixes the issue.
- xhruso00 10y ago
  Thanks for tip. Just turned it off. Hopefully it will solve the issues which I have just on MacBook, iPhone works OK.
ChuckMcM 10y ago
For what its worth some hotels have been known to intentionally degrade network performance / access to push people to the hotel supplied service. That has included screwing up people trying to stream video into their room via the network rather than buying the PPV movies that the Hotel provides. Either of these failure modes have a good chance of degrading the viewing experience of streaming video sufficiently to make it unusable. If you are in a hospitality situation you can demand a refund on your Internet charges, or if the Internet is "free" consider asking for a discount on your bill. That said, power line networking (the author mentioned devolo) is notoriously fraught with challenges. A company I helped start was acquired by the folks who put power line networking on the map (Tut Systems) and their were a lot of interesting interference sources they tried to mitigate. Inductive loads (motors) coming on and off was a big challenge, and places like hotels would have large fans that would circulate air through the common areas or hallways. Fluorescent lights were another noise source. All in all it was a poor excuse for a network and everyone was amazed they got a megabit per second point to point through it reasonably reliably.
giovannibajo1 10y ago
I think there's also an issue of easy diagnostic. It's extremely hard for non-tech people to assess the quality of the network; they basically have to rely on "time to open google" which is obviously a complicated metric to rely upon, and can be measured only with a manual test. Wifi has a single quality indicator, the "signal power" which is useful but doesn't say it all (it doesn't even take SNR into account). Somebody should come up with a monitoring algorithm, possibly mixing radio stats and stability of pings, that converts into a simple indicator on the UX of all operating systems. Something like green/yellow/red. Once people know their connection is "always red with MacBooks", they will fix it; hotel managers can ask for support from suppliers, airbnbs can go to the mall where they bought the router and complain. This would be up to the Wifi Alliance to fix, but they are the worst slow-moving committee ever seen on this planet, so I'm not holding my breath. They're probably implementing a new useless encryption algorithm that will be broken in 5 minutes and stay broken for another 5 years till they agree on something else.
- jstanley 10y ago
  If you do this, please make it a continuous scale rather than green/yellow/red. There's a big difference between "the worst that connection can get you a green" and "a really good connection".
  - Senji 10y ago
    I suggest we express it in dBs. :^)
    - tomchuk 10y ago
      Or an S meter - https://en.wikipedia.org/wiki/S_meter https://en.wikipedia.org/wiki/S_meter
- d33 10y ago
  This begs a question: could Wifi Alliance be replaced on this one? Assuming open source software (Linux PC + OpenWRT router), could this be implemented manually? I once contacted Wifi Alliance regarding this one: https://github.com/d33tah/call-for-wpa3 https://github.com/d33tah/call-for-wpa3 This was their response: > Thank you for contacting Wi-Fi Alliance. > > In regards to your question about work on security developments, there is a member task group that is working to advance Wi-Fi security enhancements. You can find all the current work groups on the Wi-Fi Alliance website at http://www.wi-fi.org/who-we-are/current-work-areas. > > In order to participate in discussion and work groups, companies must become a member of Wi-Fi Alliance.
gambiting 10y ago
I've found that in 90% of the cases where packets are dropped randomly on a consumer-level access point, the automatic channel selection is to blame. Go to settings, select a static channel number, and the problem disappears completely.
- rubberroad 10y ago
  90% is probably too generous. I tried static channel selection on two wifi routers with the same issues described here and it does not fix the issue.
- mjn 10y ago
  In my case it doesn't seem to be the wifi side of things, but the routing side of things that's causing trouble. I can consistently ping the local AP itself, but the connection to the internet has periodic dropouts.
anotheryou 10y ago
My router stops working about once a day, but only if Apple products are connected (not sure yet if iPhone or macbook (they often come in pairs), but it's consistent across 4 flatmates).
nikropht 10y ago
Check out the Mikrotik routers www.routerboard.com these are linux based and rock solid. The HAp AC Lite retails for $50 https://routerboard.com/RB952Ui-5ac2nD https://routerboard.com/RB952Ui-5ac2nD Also these routers are like swiss army knives they can do everything from DHCP Server to full BGP and MPLS. The only limitation is the CPU, Ram and the Interfaces.
digi_owl 10y ago
I dunno about the first, but the second looks oddly reminiscent of when i had a N800 and the router at home didn't have a first clue about wifi power saving. IIRC how wifi does it is that the device signals the router and then shuts down the radio for some 100s of ms. This indicated to the router to hold the packets. Now if the router do not have a clue about the signal, it would likely treat the device as gone. So when it comes back on and expects to continue from where it left off, the router gets royally confused. Not sure why doing a dhcp request would fix it though, but then i have not the first clue about OSX innards.
whatever_dude 10y ago
I wonder how many of those could be fixed by simply rebooting the router. I've had numerous problems with my own Time Warner Cable modem/router. It'd always become pretty bad after about 3 days of operation, dropping my speed to about 2% of what it was initially. I spend months debugging the damn thing, using a custom router, swapping cables, etc, and nothing would fix it. Until I got a timer and got it to reboot every day at 3 am (the https://xkcd.com/1495 https://xkcd.com/1495 route) and never had the problem again.
- oz 10y ago
  Was a 2% drop really that noticeable?
  - chadwittman 10y ago
    I think OP is saying it dropped to 2% from 100%. If you remove the "about" and think about it as an estimate, and focus on the "to"... it makes more sense: "Dropping my speed to ~2% of what it was initially".
    - whatever_dude 10y ago
      Yes, this. My download speed, measured after a reboot, was 50mbps. It would then drop to ~1mbps after a few days and stay there.
- digi_owl 10y ago
  Rebooting a router is not always an option. Both examples are from "public" wifi where the person with the problem is unlikely to be the only user.
  - jo909 10y ago
    Probably a 5 minute downtime at 4 AM is overall preferable to a continuously unstable connection. Of course an entity like a hotel should just pony up the money for better hardware, but I could excuse that for an (Air)BnB or guest house or vacation apartment.
IntelMiner 10y ago
I had a similar issue to this some time ago. I upgraded our internet at home to Comcast's 250 megabit package, in doing so I had to upgrade our modem. I picked up a Motorola/Arris Surfboard 6183 I ended up with an interesting issue where the modem itself would "hang". My ping to Google would skyrocket from 5ms to 3000ms+, my download speed would drop from 250~ megabits to 0.20, the upload speed however would remain constant at about 30Mbps Rebooting anything and everything had no effect, throwing various kinds of routing equipment in front of the modem (from OpenWRT to PF sense to even OpenBSD) made no difference. Eventually I purchased a "KanKun SmartSwitch". Some cheap Chinese wall adapter that you could power devices on and off using a phone app. Conveniently it ran OpenWRT and was hackable, so I was able to automate simply rebooting the modem when pings spiked into the 4 digit range (pinging Google every 60 seconds with a simple bash script) I spent months talking to various Comcast departments. Technical Support, Tier 2, Tier 3, NOC, Headend, Engineering. Eventually I was told that (across the 14 states in my "division") there's only about 20,000 of the model of modem I had, simply not enough to be able to establish a problematic pattern (presumably most customers would just reboot the device when it crashed Frustrated, I noticed on the Amazon store page that there were numerous complaints about the device with the same issue. I assumed it most likely to be a firmware issue, as the headend engineering team could not correlate any changes from my device on the node at the timestamps I gave them, still archived here http://intelminer.com/reboot.txt http://intelminer.com/reboot.txt Upon speaking to Amazon about a refund or exchange, they referred me to Arris/Motorola citing it was under warranty. Arris/Motorola then "helpfully" explained that they certify everything BUT the software of the device to be functional, as such I was not covered under warranty. (But hey why not buy a Surfboard 6190 instead? it IS newer!) It seems like almost a racket for planned obsolescence. Release a decent modem, hire some interns to write crap software, then encourage the customer to "upgrade" the "faulty" hardware when they call in. After all, it's not under warranty now is it?
- hx87 10y ago
  > "helpfully" explained that they certify everything BUT the software of the device to be functional Perhaps because your ISP is responsible for providing and flashing the modem's firmware? That being said, I don't exactly trust Comcast to provide reliable software for my modem.

178 points by mjn 10y ago

Every free wifi I have ever been on has been broken like this in one way or another, crazy ping times, randomly dropped packets or just extremely slow etc. In fact I am writing this right now from an Amtrak train but tethered to my phone since the free wifi is so bad.

userbinator 10y ago
If it's truly free (and often even otherwise) there's probably a dozen or more others sharing the same access point as you.
jsight 10y ago
I think Amtrak uses cellular connections to the outside internet. Depending upon the part of the country, there is a good chance that the weak point is their link to the cellular network.
- mindslight 10y ago
  It seemed like Amtrak uses Verizon for backhaul, at least on the Lake Shore Limited. It definitely goes through some spotty coverage areas. Personally I couldn't care less about their wifi though - I appreciate the power outlets much more.

gefh 10y ago

I had exactly the same problem with OSX - all other devices were fine but my macbook would drop packets after 30 seconds or so. Only fix seemed to be a new router. No problems since.

mjn 10y ago
Interesting! I looked quite a bit to see if there was anything OSX-specific that anyone else online had documented, but nothing I turned up seemed to pan out. I am reasonably certain that the ultimate culprit here is bad low-end wifi devices that either suffer from bad hardware (too little RAM, etc.) or bad software (some poorly tested customized version of embedded Linux), or both. But I'm really curious why only OSX seems to cause the problem to manifest in several of these cases.
- hug 10y ago
  Your article doesn't mention it: Have you tried using a statically assigned IP address? (Poor etiquette inside the DHCP range, but maybe if you just snarf the IP you've already leased..) I ask this because OS X's DHCP stack is known to exhibit some strange and unfriendly behaviours: http://cafbit.com/entry/rapid_dhcp_or_how_do http://cafbit.com/entry/rapid_dhcp_or_how_do
  - mjn 10y ago
    I did try that (though you're right that it's not in the article), setting the last DHCP address I'd received as static IP, but it doesn't seem to change anything. Still the same dropouts every ~30 seconds.
    - seiferteric 10y ago
      Maybe try force sending gratuitous ARP's every 10 seconds? Also it might be interesting looking at a packet capture from both android and mac laptop to see what the difference is.
- cotizo 10y ago
  Hi mjn! I am living in the UK at the moment, and I'm occasionally experiencing the very same issue. My OSX device randomly drops packets (for 30s at a time), while my Android phone has no issues. I am connecting to the internet via a broadband wifi router. I tried rebooting the router, but that does not always resolve the problem. However, when I reboot the Mac, the problem goes away for at least a couple of days.
the_mitsuhiko 10y ago
All UPC spplied routers in Austria have that issue. Does not matter whichbwifi is connected. Thr only way I could fix his is to put a second NAT up and have it make a new dhcp server below it. It's a well know problem that neother apple nor tompson are fixing :(
- xhruso00 10y ago
  UPC customer here as well, good to find I am not alone. Has this been reported to them?
  - the_mitsuhiko 10y ago
    I talked to the Austrian version of it and they seem useless. I don't think they understand there is a problem but as far as I understand it's the same story in other countries as well.

darkengine 10y ago

I used to frequent a coffee shop with a router that would refuse to let my laptop's wifi card connect about half the time. Like the author, my phone could connect but it would simply not respond to any attempts to connect from my laptop, whether booted into Windows or OpenBSD. The only solution was to ask the barista to reset the router, which was all the more frustrating when they refused to do it because everyone else could connect just fine.

ballooney 10y ago
That seems like the readonable answer on the part of the barista.

userbinator 10y ago

The details are vague but if I remember correctly, this is due to something OS X does with DHCP that isn't quite standard but apparently helps to make connection resumption faster --- when it works, that is.

MBCook 10y ago
I seem to remember this. Was it that OS X started using its old lease while waiting for it to renew under the assumption that it would probably get the same thing and be fine?
- hug 10y ago
  That's almost exactly the case. Link here: http://cafbit.com/entry/rapid_dhcp_or_how_do http://cafbit.com/entry/rapid_dhcp_or_how_do Previous HN discussion here: https://news.ycombinator.com/item?id=2755461 https://news.ycombinator.com/item?id=2755461

rubberroad 10y ago

Same problems for me, experienced this a lot on my home wifi, using a dual band, modem / wifi router combo. Problems ONLY occurred on my MacBook Pro, no other devices. Purchasing a dedicated modem and using an Apple AirPort Extreme was the only thing that resolved the issue, which annoyed me and made me feel like Apple is further locking me into their ecosystem of devices.

tw04 10y ago
MBPs don't support certain channels which is maddeningly frustrating. Trying to find from my notes which channels those are, but when I finally changed from auto to hard-setting to channel 100, all my issues with MBPs on my network went away.
- xhruso00 10y ago
  Can you please find the list? I think there are just 13 channels (or 11 depends where you are) 2.4Ghz
  - tw04 10y ago
    Still can't find it. I haven't had issues on 2.4ghz, this is on 5ghz. This thread seems to cover about the same thing I discovered: https://www.reddit.com/r/apple/comments/2zo1uo/if_you_have_still_having_wifi_issues_with/ https://www.reddit.com/r/apple/comments/2zo1uo/if_you_have_s...
- SysArchitect 10y ago
  There are certain channels in the 5Ghz range that require the access point to do checking to make sure they don't actively interfere with radar... See here for a document from Cisco describing the issue: http://www.cisco.com/c/en/us/td/docs/routers/access/3200/software/wireless/3200WirelessConfigGuide/RadioChannelDFS.pdf http://www.cisco.com/c/en/us/td/docs/routers/access/3200/sof... interestingly enough, hard setting the channel to 100 might violate FCC regulations, and DFS should still be used...
  - 10y ago

wtracy 10y ago

My own Linksys router (I think it's a WRV200) occasionally starts to silently drop new connections until I disconnect and reconnect. If my browser has an http/2 connection open, I can continue to browse that particular site, but when I navigate to another site, the browser times out. It seems to only affect one device at a time. Curiously, the behavior became dramatically more frequent (from once every few months to several times a week) when I moved in with family, which meant plugging it into a different modem, and adding a bunch of Windows devices to the network. (When I move back out, I'll probably leave this router behind and get myself something that runs Tomato.)

userbinator 10y ago
That sounds like the NAT table has filled up. Incidentally, this is often the cause of problems with "routers" that people experience --- it's not the (IP) routing part that's giving trouble, as that's stateless and involves not much more than packet forwarding. Things like NAT do involve state, since the router has to assign a port mapping and keep track of (TCP) connection lifetimes. If connections aren't closed correctly or the router misses detecting them for whatever reason, the port mappings will stay in the table until they time out (which may take hours or more) or the "router" is rebooted. The problem becomes more frequent the more devices there are on the network which are making connections.

ploxiln 10y ago

Here's a theory based on a bunch of un-substantiated and un-researched facts: Some routers do not allow traffic from IPs which are not active DHCP leases. When DHCP lease expires, they block traffic. But many routers don't enforce this. Some routers give out super short DHCP leases - as short as 30 seconds. But the typical length is 12 or 24 hours. A public or semi-shared wifi router is more likely to use these policies to prevent exhausting the local subnet address pool, which is typically around 254 addresses. Mac OS X doesn't believe that renewing a DHCP lease in 30 seconds is ever really necessary, limits the renewal frequency to once per minute. I'd check the dhcp lease time.

mjn 10y ago
An intriguing and plausible theory! In my case though it seems that the lease is 86400 seconds (24 hours), or at least that's what the router is claiming to give out. So I don't think this is it. My guess is that renewing the DHCP lease has some side effect of resetting the session, rather than it being the actual DHCP lease renewal that is important.
hug 10y ago
Definitely unsubstantiated: If this is just at an AirBnB, it's probably not going to be a commercial wifi system. On your topic, though, Princeton noticed something similar with regards to iOS and DHCP, although it is several years old now: https://www.net.princeton.edu/apple-ios/ios41-allows-lease-to-expire-keeps-using-IP-address.html https://www.net.princeton.edu/apple-ios/ios41-allows-lease-t... (last tested version was iOS 6.1)
smellf 10y ago
Are you serious? A 30 second lease is insane. I've seen DHCP servers that TAKE 60 seconds to give a lease.
- JoeAltmaier 10y ago
  Was that the server, or the client waiting that long? THe DHCP spec requires the client to broadcast a request, then wait for a while (unspecified) and collect answers, then choose the best answer (metric unspecified). Sometimes when I write DHCP clients I choose the metric as "fastest", then just choose the first answer and don't wait for any more. And it takes on average a few milliseconds to get a lease.

ggggggggggw 10y ago

For those who are curious, there's a bunch of reasons that contribute to why consumer wifi routers sucks ass: 1. Wifi routers are very complicated. You need smart people at all levels of the stack to build a modern wifi router. You need people who know 802.1ac like the back side of their hand, people who know how to set up and deploy linux environments, embedded engineers for debugging OEM driver issues, networking gurus for handling the voodoo in levels 2-4 of the OSI stack, application people for rolling the user interface, cloud people for cloud support. Normally this isn't a big deal, if it wasnt for the next point 2. The profit margins on consumer routers are complete trash. Even if you're one of the big boys with double digit market share, you're going to have a very hard time keeping a decent engineering team staffed and your marketing team staffed at the same time while still breaking even. 3. Consumer router sales are SKU driven. There are dozens of price and performance points you have to hit to meet the demands of the consumer market. You cannot make be profitable with less than 10 actively selling SKUs. Every time you release a new SKU, it's a new opportunity for marketing to try to sell the device to brick and mortar stores that they're trying to expand into. If you aren't releasing 5-6 SKUs each year, you're going to have a very hard time keeping your router on store shelves. 4. Since sales are SKU driven and your engineering team is probably under funded, you have the exciting problem of maintenance releases. If your company has 50 supported SKUs and you find a non-driver issue in one of them, the chances are that it affects 10 other SKUs as well, if not all of your other SKUs. Pushing that maintenance firmware to 50 SKUs could easily take 6 months of combined QA or Firmware development time. As far as your marketing department is concerned, all that time you spend on maintenance releases is time that isn't spent on making new SKUs with exciting new features. tldr: get a business class wifi router

shmerl 10y ago
For home usage, high end consumer routers with free firmware work just fine (something like Linksys WRT1900ACS with DD-WRT / OpenWRT).
- zippergz 10y ago
  Admittedly I haven't tried the newest models, but my experience with Linksys hardware and either ddwrt or tomato was pretty bad. Run for a couple of days and then require a power cycle. Seemed like a hardware issue.

zeta0134 10y ago

I wish he would drop the name of the router he's running into these issues on. I have the same exact issue with my laptop (random disconnects for 30 seconds) only on my home router, and I've been considering replacing the router with something of higher quality. I use an ASUS 750N, which is starting to show its age faster than I expected, but otherwise services the devices in my house just fine. Except for my laptop, which is the only device I actually need to use over wifi on a regular basis.

givinguflac 10y ago
I don't think the model is 750N, more likely that's the max speed. Probably you have the 56u or 66u. The Merlin firmware for Asus routers has really improved my experience with the ac-87u. It keeps the stock UI and fixes bugs/adds features. https://asuswrt.lostrealm.ca https://asuswrt.lostrealm.ca
- zeta0134 10y ago
  You're quite correct, the 750N was from memory. The actual model is an RT-N65R. That firmware looks lovely! I will give that a whirl when I have time to dink around with it, possibly this weekend. Thanks for that!
  - givinguflac 10y ago
    Happy to help out :)
- mieko 10y ago
  asuswrt-merlin is awesome. I replaced my ISP's shitty combo router with a barebones TP-Link DSL modem and an Asus AC5300 (which physically looks ridiculous) running asuswrt-merlin. It turned one of the more annoying parts of my day into, eh, nothing. It just works flawlessly for months on end.

microcolonel 10y ago

I experience basically the same level of problems on our office's Cisco Meraki gateway/firewall. A couple months ago we had to do a support ticket to get them to fix their spanning-tree implementation because it configured loops in our simple dual-master crossover switch configuration, forcing us to disable one of the masters. Then there was a spurious packet loss problem in one of the default configuration parameters. Now it just randomly stalls TCP connections open until the local node closes them, but allows the remote node to continue receiving packets(!), which is probably the worst thing a TCP system can do aside from simply not connecting. I quite literally had to attempt this post twice before giving up and connecting to a UDP VPN. I have watched my colleagues cancel and refresh webpage loads for the last few months.

jonatron 10y ago
I've had all sorts of problems with Meraki APs. They claim to hop around to find the clearest channel, but they all always chose channel 44. Manual channel selection was limited to non DFS channels, otherwise they'd switch back to channel 44. There was no insight into CPU usage, so we were suspicious that some QoS settings made everything grind to a halt, but we couldn't confirm. Switched to high end Ruckus APs and a Juniper router/firewall and it's now working properly.

gpm 10y ago

These aren't even that bad. I've had a router start sending me two DHCP offers, with different IPs. The first offer containing an IP outside the range it was supposed to allocate. After my computer tried to accept the first offer, the router started ignoring me. This behavior survived rebooting the router (and everything else involved), flushing the DHCP table fixed it for some reason.

voltagex_ 10y ago
I have a TP-Link Archer D9 on the "latest" firmware that will either: 1) stop giving out leases 2) suffer catastrophic failure in miniupnpd and stop allowing port forwarding This is a $200AUD device and it's utter trash.

deleted 10y ago

[deleted]

colanderman 10y ago

MacBooks have issues with WMM (WiFi QoS). I've seen my connection drop for dozens of seconds at a time when I enable WMM on my router. Selectively disabling it for my Mac (leaving it on for my wife's Lenovo and my HTPC) fixes the issue.

xhruso00 10y ago
Thanks for tip. Just turned it off. Hopefully it will solve the issues which I have just on MacBook, iPhone works OK.

ChuckMcM 10y ago

For what its worth some hotels have been known to intentionally degrade network performance / access to push people to the hotel supplied service. That has included screwing up people trying to stream video into their room via the network rather than buying the PPV movies that the Hotel provides. Either of these failure modes have a good chance of degrading the viewing experience of streaming video sufficiently to make it unusable. If you are in a hospitality situation you can demand a refund on your Internet charges, or if the Internet is "free" consider asking for a discount on your bill. That said, power line networking (the author mentioned devolo) is notoriously fraught with challenges. A company I helped start was acquired by the folks who put power line networking on the map (Tut Systems) and their were a lot of interesting interference sources they tried to mitigate. Inductive loads (motors) coming on and off was a big challenge, and places like hotels would have large fans that would circulate air through the common areas or hallways. Fluorescent lights were another noise source. All in all it was a poor excuse for a network and everyone was amazed they got a megabit per second point to point through it reasonably reliably.

giovannibajo1 10y ago

I think there's also an issue of easy diagnostic. It's extremely hard for non-tech people to assess the quality of the network; they basically have to rely on "time to open google" which is obviously a complicated metric to rely upon, and can be measured only with a manual test. Wifi has a single quality indicator, the "signal power" which is useful but doesn't say it all (it doesn't even take SNR into account). Somebody should come up with a monitoring algorithm, possibly mixing radio stats and stability of pings, that converts into a simple indicator on the UX of all operating systems. Something like green/yellow/red. Once people know their connection is "always red with MacBooks", they will fix it; hotel managers can ask for support from suppliers, airbnbs can go to the mall where they bought the router and complain. This would be up to the Wifi Alliance to fix, but they are the worst slow-moving committee ever seen on this planet, so I'm not holding my breath. They're probably implementing a new useless encryption algorithm that will be broken in 5 minutes and stay broken for another 5 years till they agree on something else.

jstanley 10y ago
If you do this, please make it a continuous scale rather than green/yellow/red. There's a big difference between "the worst that connection can get you a green" and "a really good connection".
- Senji 10y ago
  I suggest we express it in dBs. :^)
  - tomchuk 10y ago
    Or an S meter - https://en.wikipedia.org/wiki/S_meter https://en.wikipedia.org/wiki/S_meter
d33 10y ago
This begs a question: could Wifi Alliance be replaced on this one? Assuming open source software (Linux PC + OpenWRT router), could this be implemented manually? I once contacted Wifi Alliance regarding this one: https://github.com/d33tah/call-for-wpa3 https://github.com/d33tah/call-for-wpa3 This was their response: > Thank you for contacting Wi-Fi Alliance. > > In regards to your question about work on security developments, there is a member task group that is working to advance Wi-Fi security enhancements. You can find all the current work groups on the Wi-Fi Alliance website at http://www.wi-fi.org/who-we-are/current-work-areas. > > In order to participate in discussion and work groups, companies must become a member of Wi-Fi Alliance.

gambiting 10y ago

I've found that in 90% of the cases where packets are dropped randomly on a consumer-level access point, the automatic channel selection is to blame. Go to settings, select a static channel number, and the problem disappears completely.

rubberroad 10y ago
90% is probably too generous. I tried static channel selection on two wifi routers with the same issues described here and it does not fix the issue.
mjn 10y ago
In my case it doesn't seem to be the wifi side of things, but the routing side of things that's causing trouble. I can consistently ping the local AP itself, but the connection to the internet has periodic dropouts.

anotheryou 10y ago

My router stops working about once a day, but only if Apple products are connected (not sure yet if iPhone or macbook (they often come in pairs), but it's consistent across 4 flatmates).

nikropht 10y ago

Check out the Mikrotik routers www.routerboard.com these are linux based and rock solid. The HAp AC Lite retails for $50 https://routerboard.com/RB952Ui-5ac2nD https://routerboard.com/RB952Ui-5ac2nD Also these routers are like swiss army knives they can do everything from DHCP Server to full BGP and MPLS. The only limitation is the CPU, Ram and the Interfaces.

digi_owl 10y ago

I dunno about the first, but the second looks oddly reminiscent of when i had a N800 and the router at home didn't have a first clue about wifi power saving. IIRC how wifi does it is that the device signals the router and then shuts down the radio for some 100s of ms. This indicated to the router to hold the packets. Now if the router do not have a clue about the signal, it would likely treat the device as gone. So when it comes back on and expects to continue from where it left off, the router gets royally confused. Not sure why doing a dhcp request would fix it though, but then i have not the first clue about OSX innards.

whatever_dude 10y ago

I wonder how many of those could be fixed by simply rebooting the router. I've had numerous problems with my own Time Warner Cable modem/router. It'd always become pretty bad after about 3 days of operation, dropping my speed to about 2% of what it was initially. I spend months debugging the damn thing, using a custom router, swapping cables, etc, and nothing would fix it. Until I got a timer and got it to reboot every day at 3 am (the https://xkcd.com/1495 https://xkcd.com/1495 route) and never had the problem again.

oz 10y ago
Was a 2% drop really that noticeable?
- chadwittman 10y ago
  I think OP is saying it dropped to 2% from 100%. If you remove the "about" and think about it as an estimate, and focus on the "to"... it makes more sense: "Dropping my speed to ~2% of what it was initially".
  - whatever_dude 10y ago
    Yes, this. My download speed, measured after a reboot, was 50mbps. It would then drop to ~1mbps after a few days and stay there.
digi_owl 10y ago
Rebooting a router is not always an option. Both examples are from "public" wifi where the person with the problem is unlikely to be the only user.
- jo909 10y ago
  Probably a 5 minute downtime at 4 AM is overall preferable to a continuously unstable connection. Of course an entity like a hotel should just pony up the money for better hardware, but I could excuse that for an (Air)BnB or guest house or vacation apartment.

IntelMiner 10y ago

I had a similar issue to this some time ago. I upgraded our internet at home to Comcast's 250 megabit package, in doing so I had to upgrade our modem. I picked up a Motorola/Arris Surfboard 6183 I ended up with an interesting issue where the modem itself would "hang". My ping to Google would skyrocket from 5ms to 3000ms+, my download speed would drop from 250~ megabits to 0.20, the upload speed however would remain constant at about 30Mbps Rebooting anything and everything had no effect, throwing various kinds of routing equipment in front of the modem (from OpenWRT to PF sense to even OpenBSD) made no difference. Eventually I purchased a "KanKun SmartSwitch". Some cheap Chinese wall adapter that you could power devices on and off using a phone app. Conveniently it ran OpenWRT and was hackable, so I was able to automate simply rebooting the modem when pings spiked into the 4 digit range (pinging Google every 60 seconds with a simple bash script) I spent months talking to various Comcast departments. Technical Support, Tier 2, Tier 3, NOC, Headend, Engineering. Eventually I was told that (across the 14 states in my "division") there's only about 20,000 of the model of modem I had, simply not enough to be able to establish a problematic pattern (presumably most customers would just reboot the device when it crashed Frustrated, I noticed on the Amazon store page that there were numerous complaints about the device with the same issue. I assumed it most likely to be a firmware issue, as the headend engineering team could not correlate any changes from my device on the node at the timestamps I gave them, still archived here http://intelminer.com/reboot.txt http://intelminer.com/reboot.txt Upon speaking to Amazon about a refund or exchange, they referred me to Arris/Motorola citing it was under warranty. Arris/Motorola then "helpfully" explained that they certify everything BUT the software of the device to be functional, as such I was not covered under warranty. (But hey why not buy a Surfboard 6190 instead? it IS newer!) It seems like almost a racket for planned obsolescence. Release a decent modem, hire some interns to write crap software, then encourage the customer to "upgrade" the "faulty" hardware when they call in. After all, it's not under warranty now is it?

hx87 10y ago
> "helpfully" explained that they certify everything BUT the software of the device to be functional Perhaps because your ISP is responsible for providing and flashing the modem's firmware? That being said, I don't exactly trust Comcast to provide reliable software for my modem.