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Hidden Networks in TP-Link Routers

jahed.dev

171–180 of 230 posts

Re: Hidden Networks in TP-Link Routers

#171

> Maybe it's finally time to build my own router Can anyone link a good "getting started" guide for this? I have experience managing servers but not managing network appliances, so I'm looking for a relatively gentle intro... Edit: I'm not asking about how to install OpenWRT on an existing router, I'm looking for a guide on how to build a router from general purpose hardware - in the same way that you can build your…

My preference is to install Proxmox on a small x86 machine with enough NICs and virtualize OpenWRT. One could also virtualize OPNSense (or VyOS, which I ran previously), but for me, OpenWRT is enough. I use this to route gigabit WAN: https://www.reddit.com/r/homelab/comments/hzvfih/new_router_...

Thank you! I didn't consider the virtualisation route, interesting. I saw many of those "industrial mini PC" on eBay, but for now I'm planning to repurpose old hardware (discarded parts taken out of my gaming PC over time due to updates, I have everything I need to build a new machine except NICs and case).

PS just followed the AliExpress link, those prices are good

Re: Hidden Networks in TP-Link Routers

#172
post #81

Earlier quoted context omitted.

Sadly OpenWRT doesn’t support band steering.

If you set the SSID and password identical for both bands, the clients should prefer to negotiate the optimal band. I just checked and all clients save for some legacy devices on my OpenWRT router are on 5GHz. So I'm now wondering for which cases is band-steering helpful?

Clients don't always do this automatically. My Arch Linux laptop would often select 2.4GHz in places where 5GHz offered a much better experience. Generally it will start on 5GHz when it is close to the router, fall back to 2.4GHz when it moves far away, and (sadly) it doesn't go back to 5GHZ when it moves back closer to the router. Apple devices were pretty good, automatically choosing and switching to the best bands at all times with behaviour much similar to that seen on mobile phones. For this reason I prefer the AP to manage the band steering as it means all devices are connected to the best band. Leaving it to the clients results in a hit and miss experience depending on how well the decide operates. I live with other people who own all sort of different devices so it's not possible for me to say "OK this network is only for Apple devices", I have to ensure thr WiFi works for all sorts of different devices.

Re: Hidden Networks in TP-Link Routers

#173

Earlier quoted context omitted.

Yeah I used to get TP-Link because they were so well supported by openwrt and dd-wrt. But lately they've really become consumer hostile like with their smart plugs, removing local control functions so they can no longer be used with home automation systems :( For WiFi I moved to unifi but they're also becoming more difficult to work with. They are making it harder to use their stuff locally without their cloud servic…

In general, margins in hardware manufacturing are low. Companies will generally do anything they can to increase demand, and establishing a "moat" is a great way to inflate demand. "I have some stuff, but it only works with other stuff from this same company" sucks for us as buyers, but it's obviously great for the seller. This is also why literally every company ever says that repairing anything they sell will void…

>” This is also why literally every company ever says that repairing anything they sell will void the warranty unless you also buy all the parts from them unless the law expressly forbids them from doing so.”

No, manufacturers do that because they don’t want to have to fix products that you’ve hacked up, then guarantee the item’s safety and regulatory compliance.

Re: Hidden Networks in TP-Link Routers

#174
post #117

For those curious about the "Wi-Fi spam" comment: even though nothing is connected to the network and it's a hidden SSID, it still has to broadcast beacons every 100ms. The 802.11 standard says beacons must be sent at the lowest rate the AP supports, so your ~350 byte beacon at 1mbps (2.4 GHz) uses around 5% of the frequency. It doesn't take many SSIDs on the same 2.4 GHz channel to make the throughput fall through t…

Another, maybe bigger, problem is probe requests. A client device, e.g. smartphone, uses "active scanning" where it sends probe packets and asks "is there any AP in this channel?" instead of "passive scanning" where it would wait for beacons. Active scanning has the advantege of being much faster. In passive scanning, client needs to stay 200-300 ms in each channel and that ads up quickly when you consider 2.4 GHz and 5 GHz channels. So clients prefer to use active scanning to quickly discover APs. Some clients send periodic probe requests even when they are connected to an AP in case they need to switch to another AP. All these probe requests together with beacons pollute 2.4 GHz.

Re: Hidden Networks in TP-Link Routers

#175
We had the misfortune of having a large number of tp-link devices being installed in our network (a large residential building) and those devices have been nothing but a source of trouble ever since they were installed. They seem to be talking with each other and overriding their configuration to the point where I had to segregate them in their own little NATs (with the complete blessings of the building manager). Only then did the shenanigans stop.

That, in addition to their ever-dwindling configuration options, is why I refuse to buy from them anymore. There (much) older devices were fantastic though.

Re: Hidden Networks in TP-Link Routers

#176
post #117

For those curious about the "Wi-Fi spam" comment: even though nothing is connected to the network and it's a hidden SSID, it still has to broadcast beacons every 100ms. The 802.11 standard says beacons must be sent at the lowest rate the AP supports, so your ~350 byte beacon at 1mbps (2.4 GHz) uses around 5% of the frequency. It doesn't take many SSIDs on the same 2.4 GHz channel to make the throughput fall through t…

Would there have been a better way to do design beacons? The general problem is a device needing to advertise itself for other devices to connect to, other devices which might not be capable of any faster rate... Beacons being 350 bytes is pretty stupid though... They could have been 20 bytes long, saying "I'm a device with mac address XXX, plz contact me to know what services I have on offer".

Beacons also have to broadcast the DTIM which allows stations to come out of standby if there is data waiting for them. This can be up to 128 bytes. But I agree, beacons are stupidly fat. The basic beacon is quite small except for the additional tags. If you fire up wireshark you'll see the bulk of the bytes in broadcasting all kinds of feature nonsense that IMHO should only be broadcast during a request to join.

e.g the beacon frame is 24B on my Netgear, but the tagged paramters are 300 bytes. Sure, the SSID and DTIM are in there, but then there's a bunch of extended support rates, RSN info, HT info, and vendor specific stuff (Microsoft WMM/WME parameters, 3Com stuff... huh??)

Re: Hidden Networks in TP-Link Routers

#177
Worse still almost all new routers and mesh systems, don't have the admin interface on the device, you have to sign up and manage it through a cloud account controlled by the manufacture.

If anyone can recommend a good wifi mesh system that supports wifi 6 and doesn't require signing up for a manufacture cloud account, please let me know.

Re: Hidden Networks in TP-Link Routers

#178

Worse still almost all new routers and mesh systems, don't have the admin interface on the device, you have to sign up and manage it through a cloud account controlled by the manufacture. If anyone can recommend a good wifi mesh system that supports wifi 6 and doesn't require signing up for a manufacture cloud account, please let me know.

Ubiquiti access points support meshing and you can run the controller yourself. I have AP Lite 6.

Re: Hidden Networks in TP-Link Routers

#179
post #12

This type of whackery is (the primary reason) why I try to buy computing devices on which I can flash a clean OS (OpenWrt/DD-WRT for routers)[1]. It sucks because it limits my choices down to a few, but at the same time I feel like I don't throw out money at abandonware. [1] don't even get me started on TP-Link releasing routers with the same name but v2/v3/2020/2021 update where it's hard to even know if I'm buying…

Exactly. I have a nice TP-Link router that doesn't have the problem described in the article..because the first thing I did was to flash OpenWRT on it. Problem solved.

Re: Hidden Networks in TP-Link Routers

#180
post #95

Earlier quoted context omitted.

The author touched on right of repair. I’d love to see a law requiring all devices to either be supported, or if being sunset, being required by law to provide tools/source/schematics to take over the device and extend its utility beyond the manufacturer’s willingness. Particularly a last firmware that disables anything requiring phoning home to continue to function. We saw that with OnHub recently, when after only 6…

There is a specific problem with routers and certification for radio usage. This makes right to repair harder. It's not just a legal issue. The ether is quite full and it mostly works because there are clear rules that devices must meet. With user serviceable routers, bumping up power, or moving to locally forbidden (quieter) frequencies could become lifehacks. There was already an airport whose radio saw interferenc…

> There is a specific problem with routers and certification for radio usage.

No, there isn't, because it's perfectly possible to limit what frequencies and power levels the hardware can emit without affecting the ability to run custom firmware such as OpenWRT. The certification argument is a dodge used by router manufacturers to avoid having to give customers what they actually want.

> There was already an airport whose radio saw interference from extra powerful 5ghz wifi routers.

Anyone who is radiating enough power to interfere with airport radios is doing something a lot stranger than just flashing custom firware like OpenWRT on their router. Such people are easily stopped without having to lock down devices.

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