Linksys WRT Routers Won't Block Open Source Firmware, Despite FCC Rules (arstechnica.com)

The FCC requires all manufacturers to prevent users from having any direct ability to change RF parameters (frequency limits, output power, country codes, etc). The easiest way for a router manufacturer to comply with FCC's guideline is to block the open source router firmware -- which is what TP-Link has been doing. But thankfully, at least one router manufacturer doesn't think blocking the firmware is the right way to go about it. Ars Technica reports: Linksys has been collaborating with chipmaker Marvell and the makers of OpenWrt to make sure its latest WRT routers can comply with the new rules without blocking open source firmware, company officials told Ars. Linksys' effort stands in contrast with TP-Link, which said it would entirely prevent loading of open source firmware on its routers to satisfy the new Federal Communications Commission requirements. "They're named WRT... it's almost our responsibility to the open source community," Linksys router product manager Vince La Duca told Ars. Cybersecurity experts have urged the router manufacturers to not block open source firmware.

Comments

Excellent

[Anonymous Coward]

Excellent decision. I know what my next router will be.

Re:Excellent

[negRo_slim]

While I'm not sure I'll go with Linksys, I am certainly disappointed I picked up a TP Link right before all this came to light. At least I can enjoy knowing that most people only buy TP Link to flash custom firmware and their foolish decision will most likely hurt their bottom line.

I still don't understand what lead to all this, I highly doubt putting a few more milliwatts out or using a few MHz on either side of the allotted spectrum was causing much (if any) actual harm.

Re:Excellent

[Anonymous Coward]

No. Fuck no. People are morons and we must not let people decide if it's OK to "[put] a few more milliwatts out" or using parts of the spectrum they're not supposed to. That's begging for localized shouting matches and overuse of allocated spectrum... where both are problems we already have.

The FCC absolutely did the right thing here, and so is Linksys.

Re:Excellent

[Solandri]

I still don't understand what lead to all this, I highly doubt putting a few more milliwatts out or using a few MHz on either side of the allotted spectrum was causing much (if any) actual harm.

The "open" 5 GHz band spans from 5030 - 5835 MHz. Right smack dab in the middle of it at 5600 MHz is terminal doppler weather radar. That's one of the radars used to make the pretty rainfall pics you see on the news reports. More crucially, airports use it to detect wind shear conditions which have brought down several airliners in the past.

The problem is, because it's doppler radar, the frequency shift of the radar signal is crucially important, not just the return signal strength. So the FCC has carved out a band from 5250 - 5730 MHz and declared it DFS - dynamic frequency selection. Equipment can use these open frequencies, but if they do they have to monitor to see if weather radar is being used, and immediately shift to a different frequency outside this band if they detect weather radar.

A few routers do implement this frequency shifting. The vast majority simply block out those frequencies in their firmware (which is why your 5 GHz channel selection is limited to channels 36-48 and 149-165). But most third party firmwares are made in countries which don't have airports with TDWR radar (in fact most U.S. airports don't yet), so their governing agencies don't restrict these frequencies, so the firmware authors make no effort to limit use of these frequencies. Loading the third party firmware onto a router in the U.S.allows your router to spam these frequencies indiscriminately, leading to TDWR possibly being unable to detect wind shear or detecting it later than it could have without the interference, possibly causing another airliner to crash.

Re:Excellent

[Anonymous Coward]

Excellent explanation. Visually, devices that interfere with TDWR displays appear as a wedge that is several degrees wide. The wedge obscures everything from the center of the display to the edge. Here's an example:

http://fpvlab.com/forums/attachment.php?attachmentid=69438&d=1452686140

Re:Excellent

[EndlessNameless]

There is finite usable spectrum, and Wifi had to go somewhere.

Usable spectrum in this case means:

* not absorbed by the atmosphere
* reasonable effective range per unit power
* harmless to organic tissues
* capable of penetrating typical construction materials

If you're aware of an unallocated band that you think the FCC has overlooked, feel free to contact them to ensure the oversight is corrected.

Re:Excellent

[danbob999]

The problem with the new WRT routers is that they sell for twice the value of comparable hardware from other vendors. And if you look carefully, you can find models which are just as good, if not better, in running 3rd party open source firmwares such as OpenWRT.
The original WRT54G was cheap, that's why it succeeded.

Re:Excellent

[Solandri]

* not absorbed by the atmosphere

Actually, 2.4 GHz and 5 GHz were chosen because they're absorbed more by the atmosphere. 2.4 GHz matches up closely with the resonance of water molecules (which is why microwave ovens operate at 2.45 GHz - they heat up food by pumping energy into the water molecules). And 5.6 GHz is absorbed readily by raindrops for some reason I haven't yet been able to learn (which is why it's handy for weather radar).

Broadcasts on both bands thus attenuate more quickly relative to other frequencies. This not only makes them less useful for long-distance transmissions, but it makes them ideal for unregulated transmissions. The signal blasted by an unregulated device at these frequencies doesn't travel as far through the atmosphere, so the radius of its noise footprint is smaller compared to a different frequency. Basically, you can squeeze more devices closer together without interfering with each other at these frequencies. Both of these "features" make them ideal choices for open frequencies.

Re:A good decision

[Anonymous Coward]

This action is not a violation of the FCC rule in question. That rule defined a chain of responsibility for purposes of assigning blame when and only when someone is using their wireless router beyond the scope of FCC approved frequency/intensity ranges.

For a fine to come about, someone has to flash the firmware (easy it seems) with another firmware that does not respect the FCC mandated boundaries (I think that would require changing the source and recompiling for most of them) and then pick a frequency and power level that is prohibited for WiFi use.
While I forget the order of blame that the FCC decided on, this announcement indicates that Linksys has run the numbers and determined that the increased fanaticism from OSS enthusiasts for their routers will more than offset any anticipated culpability when people misuse their hardware.

Summary

[DrYak]

The FCC rules do not mandate, either directly or indirectly, that OS firmware be blocked.

Which was already explained in the Summary.

I know this is /. and nobody reads TFA, but you could at least read a little bit past the title and at least read the summary.

A title has limited number of words and characters: "despide FCC rulins" is as mush as the author managed to cram into it.

And the FCC *IS* causing most manufacturer to lock their firmware. FCC doesnt madante litteraly against opensource and user-upgradeable firmware, but the ruling is strict. No unlawful signal shall be emitted by a device. Under no circumstances.

- Either a manufacturer has to jump through some complex hoops to find a solution which both open and user accessible (following the spirit of the GPL license used by some component. And litteraly following GPLv3) AND at the same time prevent the end-user from emitting signals that fiolated FCC rules (e.g.: emitting on a EU-only frequency in USA).

- Or the manufacturer could just lock everything in a box, and only let cryptographically-signed firmwares in, and call it a day. (and hope no GPLv3 got violated in the process).

Nearly every constructor goes for the latter. Only LinkSys Fritz and a few other go for the former

Features

[Frederic54]

I do not not install a 3rd party firmware to use channel 13 or crank power output, but for features:

• Wireless bridge
• OpenVPN client
• OpenVPN server
• Powerful QOS
• IP traffic monitoring
• IPv6
• Multiple SSID
• Full USB support (printer, HDD, 4G, etc)
• VLAN
• MultiWAN
• etc

All this on a $79 router.