IETF Attendees Reengineer Their Hotel's Wi-Fi Net

alphadogg writes "What happens when a bunch of IETF super nerds show up in Paris for a major conference and discover their hotel's Wi-Fi network has imploded? They give it an Extreme Wi-Fi Makeover. Members of the Internet Engineering Task Force, who gathered for the outfit's 83rd meeting this week in France, discovered as they arrived at the Hotel Concorde Lafayette that the Wi-Fi was flakey and became flakier still as scores more attendees arrived and tried to connect, and the wired net was having issues of its own. Working behind the scenes, a team of IETF attendees negotiated with the hotel and were granted access to the wireless network, and began rigging up all sorts of fixes, which even included taping a Nexus S phone to a ceiling and turning off the radios on numerous access points to reduce noise."

Re:the phone

[AntmanGX]

"There was no WiFi signal when on the desk in front of the window in my room, but after some experiments, I discovered that the signal was quite good... on the ceiling of the bathroom," emailed Marc Petit-Huguenin.

"I have a Nexus S phone, so I taped it on the ceiling of the bathroom, and used tethering over Bluetooth to bridge the gap to the desk," he explained. This is a slow connection, but good enough to send emails over SMTP or use vi [the popular Unix text editor] over SSH."

FTA

I have been in hotels with a cable co wifi modem

[Anonymous Coward]

I have been in hotels with a cable co wifi modem in the room (good as I needed to reboot it aka unplug and replug to get it working)

Re:the phone

[SailorSpork]

In other words, it was a short fix so he could get initial wireless access to the network from his own computer so that they could get in an poke around some more. They did not deploy smartphones around the whole hotel as a permanent solution. I think the whole Smartphone thing was played up to make the article seem more appealing, but after he did that it looks like they used more mundane, standard approaches to tune and adjust the network to get it running to spec.

Re:Jury Rigged WiFi

[robot256]

I don't know if what they did qualifies as jury-rigged. They basically mapped out the entire network and assigned RF channels and power levels so that adjacent floors would not interfere with each other. Seems like whoever installed it before just threw up an access point in every other room and left it on full power. What the IETF guys are doing is certainly not totally optimized yet but it's a big improvement over what was there before.

Re: Nexus S phone???

[DroolTwist]

Or.. maybe you could RTFA. The summaries are to give enough information to let you decide if you are interested in reading the article. If the summary is going to cover every single detail, they may as well just paste the entire article in the summary section, and do away with the links.

Re:Wheres the Beef??

[Anonymous Psychopath]

You know those 802.11 wireless standards implemented in just about every wireless network device in the world? These guys wrote them. Literally. Rest assured they understand what they're doing.

You have a point about future support, but characterizing them as just a bunch of guys with badges who barely have a clue makes you seem ignorant.

Re:Lower power

[Anonymous Coward]

"It's a 2.4Ghz infrastructure in a highly 3D and rather radio transparent environment -- where the three non-overlapping channels [all that are possible in that band] are a real problem."

They're in Paris. There are four non-overlapping channels in Europe: 1, 5, 9 and 13. While it is customary to use 1, 6 and 11, especially in settings where international visitors are expected, if the network really needs 4 channels, they are available and should be used.

The proper way to fix the Wifi in multi-story buildings is with directional antennas, to reduce the 3D problem to multiple 2D problems.

Re:Lower power

[chefmonkey]

And that's ultimately what Chris did: we're now operating on four channels. Well, six, actually -- some of the APs could operate in the 5 GHz spectrum, so rather than leaving them off, they were re-purposed for the equipment that could use them (which offloads all the Macs and iPads from the 2.4 GHz spectrum, bringing the noise floor down). So now, running down one side of the building, we have 1, 5, 9 and 13; and then on the other side, 13, 9, 5, and 1. The APs on the tips of the building (it's shaped like an American football in horizontal cross-section) are on the 5GHz channels 40 and 44. The pattern is reversed for every other floor, to provide as much vertical spacing as possible.

This should help you visualize the layout: http://www.ietf.org/proceedings/83/slides/slides-83-iesg-11-ietf-operations-and-administration-plenary.pdf [ietf.org]

Keep in mind also that the APs, when we showed up, were turned up all the way up. Look at the diagrams, and keep in mind that these are small rooms (the building is maybe 150 feet wide along its longer axis), and you begin to see how the deployment failure was pretty complete before we got here.

Of course, we didn't show up with 300 directional antennas to fix the APs themselves. All we could do is change their configuration. The change has been dramatic.

Re:the phone

[Short Circuit]

There were too many active radios, and the spectrum was too crowded. They even switched to a four-channel layout instead of the three-channel. (We informally use a five-channel model in my apartment building, what with all the various tennants' APs and routers finding the least crowded piece of spectrum in their immediate area.