When The Wifi Blows: Experience At NAB 2011

The past week or so my attention was wholly consumed by the annual convention of the National Association of Broadcasters. Held in Las Vegas each April the NAB exhibition is the major event in the year of a broadcast equipment maker. This was my 18th NAB, which makes the more a test of stamina than anything else.

Happily, the show was for my employer a considerable success. Attendance has returned to reasonable levels. It seems that broadcasters are feeling better about their existence. Globally broadcasters are starting to move forward with long stalled projects. New channels will be launched and existing services enhanced. It all bodes well for the manufacturing sector of the industry, presuming that manufacturers have toughed out the recent slow period and continued to develop products that improve the operating efficiency of customers.

For our company the one major annoyance of NAB 2011 was the complete failure of wifi on the show floor. From the last day of setup to the close of the event wifi was essentially useless. This was not a huge problem, but a considerable inconvenience. In our case it meant that the many sales and executive staff present could only access email via a wired network connection.

Like every other company on the show floor we pay a pretty penny to Smart City for our internet connection. Long the brunt of our disdain, they have ramped up their game in recent years. They now deliver a reasonable service for a wholly unreasonable price. That’s about as much as you can expect from someplace like the Las Vegas Convention Center.

Our booth network was once based upon a cheesy little Linksys router and some kind of switch. More recently we’ve been modeling it after our US offices, using m0n0wall on a Soekris SBC to route access, and a couple of 24 port gigabit switches as the core. The decision to use m0n0wall was based on its ability to provide QoS and traffic shaping in support of VoIP.

Network connectivity has become an increasingly important aspect of our evolving product offering. Where once we sold freestanding devices that could operate without a network connection, now many of our products are multi-chassis systems that require network connectivity to achieve their stated functionality.

The booth also includes a Gigaset S675IP SIP/DECT cordless phone system. This device registers with our OnSIP account, making the booth an easily accessible extension on our US phone system. In past years passing SIP through Smart City has been hit or miss, but this year it was absolutely perfect.

Key staff in the UK have been issued Gigasets for their homes, which means that staff at NAB enjoyed HDVoice (G.722) calling to the development team during their time in Las Vegas. Most of the company is aware of what they think of as merely “Michael’s voip affliction.” This time around a few, including our CTO, made a point of saying how great the calls to the dev team sounded this year. It was an improvement directly attributable to that very affectation.

Wifi is added to the stand largely as an afterthought, using a now elderly Netgear WG-602 802.11 b/g access point. It worked well enough during the week before the show when all of the manufacturers were building their stands. But from the opening day it was useless. While a PC might connect to the wifi it could not actually get internet access. The RF environment in the hall was simply too congested.

The venue itself provides a wifi network that attendees can access for a fee. I could see Cisco commercial access points scattered around the building in support of that service. The larger problem was that many of the hundreds of exhibitors, like ourselves, were using their own private wifi as well. A few individuals even had hotspot type devices on the floor. There were simply too many wifi access points sharing the same physical space. It was RF chaos.

Firing up  a freeware wifi analyzer tool on my Android cell phone I could find no less than 27 access points advertising their presence. There are only 13 channels in the 2.4 GHz wifi band, and of these it’s only possible to use three without the overlap causing some kind of interference.

When I could not get access by means of the booth AP I tried to tether to my cell phone, but that failed as well. With 20+ APs within reach the wifi clients simply could not get decent connections to their designated targets.

I wasn’t the only one trying to gain wifi access from my cell phone. Several of our UK based staff now carry the HTC Desire Z, which is the same phone as my T-Mobile G2. The Desire Z has the HTC Sense GUI whereas the G2 is a “pure Google experience.” Those carrying the Desire Z or iPhone also run Counterpath’s Bria as a means of connecting to our company PBX. This works ok when the wifi is solid, but was entirely unworkable during the show.

AFAIK, almost all of the wifi on the show floor was 802.11b/g in the 2.4 GHz band. The venue’s wifi was dual-band, but the 5 GHz radios were only used to backhaul the traffic from all the clients on the 2.4 GHz band.

While I have not been specifically tasked with finding a solution to this problem I’ve been doing a little reading about the issue. Small Net Builder has a nice reference piece on wifi interference.

I’m left wondering if perhaps we should try to leverage the less congested 5 GHz band. Since few of our clients are 5 GHz capable that would mean deploying a handful of dual-band USB wifi interfaces for use with laptops. That would leave only the smart phone users lacking for wifi access.

This is something that I will suggest to management as we move ahead. Perhaps we’ll have a new wifi strategy in place by the time that the European IBC exhibition rolls around in September.

I’ll close this little tale with one final observation. This was the first exhibition I can recall where we made literally no use of Skype. In years past there’s be a utility PC in the back room where staff could go to make Skype calls to associates and family back in the UK. With the continuing penetration of SIP into the company, and the ability to leverage HDVoice based calling, everyone in Vegas used SIP this year. I consider this a minor win for my long running battle to see open, standards-based voip deployed company-wide.