Philadelphia Eagles Join Stadium Wi-Fi Stampede

The Philadelphia Eagles' Lincoln Financial Field is the latest pro sports venue to get fan-facing Wi-Fi. Stadium Wi-Fi is trendy, but it’s not easy to pull off technically; I know because I designed the wireless network for my university's domed stadium. And do fans really benefit enough to justify the complex and costly implementation?

Sports teams are turning to wireless to help fill seats. As ticket prices rise, stadiums face increased competition from big-screen, hi-def consumer electronics that provide more options for comfortable game-watching at home.

Given that most stadiums do not allow laptops and tablets in the door to begin with, the de facto assumption in stadium wireless is that fans will be connecting from smartphones.

But that’s about the only assumption designers can make. Stadium wireless is a numbers game: How do you provide coverage for thousands of clients in a massive and unconventional building layout? How many of those clients do you expect to be on the WLAN simultaneously? And how much bandwidth do you attempt to allot to each device?

As a WLAN architect, I tried to get specific answers on the design aspects of the Eagles’ wireless deployment. I understand the sensitivities involved in not wanting to disclose too much to the general public (especially until the new system proves itself), but Enterasys -- which is providing the WLAN infrastructure -- provided enough information for me to gain some insight into the project.

At Lincoln Financial Field, the Eagles can seat 69,000 fans, who will be served by hundreds of APs that fully cover the stadium. For a stadium of that size, here's what a typical boilerplate approach to stadium design might be like.

Of the 69,000 seats, a typical system design will estimate some percentage of fans per event that will have devices they want to use at the venue, and then another fraction of this group that might be expected to be on the WLAN simultaneously. For conversation sake -- these are my numbers- not the Eagles’ -- we’ll say that 40% of the 69,000 fans are expected to use the WLAN, with an expected peak of three-quarters of WLAN users all on at any given time.

Boil that down and if the house is full, then around 27,600 devices would be expected per event with less than 21,000 actually on at any time. Though Enterasys says that the installed system provides excess capacity for “all the fans that want to utilize Wi-Fi,” it's a good bet that similar math went into the actual system design.

In my own experience, most fans go to the game to actually watch the game. Time spent on the WLAN usually amounts to a few quick Tweets or photos sent, checking email during breaks in the action, or catching up on scores from other games when the on-field action gets slow. This is why simultaneous devices can be hard to guestimate at design time, as few fans are actually glued to their mobile in the stands throughout the game.

From there, designers determine determine how many clients per AP can realistically be accommodated, and then how much bandwidth can be provided to round it all out. There is certainly more to the overall network design than this, but my hypothetical numbers should give you a sense of the general stadium WLAN-specific design approach.

[As you map out a 802.11ac strategy, make sure to plan for troubleshooting. Get tips in "802.11ac: Preparing To Troubleshoot."

I asked Enterasys how the Eagles would deal with rogue devices, such as MiFi devices (these tend to be perhaps the worst enemy of stadium WLAN), and was directed to Enterasys’ IdentiFi RADAR technology (think Cisco CleanAir). Monitoring spectrum for competing signals is one thing; sending folks into densely packed stands to ask John Q. Ticketholder to disable his personal hotspot that he didn’t even realize was on is altogether another issue. I wish Philly well on the task as that is the only way to mitigate low-power hotspots that can wreak havoc with stadium wireless.

On the network access front, the Eagles won't have a “splash page” portal; fans will just find the network and get on. This is good, because portals can get in the way of many apps when mobile devices make up your client base.

Speaking of apps, the Eagles already have a free mobile app,which doesn’t require connection to the stadium WLAN to use. The app is designed to complement the game experience for fans in the stadium, especially through the “stadium” module in the app’s menu, which provides facility maps, in-stadium video, a fan photo submission portal and other services. Only “club seat” holders can order concessions through the app, however..

Though stadium Wi-Fi is certainly a nice value-add, from the fan perspective it doesn’t usually rise to the level of being a critical service. At the same time, soon all pro stadiums (and a growing number of college venues) will have it, and we’ll see if a killer app emerges beyond ordering hot dogs or staring at small-screen replays while you miss the action on the field.

Learn about common problems that can affect WLAN performance, including troublesome client behaviors, IPv4/IPv6 issues and ISP problems in Lee Badman's session, When Users Think Your Good WLAN Is Bad at Interop in October.