The iPhone video threat: Can networks keep up?
- 22 April, 2008 08:38
Be careful what you wish for. The iPhone has realized the old promise of the mobile Web. But it's not clear whether the wireless networks can handle the load.
With news that Apple's little cell phone now accounts for more mobile Web traffic than any other device in the US -- and is No. 2 globally -- the issue of whether or not Web-enabled wireless devices will overwhelm cellular and Wi-Fi networks is about to come to a head.
Of course, it's not just the iPhone. Adding to the growing ways to access the Web over wireless is the new class of ultraportable PCs from the likes of PC stalwarts Lenovo and Hewlett-Packard and startups such as Oqo. Weighing in at four pounds or less, these devices are easy to carry around, and they offer displays that are far better than a two-inch screen.
The issue is not Web access, per se. Instead, it's access through the Internet to video and other multimedia content, which newer devices make such a simple and enjoyable experience.
Statistics from ComScore say that 9.1 billion videos were viewed online by July 2007. Last year, according to a New York Times article, video uploading and downloading from sites such as YouTube "consumed as much bandwidth as the entire Internet did in 2000." The trend is only expected to grow. In four years, according to MultiMedia Research Group, there will be 240 million video-enabled phones, as well as 63.6 million IPTV (Internet Protocol TV) subscribers by 2012.
Until recently, mobile Internet traffic has been mostly burst transmissions, such as e-mails, that can be more easily managed across the network without affecting the user experience. But video hogs the network for a good length of time, in the process squeezing out other traffic.
Most networks institute collision avoidance techniques so that various types of traffic don't get in each other's way, but that's harder to do with streaming media such as video. Typically, a local access point or cellular receiver will detect a video stream and make other traffic wait until the "gap" between video packets. Streaming media get priority because if there are too many gaps, the video or audio fragments. So other traffic such as Web pages and e-mails are forced to wait until the next available gap, likely leaving many users dissatisfied with the effective performance.
Organizations are cracking down
John Collins, the CIO at Prairie Cardiovascular, a Midwest health care company with 28 facilities, is already feeling the pain from the doctors coming into one of his facilities with their brand-new iPhones. Collins has faced numerous incidents of slowing networks and was forced to institute a policy that completely turned off wireless streaming video to its staff of doctors, nurses, and administrators. Collins also uses SurfControl from WebSense to block all shopping sites.
Prairie Cardiovascular's policies came about after the health care organization began experiencing serious problems with slow access over its Wi-Fi network. IT analyzed the system using a combination of Aruba Networks' built-in diagnostics, SurfControl, and features on its Nortel switch to identify and manage access, ultimately identifying shopping sites and video as the root cause.
"Most of these  facilities have VPN back to me. What would happen to the network if a doctor wants to stream a soccer match from India? I can't allow it. I need my EMR data and diagnostic imaging data going back and forth during the day," says Collins.
Nevertheless, after vociferous complaints from a number of physicians who wanted to do watch video streams over their handhelds, Collins relented just a bit and opened up the network for doctors' personal use for a half hour during the day and one hour at night.
Prudential Fox Roche, the third-largest US real estate firm, also had a problem with employees bringing in their wireless devices for video surfing, so it too tried to limit the use of video-oriented sites such as YouTube over its wireless network. "We do get overloaded with streaming," says William Friemann, the firm's vice president of technology operations, security, and compliance. Prudential offices typically have a single T1 line as the backbone for its wireless network, and a lone user can hog three-quarters of that with a video download. In fact, one employee was terminated for his refusal to stop streaming. "It was constant even after numerous warnings," Friemann said.
But Friemann says he can't shut down video streaming because Prudential also uses streaming for e-learning; the marketing department uses the technology extensively as well.
With tight budgets, Prudential won't increase bandwidth to satisfy YouTube users. "We are just not going to buy additional bandwidth," Friemann notes.
Handset trade-offs are a key culprit
But the real problems have only just begun, according to Aruba Networks CTO Merwyn Andrade. Andrade points out that while high-performing 802.11a and 802.11n networks might alleviate some congestion, for a number of practical reasons, Wi-Fi-enabled handsets will not be easily or quickly upgraded to these more capable Wi-Fi standards.
The 802.11b/g technology used in handhelds offers only three non-overlapping transmission channels (1, 6, and 11) for use with video. By comparison, 802.11a offers 20-plus channels. But handset vendors are trying to cut costs, and 802.11b/g chips cost less than 802.11a or 802.11n units. So handset makers use the lower-bandwidth technology.
Furthermore, the chips that work on the higher bandwidth consume more power, either requiring heavier, pricier batteries or shortening talk time. Vendors believe that users prefer more cell phone time between recharges over faster download times, says Andrade.
These cost and power reasons explain why it will be a long time before users see 802.11a or 802.11n Wi-Fi in cell phones, Andrade says. Thus, users and network managers may soon be stuck between the proverbial rock and a hard place. Because Wi-Fi is faster than cellular 2.5G technology such as the AT&T EDGE network that the iPhone uses -- "the 2.5G link on the iPhone sucks," says Andrade -- the Wi-Fi networks will soon be saturated with demand for video.
Time for new policies
Today, the new breed of Web- and video-capable mobile devices aren't generating enough traffic to hurt existing Wi-Fi and cellular networks, except in times of major disasters, says Gerry Purdy, chief analyst at Frost & Sullivan. "Current cellular capabilities are enough," he says.
When handsets become 4G-capable and, thus, can transmit hundreds of megabits per second, they will become a major issue, as users go beyond downloading videos and actually start creating videos on their mobile devices.
"Once you start using your phone as a camcorder and upload video to post to Facebook, there can be the potential for problems. A real-time video taking place in say Hong Kong by one person is OK, but if you have 10,000 people doing it, that's a lot of bandwidth," says Purdy.
To avoid nasty surprises later, Purdy says that IT has to start getting creative now in terms of making policies that haven't existed before: "Watch for policy development about rich media. An insurance adjustor taking a video will use a lot more bandwidth than a static picture, so companies need a policy about who can do what. It is all a balancing act."
Restrictive access policies may be a short-term solution to the problem. However, the long-term solution will more than likely be increased bandwidth capacity.
And although IT people may not gain a friendly ear as they try to convince a belt-tightening board that they need more bandwidth to accommodate employees using FaceBook and the like, paying for more capacity may become a necessity. "I would really have to justify spending on increased capacity," Friemann says.
Friemann and other IT executives may be able to do that once multimedia and video move from a consumer application to become part of a business solution.