The world of wireless communications changed, quietly, about two years ago. That was when the WiFi Alliance announced that it was issuing a draft of the 802.11n wireless standard that device makers could use until the final standard was released in 2009. Well, 2009 came and the standard was ratified (in September). 11n Wi-Fi is real.
So why is this a seemingly non-event? Because the draft standard worked and because the standard has been adopted in piecemeal fashion.
Now that the standard has been ratified, what does it have to offer organizations that are still a Wi-Fi generation behind? And is 802.11n an all-or-nothing deal?
While 802.11n is a lot faster than previous standards-it will transmit data at speeds of up to 160M bps over short distances-it offers other improvements, as well. These include a better method of encoding packets, making delivery more reliable; support for QOS (quality of service); and support for MIMO (multiple input, multiple output), which allows the radios in wireless devices to use multiple antennas to improve reception. Last but certainly not least, 802.11n devices operate on both the 5GHz and 2.4GHz bands.
Analysts say 802.11n should trump all other Wi-Fi iterations.
“802.11n is the only technology that matters,” said Craig Mathias, principal at Farpoint Group. “If you’re going to buy wireless technology, then buy 11n. We’re there now, and there’s no reason to wait.”
Mathias said that because 11n-based new devices are compatible with previous versions of Wi-Fi, there’s no risk-everything will just work better as portions of your network move to 802.11n.
In reality, though, there’s a lot more to 802.11n Wi-Fi than just compatibility.
“The thing that makes 11n so compelling, besides the performance profile, is the explosion of dual-band support,” said Kelly Davis-Felner, marketing director for the WiFi Alliance. “It’s very easy to have a network where you have people segregated on 5GHz and 2.4GHz. You get similar performance out of both frequency bands, and a lot of products work on both.”
In addition to working on two frequency bands, 802.11n supports QOS tagging, which means that data requiring priority, such as audio and video, works a lot better in an 802.11n environment. This leads to, for example, the ability to deliver high-definition television over Wi-Fi-something that was never really feasible before.
But in the real world of most enterprises, streaming HDTV is probably not a major consideration for moving to the new standard. Instead, it’s lower operational costs, higher reliability and easier management. “A lot of vendors will tell you about video,” Mathias noted. “I don’t think anyone is buying it exclusively for video.”
Instead, you have more capacity and more control, according to Davis-Felner. “All the things that you’ve heard in terms of capacity, range and throughput are true-11n is truly an Ethernet replacement. There isn’t a reason why you’d want to go to a wired alternative.”
Making the Move
Making the Move
While a move to the newly ratified 802.11n standard certainly makes sense, what’s less clear is how to accomplish it.
In some cases, network managers are simply replacing old Wi-Fi access points with 802.11n APs, putting the new devices in the same place and with the same network infrastructure as the old.
Felner-Davis said that this probably isn’t the best approach.
“From a network planning standpoint, the properties are different,” Davis-Felner explained. “You can’t just take down an 11g [AP] and put in an 11n [AP] and expect the same coverage. 11n responds completely differently to obstacles. It uses multipath to augment the signal. Most of the time, you’ll get better coverage [with 11n], so you could end up over-deploying.”
Davis-Felner said that this doesn’t mean you have to replace your wireless network all at once. “You can do it piecemeal, but you should do it more mindfully. Most companies are adding 11n when they expand the network,” she said.
Analyst Jack Gold of J. Gold Associates said the most effective approach to 802.11n migration is to start with a survey. “You really want to do an RF [radio frequency] survey,” Gold said. “N does perform a bit differently. Just dropping [802.11n APs] in where you had the old access points can work, but it’s not optimal.”
Gold said that the RF survey is necessary because most enterprise 802.11n access points work on both the 2.4GHz band used by most Wi-Fi today and the 5GHz band used by 802.11a. He said that the two frequencies react differently to obstructions such as walls.
The obstruction issue led Kimpton Hotels and Resorts to begin a migration to 11n in its guest networks.
“For us, one of the primary advantages of n is the better signal propagation,” said Donald O’Grady, director of technology for Kimpton. “We renovate a lot of historic properties, and 11n gives us a lot better signal propagation. We weren’t really getting it for the extra bandwidth. But the signal propagation was an important feature for us. Now, we’re leveraging the better bandwidth as well.”
Kimpton is using the newly realized bandwidth to deliver television signals to guest rooms, among other applications. O’Grady said the hotel and resort organization is using 802.11n gear from Ruckus to provide guest rooms with Wi-Fi access, and is leveraging the same infrastructure at its Philadelphia Palomar property to provide high-definition video.
O’Grady said he has plans to add other 802.11n-based equipment in guest rooms, including door locks and minibars. He noted that the cost savings are substantial. “Every cable we don’t install in a guest room saves $60,000 on a new building.”
O’Grady added that he’s already seeing a return on his 802.11n investment in the form of higher guest satisfaction scores in hotels with 11n. “This year we’re up to 87 percent extremely satisfied,” he said.
The Farpoint Group’s Mathias noted that such multimission networks are the wave of the future for 802.11n. “VOIP, data, video, data collection, security, sensors, RFID-all that kind of stuff we’re going to see using Wi-Fi,” Mathias said.
He added that the growth of 802.11n is also likely to spur the growth of cell phones with built-in Wi-Fi. “Mobile device management is an area of concern,” said Mathias. “Once we get the personal device on the network, we can manage it on the network.”
Mathias said that T-Mobile is currently the only provider producing cell phones that also offer voice service over Wi-Fi, but thinks the other carriers will have to follow suit. “T-Mobile has been way ahead of the curve,” he said. “The cellular carriers need Wi-Fi. They can’t survive without it. They don’t have enough licensed bandwidth for those services they want to sell.”
Mathias noted an additional benefit to carriers: “It gives them an ability to lock in the enterprise.”
While video is frequently noted as an 802.11n driver, neither Mathias nor Gold sees a rapid move to video in the enterprise. “There already is some adoption,” Mathias said. “The question is when it becomes common, but it’s not in 2010. Video will be a relatively small percentage of overall traffic.”
“I think for most enterprises, video isn’t going to be that big of a draw,” Gold added. “For most enterprises, it’s things like VOIP or file sharing and IM.”
Video aside, 802.11n is a standard that is well worth embracing.
“People will be very glad they have 11n in the out years,” Mathias said.
In the meantime, he noted, even a mix of Wi-Fi gear will benefit from 802.11n: “It’s a better g than g.”
Contributing Analyst Wayne Rash can be reached at wrash@eweek.com.