It's WiFi - But is it Carrier Class?

Nov. 19, 2014
The predictions on the fast growth of WiFi have largely come true, and the cable industry is very much in the middle of the action. Many of the ...
The predictions on the fast growth of WiFi have largely come true, and the cable industry is very much in the middle of the action.

Many of the same organizations that correctly predicted what has happened until now have a collective view of the future. Their opinion can be summed up pretty simply: You ain’t seen nothin’ yet.

In recent weeks, Mobile Experts predicted that service providers will deploy more than 4 million hotspots and 20 million “homespots” next year. iGR said carrier hotspots in North American will reach $44 million by 2018. ABI research said carrier WiFi revenues will reach almost $8 billion by 2019. Infonetics said the equipment market will hit $3 billion by 2018.

Any way you slice it, that’s a lot of WiFi. Success, however, is qualitative as well as quantitative. The experts say there is work to be done before the industry can call its WiFi initiatives “carrier class.”

Ken Roulier, Amdocs’ (NASDAQ:DOX) CTO for broadband, cable and satellite, said the cable industry’s WiFi initiatives have been impressive. The forward thinking must be on what must be in place once systems are deployed. The score on that front, he said, is mixed. “I would say there are multiple areas where they’ve done things intelligently and others in which it could be done perhaps a little better,” he said. “It’s not the rollout per se, but the management once it’s rolled out.”

The era of best effort WiFi must come to an end. Subscribers will expect a lot and, if operators don’t deliver it, competitors will. In general, the phrase "carrier grade WiFi" refers to a WiFi setup that provides enough throughput for the subscriber to perform any task that is possible with a wired Ethernet connection. In addition, there must be feedback loops and other ways of maintaining quality of service and quality of experience (QoS and QoE) and ways to boil through the noise to catch problems before they disrupt services. Analytics must be available for network administrators to keep on top of how the system is performing and to plan for necessary changes.

The planning necessary to move the industry’s WiFi initiatives to carrier class must take place on a couple of levels. Primarily, WiFi is liable to interference and doesn’t consistently permeate structures and other obstacles. This is well known, of course. But the step up to carrier-class status simply means that operators confront these issues in a manner that is systematic, repeatable and capable of guaranteeing a certain level of service.

The most important element is to know the customer. Portable test gear and back office tools capable of performing and utilizing the input from site surveys is emerging. “It’s important to do all the pre-work and planning,” said Steve Harris, the senior director of advanced network technology for the SCTE. “The site survey is key, and is one of the most important steps you can take.”

It is important to remember that a site survey done for 802.11n or 802.11g is does not mean that the AP placement is appropriate for 802.11ac. This is particularly true in that 802.11ac operates exclusively in the 5 GHz range. In addition to the changes within the 80.211ac specification, there have been more general changes in WiFi technology - such as multiple in multiple out (MIMO) and beam forming antennas - that figure to make old site surveys obsolete.

In addition, each iteration of 802.11 is backward compatible to what came before. 802.11ac deployments must play nicely alongside 802.11n and 802.11g infrastructure, which still are common in older homes and businesses.

Another feature of 802.11ac that can cause confusion is channel bonding that can make 80 MHz of bandwidth available to a single user. It is a feature that should be used prudently. “If it is one AP in a network and there is not a lot of WiFi interference in the the area, the operator may want a high bit rate for video, for instance, and in that case, 80 MHz channels makes sense,” said John Anderson, the product planner for wireless networks at Fluke Networks. “If there are 50 APs in a 50,000-square-foot office building, if they deploy 80-meg channels, there is a lot of overlap, so there likely would be co-channel interference. So in most of those channels perhaps should on be at 20 MHz.”

The size of the channels used in a given instance is one example of the complexities of WiFi deployments. Achieving carrier class status means having a plan to deal dealing with these and assorted other issues before problems arise.