A year after its acquisition of BelAir Networks, Swedish mobile equipment giant Ericsson has fully integrated its high-powered outdoor Wi-Fi technology into its wireless networks. Ericsson’s first commercial small cells will come with BelAir’s technology embedded, letting mobile operators build high-capacity cellular and Wi-Fi networks side by side, Ericsson CEO Hans Vestberg told GigaOM in an interview.
You can think of small cells as Wi-Fi access points that use dedicated mobile spectrum: Just like Wi-Fi access points, they’re short-range wireless nodes designed to pack a lot of bandwidth into a limited area. But unlike Wi-Fi, small cells link to devices directly through their cellular radios.
By putting combo small-cell/Wi-Fi nodes up in heavily trafficked areas both indoors and out, would give mobile networks a capacity double bonus. The cellular aspect would allow networks to handle many more device connections and provide faster speeds over those connections, while Wi-Fi could be used to offload bulk traffic — such as streaming video and file downloads — that would normally congest cellular systems.
Vestberg said with a few exceptions Wi-Fi would become pretty much a standard feature in its small cells gear, starting when the first networks emerge in the fourth quarter, Vestberg said. Not all carriers will use the capability, but Ericsson hopes to seed future networks with nodes that can easily support the technology. Depending on the configuration, carriers might be able to upgrade to Wi-Fi by slotting a board into their small cell chassis. In some cases that upgrade might even be as simple as sending a software patch over the network.
Cramming Wi-Fi into a small cell really isn’t that difficult. In fact, BelAir had already tackled the reverse of that problem when Ericsson bought it last year. BelAir builds big outdoor metro-Wi-Fi networks (AT&T is among its customers), and in 2011 it started embedding small cells into Wi-Fi access points in field trials.
Ericsson, however, is doing something a bit more complex than just putting Wi-Fi and cellular radios in the same housing. It’s integrating Wi-Fi directly into the cellular network, eliminating the problems that invariable result when moving between the two networks today.
Ericsson’s system will be able to manage “handover from macro to micro, micro to Wi-Fi and back to micro or macro all over again,” Vestberg said. This is what Ericsson and other vendors often refer to as the heterogeneous network, or HetNet. Instead of just shunting all Wi-Fi traffic onto the closest broadband connection to the internet, HetNets will manage Wi-Fi just like cellular nodes.
Why is that important? Uninterrupted access for one — that video stream won’t die when your device moves off cellular and try to negotiate a Wi-Fi connection. The network can also use Wi-Fi more intelligently. It can keep more secure communications on the cellular network, while routing bulk data to Wi-Fi. Since the network knows the relative data loads on both Wi-Fi and cellular nodes, it can make better decisions on which network to place a subscriber – there’s no point in shifting a customer onto an overloaded access point if the cellular network has capacity to spare. Also, if you’re driving in a car through the HetNet, it won’t connect you to Wi-Fi nodes, or even small cells, since the it knows you’d be out of range a second later.
These are definitely much more elegant solutions than the Wi-Fi offload we have today. Right now our phones try to connect whenever they detect an authorized Wi-Fi AP — even if it has no internet connection or is overloaded with other users. The HetNet, however, would be able to take advantage of Wi-Fi’s enormous capacity benefits without the hiccups.