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Wi-Fi: It’s the other cell network

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Japan’s KDDI has seen the future of cellular service, and Wi-Fi has a starring role. The mobile operator will build out a Wi-Fi network composed of 100,000 hot spots and a WiMAX overlay that will take traffic off the cellular network when needed and will integrate seamlessly with the carrier’s existing 4G network. Given the demand for data, this heterogeneous network is the future of mobile broadband, and could lead to lower operating costs and perhaps cheaper prices for end users.

Here’s how KDDI’s network will operate according to Ruckus Wireless, the company providing the Wi-Fi base stations:

Lightning-fast hotspot deployment and cheap wireless backhaul

    The base stations are all dual-band 802.11n boxes with Ruckus’ adaptive antenna in them. The access points have a special USB port on the back that KDDI uses to connect a WiMAX router for backhaul.

Cover your insides

    Contrary to conventional wisdom, the majority of mobile data traffic that needs to be offloaded (some 75 percent) is generated indoors where cell signals have trouble and where users are most of the time.

Seamless sign on

    KDDI developed a special software client that uses existing cellular credentials. There’s a one-time “activation” process that requires the subscriber to use the cellular network to download a small client that then automatically configures all the encryption keys, wireless SSID and authentication information on the end device.

Adapt the existing Wi-Fi to something carrier grade

    KDDI isn’t using a traditional hot spot. Though they provide Wi-Fi access to KDDI users, the base stations are mobile data offload sites designed to siphon data traffic off the cellular network and onto a parallel Wi-Fi network that’s tied into their overall network architecture so KDDI is able to maintain visibility and control over the subscribers.

What KDDI has done is take the jerry-rigged AT&T (s t) or Verizon (s vz) approach to Wi-Fi, whereby a mobile operator provides access to free hot-spots but relies on the user to do the work, and tossed it out the window. KDDI has brought Wi-Fi (and WiMAX) into its network and made it work together in a way that will proactively keep its cellular network less congested. It also helps answer my question — why isn’t Wi-Fi better? — from a few months ago. Presumably, KDDI has or will also implement rules that will help route traffic onto the most appropriate network based on the content, cost and existing network traffic. It also needs to get a client that works on phones other than those running Android (s goog).

Consumers like Wi-Fi already.

However, such intelligent, multi-mode networks are the inevitable future for mobile operators given that our current demand for data will surpass our available spectrum. This has big implications for carriers, who could lower their cost for transferring a bit over their network by using alternative technologies, and perhaps lower the costs for consumers (or reduce caps.) It also changes the stakes for device makers who may have to start thinking about more power efficient radios (Wi-Fi is a notorious battery suck) and for Wi-Fi equipment providers such as Ruckus, Bel Air Networks, Meraki and Tropos. My guess is those carrier-grade Wi-Fi providers will suddenly find themselves acquisition targets from the Ericssons (s eric) and Alcatel-Lucents (s alu) of the world.

So, keep an eye on KDDI, its 32 million subscribers and its build out, which will be completed by March 2012. The future of mobile networks is less than a year away.

14 Responses to “Wi-Fi: It’s the other cell network”

  1. Regarding roaming from one hotspot to another. The question you have to ask yourself is why do you need it? What applications require a user to seamlessly roam from hotspot to hotspot. Is it really a problem if a user re-up’s his network credentials while roaming. The anwser lies with the application.

    Regarding cell phones without voice, the itouch does this via skype.

  2. better adams

    I paid $32.67 for a XBOX 360 and my mom got a 17 inch Toshiba laptop for $94.83 being delivered to our house tomorrow by FedEX. I will never again pay expensive retail prices at stores. I even sold a 46 inch HDTV to my boss for $650 and it only cost me $52.78 to get. Here is the website we using to get all this stuff,

  3. It would be interesting to know why KDDI did not opt for the standard WPA security mechanism (using EAP-SIM/AKA for authentication directly against the SIM card). Did they give any reason for “rolling their own”?

    Operators mounting Wi-Fi APs is an interesting development, but what would really be a game changer is if property owners and businesses would let operators use their already installed Wi-Fi APs for mobile offload (with compensation of course). With a simple AP side software upgrade multiple operators could use the spare capacity of a corporate WLAN to offload mobile data, securely and with a seamless user experience (operator branded EAP-SIM/AKA authenticated virtual Wi-Fi network). I’m working on one such solution ( but there are many ways to do it each with its pros and cons.

    • Marat

      Japanese usually opt for their own way of doing things. Besides, KDDI doesn’t provide SIM cards since their network is CDMA.

      And have you heard of FON?

      • Good explanation. :) But my general feeling is still “if you need an app to make it usable you’re not doing it right”.

        Yes, FON is definitely one of those solutions with its own pros and cons. Our thinking is that by taking away the cons we can get more operators on board, the most important of those being manual sign-in, many security issues and complex co-branding. Ours is a white-label solution with end-to-end encryption, all the way from the device to the home operators network, and standard WPA authentication.

  4. Per-Ola

    I would not really agree that AT&T’s WiFi network is “jerry-rigged”, but instead a pretty seamless working way for us users (especially on the iOS devices) to get ubiquitous high-speed access w/o eating up our 3G data plans. Handovers would be fine, but since most data usage is “static”, i.e not moving around, connection to one (well functioning) WiFi AP does the trick. Why make it more complex if it does not have to?
    Personally, I have never had any issues with AT&T’s WiFi.

    • Gv 3f

      Your statement presupposses that all Amrricans are like you.
      Basically you live in a zone full of retail using att wifi,you probably have cable or dsl for the house another wifi internet line for the office and
      are in a densely packed area or “box” full of signal. You do realize you are doing more work to support your device than the work it does for you.
      Try using wifi while going across the country on business using Amtrak or even the hiway.
      Try using wifi if you live 5 miles from town in a rural area where your choices for wired lines is nonexistent.
      You are not free to move about the country. You must follow defined paths of cell, spotty retail wifi and personal internet connections.
      Not all Americans want to live as a boob in a box.

  5. N8nNC

    If KDDI can do this in Japan (though the coverage wasn’t described), why can’t Apple do it in the US? Disintermediate the carriers that don’t get it (and none I’ve seen do). Then once a critical mass has wireless broadband at home, disintermediate the cable companies. It’s coming, whether by WiFi/WiMax or LTE-Advanced.

    • There is a dramatic difference in coverage required between the US and Japan. It is imply not practical or possible to implement such a combo system everywhere in the US.

      Even if the effort is focused just in major cities, the density of WiFi spots required (since the range is so small) would be cost-prohibitive – all the Muni WiFi efforts in the US (with one Google-sponsored exception) have failed for that simple reason. Point is cell-tower range is measured in miles/kilometers and WiFi range is measured in feet/meters.