Although organised by the WBA, the scope of this event is much wider than just Wi-Fi Roaming (perhaps too much so) and discussed many aspects of Carrier Wi-Fi. Growing membership of the WBA was also reflected in a higher turnout. Very lively debate on LAA, good networking and market update made this a worthwhile event to attend.
Tower Bridge outside the conference venue – Can the industry bridge the gap between Carrier Wi-Fi and Cellular?
Limited public progress with Carrier Wi-Fi Roaming
With many Carrier Wi-Fi networks and modern smartphones fully compatible with Passpoint and Next Generation Hotspot, I had expected to hear of many more roaming agreements and interoperability by now. The WBA tracker chart shown below indicates some large countries but relatively little takeup in Europe. Shrikant Shenwai, WBA CEO, sees quite a lot of momentum, lots of carriers have deployed Passpoint enabled equipment but you may not hear public “big bang” announcements. They announced 22 new members at the event including many new small technology companies. The WBA continues to update its tests each time a new release of Passpoint becomes available. Their Interoperability Compliance Program provides a checklist to determine Wi-Fi network roaming capabilities.
Perhaps one reason for the slow takeup is the lack of a roaming hub, as found between GSM operators. I understand that roaming today is primarily through direct peer-to-peer arrangements. Accuris and BGS seem to be the main technology providers, with Accuris announcing a partnership with TSS for billing so they can be a one-stop shop for Wi-Fi roaming. One vendor told me that compared to GSM roaming using clear 3GPP specs and sharing the same “playbook”, the Wi-Fi industry is more like the Wild West with a huge range of variances and special cases. Clearly the WBA is trying to bring some order to the chaos, but it’s still relatively early days. The WBA publishes a tracker of roaming agreements shown below.
The Largest Test case for Passpoint?
The one to watch will be Sprint and Boingo, where about 40 million of Sprint’s 56 million customers have handsets which are capable of using the Passpoint service for data, which Sprint call “Wi-Fi Auto Authentication”, and is available free of charge. Some 12-14 Million Sprint iPhone users will be automatically enabled to use these Boingo hotspots overnight using Passpoint in the next iOS update, including Wi-Fi Calling (VoWiFi). The exact date will be determined by Apple but likely late Q3 2015. When any of those Sprint iPhones sees a Boingo hotspot, it will seamlessly use it for voice and data. The 35 major airport sites include Detroit and LAX.
Derek Peterson, CTO Boingo, told me his team have been running around and testing all their airport installations with Voice over Wi-Fi calling to ensure it works well. He’s confident they’ve solved it, and can walk through Detroit airport (the one with the indoor transit train) from end-to-end across 24 Access Point handoffs without dropping a call. They’re using 5GHz rather than 2.4GHz for Passpoint, giving them 24 to 28 channels and have learnt a lot about how best to support voice. “First we designed our Wi-Fi networks for capacity using 802.11ac. Now we are designing for mobility. We’ve come across some bugs with 802.11k and 802.11r, where some access point products using both can interfere with each other. There are still a few bugs and issues to work through, so we’ve configured the system using alternative options until these are fully resolved”. Their next goal will be to sign up the MVNOs which run on top of Sprint, such as Virgin.
Another large Wi-Fi operator warned that the capacity for carrier grade voice service on Wi-Fi is quite limited. While a Carrier grade hotspot can handle anything up to 200 concurrent active users, it’s more like 4 to 10 active voice calls. This is because Wi-Fi is fully backward compatible and uses a 1 millisecond frame rate, making it inefficient to allocate many concurrent low latency streaming connections.
The other “gotcha” is handover between Wi-Fi and the cellular network which isn’t entirely reliable. Other US operators are concerned that calls may be dropped and don’t want to launch it until that’s reliable.
Hotels and venues opening up to Free Wi-Fi
While many network operators want to charge for their services, whether provided by Carrier Wi-Fi or cellular, many hotels and public venues offer it for free. Guoman Hotels, which runs many prestige venues in London (including the Tower Hotel hosting the conference) has a radical policy for a large hotel of free carrier grade Wi-Fi. It’s open to everyone, you just need to accept their T&Cs – no registration, user details or charges. Speed and performance are outstanding – they’ve tested up to 800Mbps and regularly achieve 400Mbps using 802.11ac. As a result, they are ranked #1 and #2 worldwide for Hotel Wi-Fi on TripAdvisor, leading to greater room occupancy and associated revenue. It’s quite costly to maintain (outsourced to BT), with hotel operational staff walking around every meeting room with test equipment to validate service quality daily. As Chris Hewertson their CTO said, you don’t expect to pay for heating or electricity in our hotels – so why Wi-Fi? It’s hammered their PayToView revenues with many guests watching streaming video for their own entertainment.
Heathrow Airport, another premium venue, also offers Free Wi-Fi (partly paid for by aircraft landing fees) but wants additional revenue to fund it. You have to register with personal details for a limited time usage. They can’t predict when it might become transparent and free, but thought it inevitable in the long term. AEG, a major stadium owner and operator, also thought the economics of free Carrier Grade Wi-Fi are more difficult – they really need to link in advertising and promotions to make their business case work. We are starting to see push advertising offering you a range of merchandise delivered to your seat – everything from food/drink to clothing – all ordered and paid using your mobile device.
LTE-U and LAA – A lively debate
In one of the most frank and lively panel debates I’ve seen for some time, Qualcomm faced heavy opposition to their proposals to run LTE in the unlicenced bands. Wi-Fi network operators want proof that it won’t detract from their carefully engineering and well behaved installations. CableLabs and TheCloud were especially vocal, turning down Qualcomm’s offer to see this demonstrated in their labs until Listen Before Talk had been agreed and implemented in 3GPP standards.
Keith Dyer documented the exchange verbatim
I’m chairing a panel session on the same topic at next month’s Small Cell World Summit and am looking forward to a similar lively debate, from a different perspective.
Network Virtualisation – Wi-Fi has had this for years
NFV (Network Function Virtualisation) is a hot topic in the cellular industry and Mark Grayson of Cisco has been leading a workstream with the Small Cell Forum (paper due out next month). He reminded me that Enterprise Wi-Fi had adopted virtualisation for some ten years, and that it was common to just “spin up a virtual controller” when you want to add further capacity. A major turning point was when Cisco acquired Airespace in 2005, moving away from purely autonomous independent access points for larger installations.
Ruckus Wireless re-inforced this position, launching their scalable SmartZone software product which co-ordinates anything up to 300,000 Wi-Fi devices in clusters of up to 30,000 Access Points. Software pricing starts at just $995 plus $100 per access point.
So what’s next for Wi-Fi?
Kelly Davis-Felner, VP Marketing Wi-Fi Alliance, felt the Wi-Fi industry needs to wake up and align/collaborate more with their cellular counterparts. They have very different cultures and progress on seamless roaming has been slow. She also highlighted some upcoming features in their work program.
802.11ac Wave 2 combines up to 160MHz of bandwidth to provide data rates up to 800Mbps. Multi User MIMO is already proven, with some proprietary early models shipping today [e.g. Ruckus]. Certification and vendor interoperability will come next year.
802.11ah uses the unlicensed band at 900MHz, going further but not at such high speeds. This rounds out the Wi-Fi portfolio and closes some of the gaps for the Internet of Things, supporting longer range and more devices per access point. It will compete with Zigbee and other specialist standards but be more capable and leverage the common base of Wi-Fi protocols. It’s still low power so not very wide area. Pre-standard 2016, certified mid 2017.
Wi-Gig (Wi-Fi at 60GHz) has gone quiet for various reasons, so the Wi-Fi Alliance aren’t (over)hyping it yet. It needs more members to actively contribute. 2017 is still feasible, probably first as a cable replacement technology.
Wi-Fi Aware, a proximity awareness feature in a super power efficient way, will allow people to find others in their neighbourhood and establish peer-to-peer connections. It should quietly roll out into silicon during the next 18-24 months.
Other activities in the Wi-Fi alliance include optimising the connectivity experience, faster link setup and generally making it work better when you are connected.
There are also some white space initiatives too, but when I mischievously asked if Wi-Fi would seek to operate in dormant/unused cellular frequencies, I understand that’s not on their agenda.
An interesting and worthwhile event, although not in the way I expected. Primarily about Carrier Wi-Fi rather than residential or best effort. Visible progress with Passpoint and roaming is still fairly limited, despite proof that the technology works. Top concerns for mobile operators remain whether their high customer experience can be maintained, with VoWiFi (Voice over Wi-Fi/Wi-Fi calling) remaining to be proven in high capacity venues. Seamless hand off to/from Wi-Fi also remains a concern. Nonetheless, the Sprint/Boingo deal will provide a major checkpoint during Q3 and I’m sure work continues on these other issues.
Several Wi-Fi proponents thought that Wi-Fi calling would heavily impact the opportunity for residential femtocells but did not forecast the immediate demise of either Enterprise Small Cells or DAS. Their focus is on in-building, especially the larger venues (hotels, stadiums, airports etc.) rather than outdoor.
I still see an opportunity for residential femtocells, although Wi-Fi calling will clearly impact that. While Carrier Grade Wi-Fi can deliver high performance (at a price), issues around voice quality, handoff and integration with the cellular network still remain to be resolved. There is still a place for Small Cells and DAS in the wider ecosystem.