CTOs of Mobile Network Operators need to make a choice. Do they want to spend their cap-ex on building Carrier Wi-Fi networks, or should they spend it on LTE small cells that are capable of combining both licensed and unlicensed spectrum to support growing Enterprise demands? We've just released a White Paper that explores these options and considers the alternatives.
"Outside-In" has its limits
Until recently, most options for in-building cellular systems haven’t been commercially attractive for the medium sized enterprise. Technical solutions have either been too costly or simply unavailable. Network operators haven’t been interested or engaged in offering a solution, focusing instead on an “outside in” strategy. However the latest Enterprise small cell products satisfy the viable price point and we are seeing some operators beginning to embrace this opportunity. Vodafone UK report their LTE can now achieve nearly 60% deep indoor coverage in London, partly by equipping over 400 buildings with dedicated in-building systems.
Meanwhile Wi-Fi technology continues to evolve rapidly in both technical capability and ease of use. High-speed 802.11ac can achieve over 100Mbps data rates. Wi-Fi Calling integrates seamlessly into the same user interface/dialer in the latest smartphones. Passpoint enables fast, secure and seamless authentication to network operator deployed and managed access points.
Both technologies are targeting greater use of the unlicensed 5GHz band with a variety of network architectures to increase capacity and throughput.
There are several industry initiatives proposing closer interworking and integration of cellular/ Wi-Fi which share the unlicensed 5GHz spectrum. In our latest white paper, we consider and evaluate how each of these various industry initiatives is best suited to address those needs for the Enterprise sector.
Exclusively licensed, exclusively unlicensed or the best of both?
Surely every smartphone today can make use of Wi-Fi, albeit perhaps not up to the very latest standard. But many can’t transmit over both cellular and Wi-Fi simultaneously. In future, we can expect to see combined use of both licenced and unlicenced bands to provide an overflow or boost data channel when higher bandwidth is needed. The 3GPP standards body is actively working towards two separate methods that would make this more seamless:
- LWA (LTE Wi-Fi Aggregation) which adds data to an LTE session using standard Wi-Fi data channels. Data traffic may be routed via the eNodeB with a proportion forwarded through a nearby Wi-Fi access point.
- LAA, which adds one or more 5 GHz unlicensed channels as supplementary downlink to an LTE channel in licensed spectrum using LTE Carrier Aggregation. It is expected that a mechanism such as “Listen Before Talk” will be included for compatibility with Wi-Fi sharing the same band, and this is likely to have some performance impact compared with native LTE.
It is uncertain which of these will become a dominant standard. In the short term, today’s investment in Wi-Fi or cellular in-building systems would not preclude later adoption of either.
A compelling case for Enterprise Wi-Fi
There has been a strong business case to invest and install Enterprise in-building Wi-Fi systems. Staff laptops and smartphones can be connected in meeting rooms and hot desks without the need for cabling. Cellular data usage is considerably reduced, saving mobile phone bills. Full mobility (seamless handover when moving around the building) isn’t expected. Costs and staffing are generally fixed and known in advance, making it easier to budget for. Size and complexity of these installations has led to a need for increased expertise and technical knowledge to design and maintain these systems.
However, Enterprise Wi-Fi is designed for a completely different usage and does not support network operator needs for an indoor system dedicated to their subscribers. Upgrading or migrating such systems to a fully independent Carrier Wi-Fi system open to all-comers is unlikely.
In their search for additional spectrum, network operators will need to make a clear choice between investing in their own Carrier Wi-Fi and adopting LTE-U/LAA. When combined with small cells, either option could carry substantial amounts of additional data traffic.
Wi-Fi appears to have the advantage by already being deployed in many buildings and most smartphones. By far the majority is for private or business use, restricted to individuals or businesses. Many public venues rely on interaction with and knowledge of users, preventing the seamless access and full mobility that cellular users enjoy.
LTE-U/LAA looks attractive to some network operators because it has little or no impact on their core network and back office systems – it operates as just another LTE frequency band. Data traffic served would inherently be chargeable whereas Wi-Fi is perceived to be free by many end users. It also provides differentiation because it is tied to an individual network operator.
In the short term, investment through in-building small cells brings immediate benefits without the need for new smartphones or spectrum. The various standards being developed will capitalise on that, protecting the investment and ensuring solutions exist to meet longer term capacity demands. Network operator CTOs need to be making a clear choice and set a direction for the future.
Meanwhile, Enterprise CTOs are likely to continue to pursue their own parallel Wi-Fi to meet their own business needs. Their interest will be to ensure that nothing interferes or disrupts it. That does not preclude deployment of small cells provided that the associated Carrier Wi-Fi or LAA complements rather than conflicts with it.
For a more in-depth analysis, read our latest report “Unlicensed Spectrum in the Enterprise” (no registration required to download).
This white paper was sponsored by SpiderCloud with content developed and written by ThinkSmallCell.