It's no secret that increased smartphone use over the past couple of years has put network operators in a difficult place in terms of handling all the data generated by those devices. Of course, solutions have emerged that help mitigate, namely small cells and carrier Wi-Fi.

Both of these help to ensure that mobile network data traffic keeps moving smoothly, particularly in crowded areas such as shopping malls and venues, but in different ways: Small cells add coverage and capacity within a small area, while carrier Wi-Fi converges Wi-Fi with mobile and cable networks to create heterogeneous networks (HetNets).

A recent report from Mobile Experts explains how carrier Wi-Fi will become more prevalent due to recent advances in Wi-Fi technology, particularly the new 802.11ac standard and 5GHz radios in handsets. According to Dr. Jacob Sharony, senior analyst at Mobile Experts, these technologies will see rapid adoption and "data will be offloaded quickly onto Wi-Fi, creating a need for new controller architectures and network integration software for interoperability with mobile networks."

In terms of network integration, the Wi-Fi Alliance's (News - Alert) new Hotspot 2.0 specification handles this by enabling devices to connect seamlessly to Wi-Fi from a mobile data connection. In fact, the report accounts for this in its roadmap of how the carrier Wi-Fi market will evolve.

Phase 0 will involve disjointed networks and very little connection between carrier Wi-Fi networks and mobile networks. Phase 1 will see Hotspot 2.0 and SIM authentication become standard, and Phase 2 will see refinement in terms of billing, policy control and interoperability of carrier Wi-Fi networks. Finally, phase 3 will be when advanced network intelligence optimizes the use of multiple air interface modes based on various factors.

While this may sound like carrier Wi-Fi is poised to crush the small cell market, it won't exactly play out like that, according to Joe Madden, principal analyst for Mobile Experts, who pointed out that many projects exist currently in which small cells and Wi-Fi are combined. Indeed, carrier Wi-Fi seems to be more of a supplement to small cells than anything else at this point.

It's hard to say how this will change within the next year or two, however as carrier Wi-Fi is advancing at a breakneck pace and Mobile Experts expects the market to hit $4 billion by 2018. Meanwhile, Infonetics Research puts the small cells market at $2.7 billion by 2017.