By Boris Bogatin
(This is a byline that’s been held over for nearly one and a half years, and what’s really surprising is that it’s become only more relevant since then. I urge the wireless industry to take note of the innovations available to fundamentally improve wireless networks and move to incorporate them at a pace that can match up to the pace of innovation brought about on a daily basis by the mobile Internet application ecosystem.)
Cisco recently estimated that the “demand for mobile data will double every year through 2014” and Marc Zuckerberg predicts that social sharing (including that of pictures and videos) will double every year indefinitely, creating at least 10x more data usage in just over 3 years and 100x in just under 7. In parallel, 4G service offers from wireless operators are just now making their way to the neighborhood storeshelfs, which bring about a much needed relief to the strained wireless networks, pumping in roughly 5-10x more capacity than available over 3G networks. So is that enough?
In sum, no. The 4G upgrades only take us to near-parity with the capability offered through WiFi points, which are powered by cable and DSL modem technologies of the 2000’s – they act more like band-aids and leave a huge gap in meeting consumers’ mobile needs of 2010’s. This gap is estimated at 3-5x in speeds and 20-100x in capacity, and one that’s projected to only widen over the next 5-7 years. Further, ultra-fast and high capacity WiFi is what’s driving consumers’ expectations for service quality and service experience when it comes to wireless broadband, since that’s what consumers are increasingly relying on to access the Internet from their tablets and smartphones – this leads to discrepancies in not just the level of service available in any given location but also in the types of services consumers can access using their WiFi networks and ones they can access using wireless operator networks.
In a world where Netflix and HD movies, peer-to-peer and group video calls, and exponentially rising social sharing are revolutionizing our day-to-day lives, the mobile Internet is and will continue to remain strained by the consumers’ insatiable and expanding appetites for mobile data. As wireless operators mull over solutions on how to make their way out of this Catch 22 situation, next-gen solutions that expand the wireless pipes without breaking the carriers’ business models are not a nice-to-have but are absolutely essential.
Luckily for all involved, the next generation of innovations are building on the 4G and WiFi breakthroughs of 2000’s, to bridge the mobile data gap of 2010’s. They include “distributed and het-net” wireless networking solutions which rely on bringing “wireless networks” physically closer to end users; working to open up the number of WiFi points a user can access and providing a much more seamless experience in accessing WiFi vs. carrier networks on the fly; and “optimizing networks” to speed-up wireless Internet through other means (techniques that resemble how Akamai and CDNs helped speed up the wireline Internet) and by offloading mobile data to other devices even beyond distributed and WiFi networks.
The Wireless Speed and Capacity Gap
With regard to wireless data speeds, 37% of consumers’ mobile surfing came through WiFi connections in August 2011 in U.S., which are typically powered by home broadband connections along the lines of Comcast and Time Warner’s Cable service or Verizon’s FiOS service, at speeds of 10-15 Mbps. In comparison, 63% of mobile data needs were served through wireless operator services, with the most advanced 4G offerings providing 2-8 Mbps on average today, and more commonly expected to provide 2-5 Mbps once adoption of 4G services picks up. Further, 4G offerings are just being rolled out now and 4G is widely considered as wireless technology of 2010’s. On other hand, Google and other providers are pushing 1 Gbps FTTH (fiber-to-the-home) service offerings, a technology slated to set the standard for home broadband of 2010’s and in turn power even faster WiFi connections (WiFi speeds can hypothetically range to north of 100 Mbps, but more commonly expected to top off at 50 Mbps or so). So today’s 3-5x discrepancy in wireless speeds between WiFi and wireless carriers is only going to widen over the coming 5-7 years, to reflect a gap much closer to 10-20x.
When we then look at the capacity of wireless networks, the equation is at an even greater disequilibrium. In New York City alone, the number of cell sites runs in the single digit thousands per carrier, with the total at roughly 10-20 thousand in total. With each site having a total of up to 45 Mbps in available capacity (constrained by the amount of spectrum and the number of 4G radios used and the backhaul available at each site), one can estimate that there’s a total of 30-60 thousand WiFi-point-equivalents in wireless capacity in NYC. In contrast, there’re millions of WiFi points in NYC (given that there are 20 million people with a large portion owning own WiFi points, and hundreds of thousands of business, enterprise offices, and public WiFi points in the region). Given that on a per-capita basis, there is relatively even less wireless network capacity than there is WiFi capacity in other U.S. markets, the capacity supplied through WiFi points today is roughly 20-100x greater than that supplied through 4G wireless networks, and will only widen with the FTTH advancements mentioned above.
How We Ended Up Where We Are
Wireless networks are designed in a way that’s not entirely dissimilar to how we think of WiFi. They use wireless towers (the ones you see on the sides of the roads, sometimes in form of fake-looking pine trees) instead of WiFi routers, to connect with mobile users’ devices, and then use fiber connections, instead of Cable and FiOS offerings, to route the mobile data traffic from the towers throughout the Internet. But each wireless tower has a number of associated costs, from the cost of setting it up and installing it, to the cost of operating it day to day. So initially, wireless carriers deployed just enough towers to minimize their initial cost while offering coverage of the target markets and ensuring consumers with access to wireless service wherever they go.
But beyond providing adequate coverage, wireless networks rely on access to wireless spectrum to offer a certain level of data speeds and capacity, with the amount of spectrum available per tower as a key driver to the level of data speeds and data capacity a single tower can accommodate. Similar to how traditional wireline networks use wave division multiplexing (WDM) technologies to split up a given fiber cable strand to carry more and more traffic side-by-side, wireless carriers increase the capacity and speeds of wireless networks generally through one of 3 means – by increasing their access to wireless spectrum, by re-using that spectrum more efficiently (ie. 4G technologies), or by deploying more towers and create more use of the same wireless spectrum by splitting that use up geographically. So as traffic demands built up, carriers clamored for more spectrum and deployed technologies like 4G, and in parallel installed more and more towers to bring wireless networks closer to the users and to “re-use” their wireless spectrum in more places.
But installing more towers, in their traditional sense, has become cost prohibitive and physically impossible (in their current, “macro” or bulky configuration, they are mostly too densely situated now); 4G technology upgrades have largely maxed out the realm of possibilities for technology-driven improvements for boosting capacity; and additional spectrum has become almost impossible to come by.
Small Cell Networks and Het-Net Architectures
Enter small cell networks and het-net architectures, which call for distributing many WiFi-like wireless tower nodes into geographic areas where users are sucking down the most mobile Internet, and for using the “macro” cell networks to serve the remaining, overflow demand. The key component is a pico cell, which acts like a “micro tower” that sits on the side of a building or on a light pole or a traffic light, re-uses mobile wireless spectrum with neighboring pico cells, and overall costs only a small fraction of the cost it takes to install and operate a traditional “macro” wireless tower. And since these pico cells are located closer to users, much like WiFi routers, the capacity and speeds that they can achieve are actually much higher than those available from wireless towers which are further away. So at the end, this ends up creating not only more “nodes” for greater capacity, but also higher speed “nodes” scattered throughout a given area.
Well doesn’t this all come at a big price? There is a price, but it’s not as dramatic as it seems.
First, mobile spectrum (spectrum below 3 GHz) although incredibly scarce and expensive to come by, can actually be “re-used” a very large number of times in a given geography when used for small cell networks (hundreds of thousands to millions of times in the case of the NYC example – just like WiFi spectrum), which creates much more additional capacity (10-100x) using almost the same amount of total spectrum. Further, small cell nodes are configured to be manufactured at much lower costs and can use sides of buildings, light poles, and other much lower cost real-estate resources. Lastly, unlike wireless towers that use fiber connections to route mobile traffic to the Internet, pico cells rely on using a different type of wireless spectrum, microwave wireless spectrum, to “relay” mobile traffic to nearby “macro” sites and “fiber nodes” which in-turn have extensive fiber connections hooked in. Microwave wireless spectrum includes spectrum like that owned by IDT Spectrum at 38 GHz, is not well suited for serving users directly but is very effective in wirelessly connecting “pico” cells and other outdoor small cells, and is available in very large quantities (there’s 10x more of it available than mobile spectrum) and at 1/100th to 1/1000th of the price of mobile spectrum. This means that using microwave wireless spectrum to carry the mobile Internet traffic from small cells to “fiber nodes” is much more cost-effective than having to have a fiber connection installed to each of the small cells individually.
Overall, small cell networks make available a much larger number of wireless nodes in the form of pico cells and bring them much closer to mobile users. But unlike a traditional wireless network, pico cells cost only a fraction of the cost, can use microwave wireless spectrum to carry the pico cell traffic from small cells to the fiber networks avoiding most of the fiber operating costs, and overall can be operated at very low operating costs. A small cell network using 10x more pico cells than there are wireless towers in a given area, can multiply wireless capacity by more than 10x, all at a cost that’s about equivalent to the cost of a macro cellular network. With major wireless vendors including Ericsson, Alcatel-Lucent, and others already lining up with high quality pico cell solutions, small cell networks should be a critical source of the mobile data capacity needed over the 2010 decade.
Wireless Internet Hot Spots and “Network Offloading”
In Times Square, free WiFi has been installed to offload the burden off of mobile towers. Large corporations like McDonalds and Starbucks offer free WiFi at their branches, making WiFi more accessible to smartphone users in places they already frequent. AT&T and Verizon have also expanded their WiFi footprints and have gone so far as to create collaborative WiFi efforts through the WiFi Interoperability Group. And consumers and businesses’ are increasingly using their WiFi as much as possible, intentionally offloading wireless data use to their WiFi networks. Increasingly, programs that build on these trends, aim to package WiFi access into a seamless extension of wireless networks, to help offload the mobile data traffic surge to WiFi networks whenever possible.
In many cases, WiFi hotspots function much like small cell networks to serve high mobile traffic zones – they just use WiFi technology and WiFi spectrum instead of that used by pico cells. But unlike small cell networks, WiFi hotspots are not built to effectively carry mobile voice traffic (although are effective for serving mobile data which of course is the very reason for the mobile data capacity crunch). They also use unlicensed spectrum that tends to become somewhat more congested in high traffic areas – all the WiFi signals in a given area have to compete with one another for access to unlicensed spectrum allocated to WiFi. And WiFi networks are often closed off to most users, because they are either configured for private use by their consumer or business owners or require different subscriptions at each different WiFi point. But WiFi hotspots are much more ubiquitously installed today and can overall be used reasonably ubiquitously to offload a great deal of wireless data traffic – what’s required is strictly a more seamless approach to tapping into those WiFi points by consumers, and an approach that provides all the WiFi owners with means to make money from use of those WiFi points by other users, to manage how much data traffic is offloaded onto a given WiFi point (so there’s not too much congestion), and a way to make WiFi access secure for all users (so that the users of WiFi points are not pre-disposed to security threats from one another).
Overall, WiFi hotspots have proven to be reasonably effective for “network offloading” mobile traffic, and their accessibility on a more open and seamless basis will play hand-in-hand with the benefits introduced by small cell networks.
Data Carpooling and Proximity-Powered Networks
Gone are the days where smartphone users have to rely on wireless networks or WiFi routers for 100% of their mobile data needs. A modern smartphone already has WiFi and Bluetooth built-in, and WiFi Direct is a new technology filtering into the market. These technologies can be used to make connections between devices directly (D2D networking), without using any wireless networks and at very high speeds (50-100 Mbps), albeit at even shorter distances than are used to reach pico cells or WiFi points (much like before, distance is a primary reason for the higher speeds). Unfortunately use of D2D connections has not really picked up over the past years as D2D has been largely too difficult to use and too unreliable – until now. Enter companies like Qualcomm and their AllJoyn technology – Qualcomm is doing the heavy-lifting required to tame D2D networking and provide access to D2D through straightforward APIs akin to ones used for IP networking and location-based services by many smartphone applications. Equally, companies like NearVerse integrate the use of D2D and wireless carrier networks in a unified system, optimizing the amount of data that can be offloaded from wireless carrier networks to D2D connections while also increasing the speeds of wireless services by optimizing how mobile data traffic is routed through D2D connections and wireless carrier networks. Overall, D2D technologies empower the sharing of mobile data content directly between users, essentially crowdsourcing D2D bandwidth that otherwise is left untapped, and help further mitigate the stress on wireless networks from the surge of mobile data traffic.
Concluding Words
Spectrum is a finite resource while 4G is not a silver bullet, and there is no magic solution for our current mobile data congestion issues. At the same time, there is a lot of opportunity in using distributed wireless networks to reduce data pileups in smarter and cost-effective ways. Innovations like VoIP, P2P networking, cloud computing, and content distribution networks are responsible for wireline Internet’s ability to support such wonders as video calling, Internet video watching, and rich social networking. We now have to tap into similar non-traditional areas of innovation to improve the capability of wireless networks, so that we can serve our exponentially rising mobile data appetites with the right levels of wireless capacity and at the right cost.
Boris Bogatin is the CEO and Founder of NearVerse, a provider of mobile network optimization technology and the makers of LoKast (www.lokast.com), a mobile cloud service for real-time interactive Spaces. For full disclosure, NearVerse has also partnered with Qualcomm on use of their AllJoyn technology, and Boris is also an advisor to IDT Spectrum, a significant holder of 38 GHz wireless spectrum.
