The Cisco VNI Global Mobile Data Traffic Forecast methodology includes a combination of direct data collection from more than 1.3 million users and nearly two dozen service providers around the globe, in-house estimates and forecasts, and third-party analyst projections from organizations such as Informa Telecoms and Media, Strategy Analytics, Infonetics, Ovum, Gartner, IDC, Dell'Oro, Synergy, ACG Research, Nielsen, comScore, Arbitron Mobile, Maravedis and the International Telecommunications Union (ITU).
The Cisco VNI methodology begins with the number and growth of connections and devices, applies adoption rates for applications, and then multiplies the application's user base by Cisco's estimated minutes of use and KB per minute for that application. The methodology has evolved to link assumptions more closely with fundamental factors, to use data sources unique to Cisco, and to provide a high degree of application, segment, geographic, and device specificity. We use a variety of inputs, from data used by more than 1.3 Million people using our Cisco VNI apps to third party subscription growth forecasts to analysis of broadband trends occurring within the networks of nearly two dozen service providers around the globe.
Cisco has consistently revised VNI predictions publicly to reflect new data and trends. For example, in February 2010 we did not have a tablet breakout. By 2011, after the iPad was introduced the previous Spring, we updated the forecast to include this new device which would dramatically change the mobile landscape.
As reported in the published in the Mobile VNI Whitepaper, the recent mobile traffic growth forecast was adjusted for several reasons, including the fact that mobile laptop traffic growth is slowing, particularly in Western Europe. As people replace mobile laptops, which consume more bandwidth than most other devices, we will see variances in growth.
In addition, Service Provider Wi-Fi has increased far faster over the past year than our forecast in 2011. It is a "top of mind" issue for mobile service providers worldwide, many of which are actively deploying Wi-Fi solutions or looking to do so soon. While complementary to the macro-radio based Mobile Internet, we account for Wi-Fi in our fixed traffic forecast, which will be released in June. If we were to include offloaded traffic with mobile traffic, the difference between last year's forecast and this year's is much narrower. Also, people are using Wi-Fi small cells more often, shifting more data from mobile networks.
We have consistently used what we believe to be the most accurate currently available data to support our methodology in updating the forecast each year, rather than artificially imposing consistency with previous estimates.
Here's the link to the complete VNI Mobile whitepaper: