Cell Spotting -- Studying the Role of Cellular Networks in the Internet

John P. Rula*†, Fabián E. Bustamante*, and Moritz Steiner†.
In Proc. of IMC, November 2017.
(*) Northwestern University (†) Akamai

Department of Computer Science
Northwestern University
Evanston, IL 60208, USA


The increasingly dominant role of the mobile Internet and its economic implications have been the topic of several stud- ies and surveys from industry and academia. Most previous work has focused on mobile devices, as a whole, independently of their connectivity, and taken the limited perspectives of either a few individual handsets or a single operator. We lack a comprehensive and global view of cellular net- works, their scope, configurations and usage.

In this paper, we present a comprehensive analysis of global cellular networks. We describe an approach to accurately identify cellular network IP addresses using the Network Information API, a non-standard Javascipt API in several mobile browsers, and show its effectiveness in a range cellular network configurations. We combine this approach with the vantage point of one of the world’s largest CDNs, with over 200,000 servers in 1,450 networks and clients in over 46,000 ASes across 245 countries, to characterize cellular access around the globe. We discover over 350 thousand /24 and 23 thousand /48 cellular IPv4 and IPv6 prefixes respectively. We find that the majority of cellular networks exist as mixed networks (i.e., networks that share both fixline and cellular devices), requiring prefix – not ASN – level identification. By utilizing addresses level traffic from the same CDN, we calculate the fraction of traffic coming from cellular addresses. Overall we find that cellular traffic comprises 16.2% of the CDN’s global traffic, and that cellular traffic ranges widely in importance between countries, from cap- turing nearly 96% of all traffic in Ghana to just 12.1% in France.