Publication Details

Title: Beyond the Radio: Illuminating the Higher Layers of Mobile Networks
Author: N. Vallina-Rodriguez, S. Sundaresan, C. Kreibich, N. Weaver, and V. Paxson
Bibliographic Information: ICSI Technical Report TR-14-003
Date: December 2014
Research Area: Networking and Security
Type: Technical Reports

Cellular network performance is often viewed as primarily dominated by the radio technology. However, reality proves more complex: mobile operators deploy and configure their networks in different ways, and sometimes establish network sharing agreements with other mobile carriers. Moreover, regulators have encouraged newer operational models such as Mobile Virtual Network Operators (MVNOs) to promote competition. In this paper we draw upon data collected by the ICSI Netalyzr app for Android to develop a characterization of how operational decisions, such as network configurations, business models, and relationships between operators introduce diversity in service quality and affect user security and privacy. We delve in detail beyond the radio link and into network configuration and business relationships in six countries. We identify the widespread use of transparent middleboxes such as HTTP and DNS proxies, analyzing how they actively modify user traffic, compromise user privacy, and potentially undermine user security. In addition, we identify network sharing agreements between operators, highlighting the implications of roaming and characterizing the properties of MVNOs, including that a majority are simply rebranded versions of major operators. More broadly, our findings highlight the importance of considering higher-layer relationships when seeking to analyze mobile traffic in a sound fashion.

This work was partially supported by funding provided to ICSI through National Science Foundation grants CNS : 1111672 ("Measuring and Modeling the Dynamics of IPv4 Address Exhaustion"), CNS : 1213157 (“User-Centric Network Measurement”), and CNS : 1237265 ("Beyond Technical Security: Developing an Empirical Basis for Socio-Economic Perspectives") and by the DHS Directorate of Science and Technology under grant N66001-12-C-0128. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors or originators and do not necessarily reflect the views of the NSF or of the DHS. We also wish to thank Amazon, Comcast, and Google for their generous support.

Bibliographic Reference:
N. Vallina-Rodriguez, S. Sundaresan, C. Kreibich, N. Weaver, and V. Paxson. Beyond the Radio: Illuminating the Higher Layers of Mobile Networks. ICSI Technical Report TR-14-003, December 2014