Storms in Mobile Networks

TL;DR

This paper analyzes signalling storms in mobile networks caused by overloads in the control plane, using mathematical and simulation models to understand their impact and propose mitigation strategies.

Contribution

It introduces a mathematical model and detailed simulations to analyze the effects of signalling storms and suggests ways to detect and mitigate them in 3G and 4G networks.

Findings

Signalling storms can cause significant control and user plane disruptions.

Mathematical models can predict congestion caused by attacks.

Proper system parameter tuning can mitigate storm effects.

Abstract

Mobile networks are vulnerable to signalling attacks and storms that are caused by traffic patterns that overload the control plane, and differ from distributed denial of service (DDoS) attacks in the Internet since they directly attack the control plane, and also reserve wireless bandwidth without actually using it. Such attacks can result from malware and mobile botnets, as well as from poorly designed applications, and can cause service outages in 3G and 4G networks which have been experienced by mobile operators. Since the radio resource control (RRC) protocol in 3G and 4G networks is particularly susceptible to such attacks, we analyze their effect with a mathematical model that helps to predict the congestion that is caused by an attack. A detailed simulation model of a mobile network is used to better understand the temporal dynamics of user behavior and signalling in the network and to show how RRC based signalling attacks and storms cause significant problems in the control plane and the user plane of the network. Our analysis also serves to identify how storms can be detected, and to propose how system parameters can be chosen to mitigate their effect.