Abstract
Targeted advertising has transformed the marketing trend for any
business by creating new opportunities for advertisers to reach
prospective customers by delivering them personalised ads using an
infrastructure of a variety of intermediary entities and technologies.
The advertising and analytics companies collect, aggregate, process and
trade a rich amount of user’s personal data, which has prompted serious
privacy concerns among individuals and organisations. This article
presents a detailed survey of privacy risks including the information
flow between advertising platform and ad/analytics networks, the
profiling process, the advertising sources and criteria, the measurement
analysis of targeted advertising based on user’s interests and profiling
context and ads delivery process in both in-app and in-browser targeted
ads. We provide detailed discussion of challenges in preserving user
privacy that includes privacy threats posed by the advertising and
analytics companies, how private information is extracted and exchanged
among various advertising entities, privacy threats from third-party
tracking, re-identification of private information and associated
privacy risks, in addition to, overview data and tracking sharing
technologies. Following, we present various techniques for preserving
user privacy and a comprehensive analysis of various proposals founded
on those techniques and compare them based on the underlying
architectures, the privacy mechanisms and the deployment scenarios.
Finally we discuss some potential research challenges and open research
issues.