45 research outputs found
Your Privilege Gives Your Privacy Away: An Analysis of a Home Security Camera Service
Once considered a luxury, Home Security Cameras
(HSCs) are now commonplace and constitute a growing part
of the wider online video ecosystem. This paper argues that
their expanding coverage and close integration with daily life
may result in not only unique behavioral patterns, but also
key privacy concerns. This motivates us to perform a detailed
measurement study of a major HSC provider, covering 15.4M
streams and 211K users. Our study takes two perspectives:
(i) we explore the per-user behaviour, identifying core clusters of
users; and (ii) we build on this analysis to extract and predict
privacy-compromising insight. Key observations include a highly
asymmetrical traffic distribution, distinct usage patterns, wasted
resources and fixed viewing locations. Furthermore, we identify
three privacy risks and explore them in detail. We find that paid
users are more likely to be exposed to attacks due to their heavier
usage patterns. We conclude by proposing simple mitigations that
can alleviate these risk
On Uploading Behavior and Optimizations of a Mobile Live Streaming Service
Mobile Live Streaming (MLS) services are now one of the most popular types of mobile apps. They involve a (often amateur) user broadcasting content to a potentially large online audience via unreliable networks (e.g., LTE). Although prior work has focused on viewer-side behavior, it is equally important to study and improve broadcaster operations. Using detailed logs obtained from a major MLS provider, we first conduct an in-depth measurement study of uploading behavior. Our key findings include large wasteful uploads, strong viewing locality, and traffic dominance of loyal viewers. Specifically, 33.3% of uploads go unwatched, and the viewership of broadcasters tends to be localized to a small set of broadcaster-specific network regions. Inspired by our findings, we propose two system innovations to streamline MLS systems: adaptive uploading and edge server pre-fetching. These optimizations leverage machine learning for reduced waste and improved QoE. Trace-driven experiments show that the adaptive uploading reduces the resources wastage by 63%, and the pre-fetching boosts the startup by 29.5%. © 2022 IEEE
Muses: Enabling Lightweight Learning-Based Congestion Control for Mobile Devices
Various congestion control (CC) algorithms have been designed to target specific scenarios. To automate this process, researchers have begun to use machine learning to automatically control the congestion window. These, however, often rely on heavyweight learning models (e.g., neural networks). This can make them unsuitable for resource-constrained mobile devices. On the other hand, lightweight models (e.g., decision trees) are often incapable of reflecting the complexity of diverse mobile wireless environments. To address this, we present Muses, a learning-based approach for generating lightweight congestion control algorithms. Muses relies on imitation learning to train a universal (heavy) LSTM model, which is then used to extract (lightweight) decision tree models that are each targeted at an individual environment. Muses then dynamically selects the most appropriate decision tree on a per-flow basis. We show that Muses can generate high throughput policies across a diverse set of environments, and it is sufficiently light to operate on mobile devices. © 2022 IEEE
