Remote-control caching: Proxy-based url rewriting to decrease mobile browsing bandwidth

Mobile browsers suffer from unnecessary cache misses. The same binary object is often named by multiple URLs which correspond to different cache keys. Furthermore, servers frequently mark objects as uncacheable, even though the objects' content is stable over time. In this paper, we quantify the excess network traffic that mobile devices generate due to inefficient caching logic. We demonstrate that mobile page loads suffer from more redundant transfers than reported by prior studies which focused on desktop page loads. We then propose a new scheme, called Remote-Control Caching (RC2), in which web proxies (owned by mobile carriers or device manufacturers) track the aliasing relationships between the objects that a client has fetched, and the URLs that were used to fetch those objects. Leveraging knowledge of those aliases, a proxy dynamically rewrites the URLs inside of pages, allowing the client's local browser cache to satisfy a larger fraction of requests. Using a concrete implementation of RC2, we show that, for two loads of a page separated by 8 hours, RC2 reduces bandwidth consumption by a median of 52%. As a result, mobile browsers can save a median of 469 KB per warm-cache page load.