AppSachet: Distributed App Delivery from the Edge Cloud

With total app installs touching 100 Billion in 2015, the increasing number of active devices that support apps are posed to result in 200 billion downloads by 2017. Data center based App stores offering users convenient app access, however, cause congestion in the last mile of the Internet, despite use of content delivery networks (CDNs) or ISP-based caching. This paper explores the new paradigm of eBoxes, situated in the ‘edge cloud’ tier beyond the last mile, which can be used to alleviate this congestion. With redesigned app caches – termed AppSachet – such edge cloud based distributed caching can achieve a hit ratio of up to 83 %, demonstrated on real-world Internet traffic. The redesign leverages proposed new caching policies, termed p-LRU and c-LRU, specifically targeted at eBoxes’ limited storage and for the traffic caused by app installs and updates. A cost benefit analysis shows that the additional cost required to deploy AppSachet on eBoxes can be recovered within the first three months of operation.