A Measurement Study of the Wuala On-line Storage Service
Wuala is a popular online backup and file sharing system that has been successfully operated for several years. Very little is known about the design and implementation of Wuala. The authors capture the network traffic exchanged between the machines participating in Wuala to reverse engineer the design and operation of Wuala. When Wuala was launched, it used a clever combination of centralized storage in data centers for long-term backup with peer-assisted file caching of frequently downloaded files. Large files are broken up into transmission blocks and additional transmission blocks are generated using a classical redundancy coding scheme.