Friendstore
Dinh Nguyen Tran, Frank Chiang, Jinyang Li · 2008
Today, it is common for users to own more than tens of gigabytes of digital pictures, videos, experimental traces, etc. Although many users already back up such data on a cheap second disk, it is desirable to also seek off-site redundancies so that important data can survive threats such as natural disasters and operator mistakes. Commercial online backup service is expensive [1, 11]. An alternative solution is to use a peer-to-peer storage system. However, existing cooperative backup systems are plagued by two long-standing problems [3, 4, 9, 19, 27]: enforcing minimal availability from participating nodes, and ensuring that nodes storing others' backup data will not deny restore service in times of need.