Abstract: Granary is a public storage service on the Internet that has two distinguished goals compared with previous projects. First, it is object-oriented, and thereby supports attribute-level data query. Second, it is very flexible to the system environment, i.e., it can be deployed in a grid-like environment, a peer-to-peer-like environment, or even a compromised one. Presented in this paper are Granary's architecture as well as some of its significant components that are designed in adherence to these two goals, including the node-collection protocol PeerWindow, the routing infrastructure Tourist, and the object-index management algorithm PB-link Tree. An implementation of Granary has been developed and will be deployed in China Grid.