Abstract: Methods and systems of encrypting files at a client in a cloud-based file system are provided. A first key corresponding to an organization to which the client belongs is obtained. Then a first file is encrypted using the first key. Then the encrypted first file is transmitted to a server via a secure channel, for storage in a storage device shared among multiple organizations, the storage device containing one or more files encrypted using keys different than the first key.

Abstract: A copy of a first file may be stored in a first instance of a file space associated with a user of a first client device. An event is generated for a first modification of the first file and the event is sent to a server. A current revision number of the file space is obtained from the server, and the current revision number is compared to a past revision number corresponding to a last time files were synchronized to the first client device. In response to a determination that the current revision number is higher than the past revision number, a number of events that have occurred to the file space are requested from the server, the number of events corresponding to a difference between the current revision number and the past revision number. The first instance of the file space is updated based on the events.