CloudStor is a web service provided by AARNet to allow users to exchange large files securely with other AARNet users. The service can also be used to exchange files with "external" users. The service is primarily meant to solve the problem of transferring large files, such as data collected in research projects, or data stored in bandwidth-hungry multimedia formats, where it is not possible to do so via email or FTP. UQ users can access the service using their UQ login credentials. This is made possible through the Australian Access Federation of which UQ is a member.

CloudStor is not intended to be a web hosting platform. Any file transferred via CloudStor will be deleted after 20 days. File size is limited to a maximum of 100GB, and the maximum number of recipients for a file is 100.