Traffic analysis and rollback

We do not address the issue of traffic analysis in this paper; that is, we do not make any explicit attempt to obfuscate users' access patterns. However, Plutus does support options to encrypt filenames, and encrypts all I/O requests to the server. Recently SUNDR [32] introduced the notion of a rollback attack, wherein an untrusted server tricks a user into accepting version-wise inconsistent or stale data relative to other users. We defer the discussion of rollback protection to a future work [15].