Implementation of file fault tolerance is the key to preventing data loss in cloud

especially the off-site disaster recovery

which can prevent large-scale power outage and natural disaster occurs from losing data.Currently disaster recovery guarantees for multi-cloud-based storage service provider agreement.To solve these problems

we propose a remote disaster recovery capability for cloud data to validate the programDPBDL

whose theory is to use time delay and the proofs of retrievability to check the off-site data recovery of cloud data.Then

we analysis its security and performance theoretically and practically

and the analysis result shows that its security and be able to accurately determine the cloud data off-site disaster recovery capabilities.