1. A cloud resource allocation server for adaptively striping data across a plurality of storage clouds, the cloud resource allocation server comprising: a communication module to receive (i) user constraints corresponding one or more cloud storage providers and (ii) a file to be striped across the one or more cloud storage providers; and a block allocation module to (i) split the received file into a plurality of file blocks and (ii) allocate each of the plurality of file blocks to a cloud storage provider of the one or more cloud storage providers as a function of the user constraints and operating conditions of each of the one or more cloud storage providers, each of the plurality of file blocks being allocated to a different cloud storage provider, wherein the communication module further to send each of the plurality of file blocks to the cloud storage provider to which each file block is allocated.