Verifying a set of remotely stored data is disclosed, including: requesting a first element corresponding to a first leaf in a base layer of a digital tree, wherein the digital tree corresponds to a set of remotely stored data; receiving the first element corresponding to the first leaf; and receiving a membership proof comprising a set of elements from one or more layers higher in the digital tree than the base layer of the digital tree, wherein the set of elements comprises a path from the first leaf to a root of the digital tree, wherein the set of elements is dependent on a plurality of additional leaves and wherein verification of the first element corresponding to the first leaf increases a level of confidence in an availability of the plurality of additional leaves.