Method for the distributed backup of a block B of digital data in a computer network comprising a distributed hash table DHT and at least three nodes NO , the nodes NO being connected to said network, said block B having an identifier, said method comprising a step of dividing said block B into r fragments F of digital data, an identifier being associated with each fragment F, said method being characterised in that it further comprises the following steps: - for each fragment F of the block B, a step of storing said fragment F in the memory resources of a node NO F ; - a step of recording the pairs (identifier of the block B, list of the nodes NO F ) and (node NO F , list of identifiers of the fragments F) in the parts of the DHT that are contained in at least two nodes ; such that no operation on the DHT or any storage operation is implemented on a centralised server - a step of recovering said block B comprising a first step of sending a request from the requesting node to the DHT, a second step in which the DHT returns thereto the nodes storing the fragments of the block on the basis of the pairs (identifier of the block B, list of the nodes NO F ), a step of sending a request for recovering fragments to these nodes , and a step of reconstructing the block B as soon as r different fragments have been received; - characterised in that it further comprises a step of periodically sending activity information from each of said nodes to a set of nodes selected by the DHT; - in that the DHT contains a "life cycle" field and in that the sending of said activity information updates the "life cycle" field of said node , said field being present in all of the nodes selected by the DHT, - in that it further comprises a step of detecting a "life cycle" field that is not updated by a node C failed ; and - a step of reconstructing the fragments F of blocks stored in said failed node C failed on the basis of the pair (node NO F , list of identifiers of the fragments F) and of updating, in the DHT, the list of the nodes storing at least one fragment of said block B . - for each fragment F of the block B, a step of storing said fragment F in the memory resources of a node NO F ; - a step of recording the pairs (identifier of the block B, list of the nodes NO F ) and (node NO F , list of identifiers of the fragments F) in the parts of the DHT that are contained in at least two nodes ; such that no operation on the DHT or any storage operation is implemented on a centralised server - a step of recovering said block B comprising a first step of sending a request from the requesting node to the DHT, a second step in which the DHT returns thereto the nodes storing the fragments of the block on the basis of the pairs (identifier of the block B, list of the nodes NO F ), a step of sending a request for recovering fragments to these nodes , and a step of reconstructing the block B as soon as r different fragments have been received; - characterised in that it further comprises a step of periodically sending activity information from each of said nodes to a set of nodes selected by the DHT; - in that the DHT contains a "life cycle" field and in that the sending of said activity information updates the "life cycle" field of said node , said field being present in all of the nodes selected by the DHT, - in that it further comprises a step of detecting a "life cycle" field that is not updated by a node C failed ; and - a step of reconstructing the fragments F of blocks stored in said failed node C failed on the basis of the pair (node NO F , list of identifiers of the fragments F) and of updating, in the DHT, the list of the nodes storing at least one fragment of said block B . <EOS>