Fuente: Wipo "BigData" The present disclosure discloses methods and systems for storing data in a distributed data storage system (213). The method includes receiving (302) unencrypted data from a client node (202) for storing at a server node (208). The received data is split (304) into one or more data chunks (228) of various sizes. Further, each data chunk is encrypted (306) using a key based on content of corresponding data chunk, and each encrypted chunk is stored (308) at a memory of a server node (208) using a unique data reference. Furthermore, an index chunk (230) is formed (310) that contains one or more data references of one or more encrypted chunks in a predefined order, along with one or more corresponding encryption keys of one or more encrypted chunks, which after being encrypted and stored, the corresponding data reference of this encrypted index chunk is provided (312) to the client node.