Abstract:
Over recent years cloud computing has attained foremost commercial success. Cloud computing
minimizes resource wastage risk by reducing the entrance barrier for cloud service providers. By
extensive usage of cloud services unstructured data volume is increasing exponentially.
Therefore security considerations to save data from hackers are top risks to adapt cloud
environment. To avoid illicit use of unstructured data placed on the cloud different encryption
techniques and standards have been proposed by the researchers. Data searching becomes a
challenging task by adopting the existing searchable encryption techniques. In this paper a new
technique Position Based Sentence Search (PBSS) has been proposed. This technique facilitates
user with sentence searching on encrypted unstructured data in cloud environment. PBSS
provides an efficient ranked sentence search by means of preprocessed indexes. Documents are
ranked by two ranking parametersStandard Deviation (SD) and Term Frequency (TF). There is
no need of decrypting documents during the search process as in existing techniques. Decryption
is done on the retrieval of the documents by user. Cloud server or malicious users have no
knowledge ofdocuments content placed on the cloud therefore PBSS achieves security and
privacy
