Privacy Preserving Natural Language Processing in the Cloud Supporting Similarity Based Text Retrieval Through Blind Storage.

Abstract

Research in cloud computing is receiving a lot of attention from both academic and industrial worlds. In cloud computing, user can outsource their computation and storage to servers (also called clouds) using Internet. Clouds can provide serveral types of services like applications (e.g., Google Apps, Microsoft online), infrastuctures (e.g.,Amazon'sEC2,Euclyptus,Nimbus),and platforms to help developers write applications (e.g., Amazon's S3,Windows Azure).Much of the data stored in clouds is highly sensitive, for example, medical records and social networks. Security and privacy are thus very important issues in cloud computing. In one hand, the user should authenticate itself before initiating any transaction , and on the other hand, it must be ensured that the cloud does not tamper with the data that is outsourced. In order to search in cloud, some requirements is needed, search over In order to any transaction, and on the other hand, it must be ensured that the cloud does not tamper with the data that is outsourced. In order to search in cloud, some requirements is needed, search over encrypted data should support the following three functions. First, the searchable encryption schemes should support multi-keyword search, and provide the same user experience as searching in Google search with different keywords; single-keyword search is far from satisfactory by only returning very limited and inaccurate search results. Second, to quickly identify most relevant results, the search user would typically prefer cloud servers to sort the returned search results in a relevance-based order ranked by the relevance of the search request to the documents. our main contributions can be summarized as follows: