Secure and Efficient Outsourced k-Means Clustering using Fully Homomorphic Encryption With Ciphertext Packing Technique

Aim

         The main aim of this project is to preserve the outsourced data in cloud through gateway encryption, and to implement personalized search over the encrypted data in a secure way by NLP process without downloading and decrypting the entire group member file contents.         

 Abstract

           Research in cloud computing is receiving a lot of attention from both academic and industrial worlds. In cloud computing, users can outsource their computation and storage to servers (also called clouds) using Internet. Clouds can provide several types of services like applications (e.g., Google Apps, Microsoft online), infrastructures (e.g., Amazon’s EC2, Eucalyptus, 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 encrypted data should support the following three functions. First, the searchable encryption schemes should support 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.

 Existing system

         In existing system encryption of the documents are done in cloud server. All the files uploaded by the user are encrypted in cloud and stored in static memory locations. Hence keyword search is not possible on the encrypted cloud data. In order to make a search, the existing system downloads all the encrypted files and then decrypt for content based searching which is the traditional way to search. The situation could be even worse in the mobile environment due to the physical limitations of mobile devices, such as low bandwidth and limited storage capacity. In searchable symmetric encryption (SSE) and searchable public-key encryption (SPE), schemes, large number of documents, search results should be retrieved in an order of the relevancy with the searched keywords using TF-IDF method.

 Problem Definition

• Outsourced encrypted Data are directly stored in cloud, which may lead to severe confidentiality and privacy issues.
• Searchable encryption schemes fail to offer sufficient insights towards the construction of full functioned search over encrypted cloud data.
• Bulk content retrieval for file searching, which is inefficient.

 Proposed system

         In Proposed system, PSU (personalized search) scheme with efficient and secure updates we introduced an efficient and reliable methodology for search over encrypted data. Here the encrypted keyword search pre computes the resulting search documents for the input query from users through Natural language processing Technique which is implemented on gateway (client side) on user file upload. Hence the matching documents which is pre compute the before searching the encrypted cloud contents are retrieved from cloud. Here we does not pull all the encrypted data’s from cloud for searching, which is time consuming and ineffective. The matching documents memory locations on mobile storage are retrieved from the serializable objects which is stored in the gateway. User can download the resulting documents after getting the keys from the group owner. Asymmetric kind of encryption for key re-encryption and is more secured.

         User can upload the files in public and private mode. If user uploads files in public mode, the file is to encoded using Base64 algorithm. If user uploads in private mode the file content is encrypted using RSA algorithm and then can give access control for each group user. PSU proceeds in seven phases, System Setup, Building Encrypted Database, Trapdoor Generation, Search, Auditing, Decryption and, Efficient and Secure Updating.User search in cloud using keywords, cloud can send the related files to respective user. If data user wants to read the contents of files, data user should request to cloud and then cloud will request to data owner. Data owner checks the user attributes and access control, then the owner forward the private key and data’s in secure manner.