IJSRD - International Journal for Scientific Research & Development| Vol. 1, Issue 11, 2014 | ISSN (online): 2321-0613 All rights reserved by www.ijsrd.com 2408 Abstract--- Storage on cloud space is one of the impeach issues towards salvation of information. This challenging issue of security leads to development of different cryptographic methods. Cryptographic methods are designed to achieve system stability, data access, key management etc. One of the most excellent manners for depot of information on a storehouse like cloud is Attribute- based encryption (ABE). This thesis concentrates on combination of Cipher-policy attribute-based encryption (CP-ABE) and Attribute-based signature (ABS) yield assurance of unforgeability and secrecy for information swapping from cloud service provider (CSP) to subscriber. Information swapping to the CSP is done using CP-ABE encryption method. CP-ABE tool kit encrypts documents based on attributes of user. It includes master_key, public_key and private_key for individual users. Information can be decrypted by the users who possess the correct attributes. Hence, when subscriber requires information to be fetched from CSP, the CSP will apply ABS to validate information for correct subscriber. Keywords: Key policy based encryption, Cipher policy based encryption, Attribute based signature, Key generation, master_key I. INTRODUCTION To keep information private to data servers the information owner encrypts data before upload. User access is granted by possessing the information decryption key(s). When this kind of cryptographic-based access control scheme provide security protection on data, there are also several major challenges pertained to the scheme design [8]. To gain privacy of data from cloud service provider and other non- related nodes encryption techniques are key source that provides relevant security. Network security consists of number of methods to achieve cryptographic security. One of them is most popular method is Attribute-based encryption (ABE). ABE is recently invented one-to-many public-key cryptography, has the potential to enforce the fine grained access policies for large-scale systems [7]. ABE does not provide assurances towards the authenticity of the data. Attribute Based Signing (ABS) is an adaptation of Attribute Based Encryption (ABE) for the purposes of providing guarantees towards the provenance of the signed data, and moreover towards the anonymity of the signer. First section of this report describes ABE with its types Key-policy attribute-based encryption (KP-ABE) and, Cipher-policy attribute-based encryption (CP-ABE).Sub sections explains difference between two methods and encryption decryption specifications of each. It covers definition of attributes, how predicates help to gain privacy. Second section of this report explains Attribute-Based signatures (ABS) that allows signing a document with the set of attributes. ABS has variants like ring signatures, group signatures, mesh signatures that provide signatures from secret key authority. It covers behavior of signatures and method to apply signature to gain authenticity. II. ATTRIBUTE-BASED ENCRYPTION (ABE) Attribute-based encryption (ABE) is a cryptographic scheme that is targeted to achieve anonymous access control Attributed based encryption (ABE), first introduced by Sahai and Waters, provides a mechanism by which we can ensure that even if the storage is compromised, the loss of information will only be minimal. The basic concept was to encrypt the data before sending to the Cloud provider. But there is a problem still faced by the client. Because the Cloud provider needs to perform the calculations on data to respond the request from the client so he must provide the key to the server to decrypt the data before execute the calculations required, which might affect the confidentiality of data stored in the Cloud [1]. Mechanisms using data encryption, driven by policies, can be used to ensure degrees of (fine-grained) data protection, trusted third parties (called Trust Authorities (TAs)) can be used to provide compliance checking capabilities [2]. A user is able to decrypt the cipher text if and only if at least a threshold number of attributes overlap between the cipher text and user secret key. An access control policy would be a policy that defines the kind of users who would have permissions to read the documents. e.g. In an academic setting, grade-sheets of a class may be accessible only to a professor handling the course and some teaching assistants (TAs) of that course. We can express such a policy in terms of a predicate: ((Professor ^ CS dept.) V (M.tech student ^ course TA ^ CS dept.)) We will call the various credentials (or variables) of the predicate as attributes and the predicate itself which represents the access policy as the access-structure. In the example here the access structure is quite simple. But in reality, access policies may be quite complex and may involve a large number of attributes. A. Key-policy attribute-based encryption (KP-ABE) The idea of a KP-ABE scheme is as follows: the cipher text is associated with a set of attributes and each user secret key is embedded with an access structure which can be any monotonic tree-access structure. A user is able to decrypt a cipher text if and only if the cipher text attributes satisfy the access structure embedded in its secret key [8]. In Key Salvation of Information Exchange Over Cloud Service Provider by Predicate Based Algorithm and Finest Access Control by Attribute Based Signature Nihil R. Khagram 1 Asso. Prof. Narensingh S Yadav 2 1 M. tech Student, 2 Assoc. Professor, Head of Computer Science Engineering Department Sri Balaji College of Engineering & Technology – Jaipur, Rajasthan India