Attribute-based encryption with verifiable outsourced decryption

Ministry of Education, Singapore under its Academic Research Funding Tier 1; Singapore Management University; Agency for Science, Technology and Research (A*STAR) SERC Gran

Blowfish Algorithm with Verifiable Outsourced using Cryptography

Cloud Computing is an emerging paradigm in our day to day world. As good as it is, this technique also bring forth many new trails for data security and access control when users outsource sensitive data for sharing on cloud.Attribute-based encryption (ABE) is a promising strategy for ?ne-grained access control of scrambled information in a distributed storage, nonetheless, unscrambling included in the ABEs is generally excessively costly for asset compelled front-end clients, which incredibly blocks it’s down to earth fame. Keeping in mind the end goal to decrease the decoding overhead for a client to recuperate the plaintext wereoutsourced most of the unscrambling work without uncovering really information or private keys. Here a novel technique is proposed to build an ABE with Veri?able outsourced decryption based on a blowfish encryption. It provides a unified model, which can be considered in both key-policy (KP) and cipher text-policy (CP) settings. In verifiability,it guarantees the correctness of the transformation done between the original cipher text and the simplified cipher text. A major issue is the absence of access control rights. So, it considered an access key structure for improving the security and performance by specifying access rights for the authorized user. Access control rights, restrictions and privileges for an individual are established. The access control rights is validated and results shows increased security level

PHOABE : securely outsourcing multi-authority attribute based encryption with policy hidden for cloud assisted IoT

Attribute based encryption (ABE) is an encrypted access control mechanism that ensures efficient data sharing among dynamic group of users. Nevertheless, this encryption technique presents two main drawbacks, namely high decryption cost and publicly shared access policies, thus leading to possible users’ privacy leakage. In this paper, we introduce PHOABE, a Policy-Hidden Outsourced ABE scheme. Our construction presents several advantages. First, it is a multi-attribute authority ABE scheme. Second, the expensive computations for the ABE decryption process is partially delegated to a Semi Trusted Cloud Server. Third, users’ privacy is protected thanks to a hidden access policy. Fourth, PHOABE is proven to be selectively secure, verifiable and policy privacy preserving under the random oracle model. Five, estimation of the processing overhead proves its feasibility in IoT constrained environments

CUPS : Secure Opportunistic Cloud of Things Framework based on Attribute Based Encryption Scheme Supporting Access Policy Update

The ever‐growing number of internet connected devices, coupled with the new computing trends, namely within emerging opportunistic networks, engenders several security concerns. Most of the exchanged data between the internet of things (IoT) devices are not adequately secured due to resource constraints on IoT devices. Attribute‐based encryption is a promising cryptographic mechanism suitable for distributed environments, providing flexible access control to encrypted data contents. However, it imposes high decryption costs, and does not support access policy update, for highly dynamic environments. This paper presents CUPS, an ABE‐based framework for opportunistic cloud of things applications, that securely outsources data decryption process to edge nodes in order to reduce the computation overhead on the user side. CUPS allows end‐users to offload most of the decryption overhead to an edge node and verify the correctness of the received partially decrypted data from the edge node. Moreover, CUPS provides the access policy update feature with neither involving a proxy‐server, nor re‐encrypting the enciphered data contents and re‐distributing the users' secret keys. The access policy update feature in CUPS does not affect the size of the message received by the end‐user, which reduces the bandwidth and the storage usage. Our comprehensive theoretical analysis proves that CUPS outperforms existing schemes in terms of functionality, communication and computation overheads

A Hybrid Verifiable and Delegated Cryptographic Model in Cloud Computing

التحكم بالوصول مهم جدا في تبادل البيانات السحابية. و خاصة في مجالات مثل الرعاية الصحية, فمن الضروري ان تكون هناك ألية لمراقبة قائمة الدخول من اجل السرية و الوصول الامن للبيانات. و قد تم التشفير القائم على السمة لسنوات عديدة لتأمين البيانات و توفير الوصول المراقب. في هذا البحث اقترحنا اطاراً يدعم آلية التشفير الدارة و السمة التي تتضمن اطرافا متعددة. هم مالك البيانات , مستخدم البيانات , خادم السحابة و سلطة السمة. ومن السمات الهامة للنظام المقترح هو التفويض الذي يمكن التحقق منه لعملية فك التشفير الى خادم السحابة. مالك البيانات يقوم بتشفير البيانات و مندوبين عملية فك التشفير الى السحابة. خادم السحابة يؤدي فك التشفير الجزئي و من ثم يتم مشاركة بيانات فك التشفير النهائي للمستخدمين وفقاً للامتيازات. مالك البيانات يقلل من التعقيد الحسابي من خلال تفويض خادم السحابة علمية فك التشفير. قمنا ببناء تطبيق النموذج الاولي باستخدام منصة مايكروسوفت دوت نت لأثبات هذا المفهوم. و أظهرت النتائج التجريبية أن هناك وصولا خاضعا للرقابة مع تعدد أدوار المستعملين و حقوق التحكم في النفاذ من أجل النفاذ الآمن و السري إلى البيانات في الحوسبة السحابية.Access control is very important in cloud data sharing. Especially in the domains like healthcare, it is essential to have access control mechanisms in place for confidentiality and secure data access. Attribute based encryption has been around for many years to secure data and provide controlled access. In this paper, we proposed a framework that supports circuit and attributes based encryption mechanism that involves multiple parties. They are data owner, data user, cloud server and attribute authority. An important feature of the proposed system is the verifiable delegation of the decryption process to cloud server. Data owner encrypts data and delegates decryption process to cloud. Cloud server performs partial decryption and then the final decrypted data are shared for users as per the privileges. Data owner  thus reduces computational complexity by delegating decryption process cloud server. We built a prototype application using the Microsoft.NET platform for proof of the concept. The empirical results revealed that there is controlled access with multiple user roles and access control rights for secure and confidential data access in cloud computing

A Survey: Attribute Based Encryption for Secure Cloud

Cloud computing is an enormous area which shares huge amount of data over cloud services and it has been increasing with its on-demand technology. Since, with these versatile cloud services, when the delicate data stored within the cloud storage servers, there are some difficulties which has to be managed like its Security Issues, Data Privacy, Data Confidentiality, Data Sharing and its integrity over the cloud servers dynamically. Also, the authenticity and data access control should be maintained in this wide environment. Thus, Attribute based Encryption (ABE) is a significant version of cryptographic technique in the cloud computing environment. Public Key Encryption acts as the basic technique for ABE where it provides one to many encryptions, here, the private key of users & the cipher-text both rely on attributes such that, when the set of the attributes of users key matches set of attributes of cipher-text with its corresponding access policy, only then decryption is possible. Thus, an opponent could grant access to the sensitive information that holds multiple keys, if it has at least one individual key for accession. The techniques based on ABE consist of two types: KP-ABE (Key- Policy ABE) where the user’s private key is linked to an access structure (or access policy) over attributes and cipher-text is connected to the set of attributes, and CP-ABE (cipher-text policy ABE) is vice versa. Hence, in this, Review we discuss about the various security techniques and relations based on Attributes Based Encryption, especially, the type KP-ABE over data attributes which explains secured methods & its schemes related to time specifications.&nbsp