Key Broadcast Research Articles

Two-party interactive secure deduplication with efficient data ownership management in cloud storage

Deduplication, which stores only one copy of duplicate data, is used extensively in cloud storage to reduce the overhead associated with storage. Unfortunately, client-side encryption prevents cloud storage from performing deduplication due to the randomness of traditional encryption. Some existing schemes can balance encryption and deduplication, but their interaction with third-party servers or online users adds additional overhead to the system. Also, the ownership of outsourced data will change frequently due to users’ requests to upload/delete/modify the data. But many existing schemes that can achieve dynamic ownership management have security flaws or require users to manage multiple keys. By focusing on these troubles, we have developed a secure deduplication scheme that does not rely on any third-party entities and supports data ownership management. More specifically, we take advantage of elliptic curve cryptography to design a key-sharing method so that different owners of the same data can share a random key only by interacting with the cloud service provider. And the broadcast encryption is used to manage the ownership of data, and this allows the cloud service provider to control users’ access to outsourced data by updating the broadcast key. In addition, the security analysis shows that the proposed scheme can meet the required security and that it outperforms other related schemes. The detailed simulation comparisons with other related schemes demonstrate that the proposed scheme has good performance.

BESTIE: Broadcast Encryption Scheme for Tiny IoT Equipment

In public key broadcast encryption, anyone can securely transmit a message to a group of receivers such that privileged users can decrypt it. The three important parameters of the broadcast encryption scheme are the length of the ciphertext, the size of private/public key, and the performance of encryption/decryption. It is suggested to decrease them as much as possible; however, it turns out that decreasing one increases the other in most schemes. This paper proposes a new broadcast encryption scheme for tiny Internet of Things (IoT) equipment (BESTIE), minimizing the private key size in each user. In the proposed scheme, the private key size is O(logn), the public key size is O(logn), the encryption time per subset is O(logn), the decryption time is O(logn), and the ciphertext text size is O(r), where n denotes the maximum number of users, and r indicates the number of revoked users. The proposed scheme is the first subset difference-based broadcast encryption scheme to reduce the private key size O(logn) without sacrificing the other parameters. We prove that our proposed scheme is secure under q-Simplified Multi-Exponent Bilinear Diffie-Hellman (q-SMEBDH) in the standard model.

Combinatorial Subset Difference-IoT-Friendly Subset Representation and Broadcast Encryption.

In the Internet of Things (IoT) systems, it is often required to deliver a secure message to a group of devices. The public key broadcast encryption is an efficient primitive to handle IoT broadcasts, by allowing a user (or a device) to broadcast encrypted messages to a group of legitimate devices. This paper proposes an IoT-friendly subset representation called Combinatorial Subset Difference (CSD), which generalizes the existing subset difference (SD) method by allowing wildcards (*) in any position of the bitstring. Based on the CSD representation, we first propose an algorithm to construct the CSD subset, and a CSD-based public key broadcast encryption scheme. By providing the most general subset representation, the proposed CSD-based construction achieves a minimal header size among the existing broadcast encryption. The experimental result shows that our CSD saves the header size by 17% on average and more than 1000 times when assuming a specific IoT example of IP address with 20 wildcards and total users, compared to the SD-based broadcast encryption. We prove the semantic security of CSD-based broadcast encryption under the standard l-BDHE assumption, and extend the construction to a chosen-ciphertext-attack (CCA)-secure version.

Adaptively secure certificate-based broadcast encryption and its application to cloud storage service

The existing public key broadcast encryption schemes are mainly constructed in identity-based cryptosystem, which bears the inherent problems of key escrow and key distribution. The certificate-based encryption mechanism can effectively address the problems in identity-based cryptosystem. Meanwhile, it simplifies the certificate revocation issue for traditional public key cryptosystem. Inspired by the idea of certificate-based encryption, we put forward the new primitive certificate-based broadcast encryption as well as its formal definition and security model. In virtue of prime order bilinear groups, we present an instantiation scheme of certificate-based broadcast encryption. To our best knowledge, the proposed scheme is the first adaptively secure scheme for certificate-based broadcast encryption in the standard model against chosen-ciphertext attack. Compared with the previous work, our scheme has advantages in the respects of computation cost as well as security properties. Furthermore, we present an application scenario of the proposed scheme for data access control in cloud storage service.

RETRACTED ARTICLE: Advanced resilient data consigning mechanism for mobile adhoc networks

Routing in network is a classic issue to be solved. To route the data among the nodes without any interruptions and without getting yield in any kind of malicious attack is a tedious task. Though there exist many routing techniques which were near success in the past some part of the problems are always left unsolved. Trust-based routing techniques and the bio-inspired path is connecting techniques area embedded together to solve this. The security of the proposed technique is given a big significance, which takes care of the rest of the key points. Initially, when a node tries to enter into the network which was already secured and confined by trustable nodes, we provide a two-way security check both from the new node and from the host node. This is made possible by applying digital signature algorithm, hash message authentication code, and message-digest algorithms for signature generations, hash value generation, and its corresponding encrypt and decrypt procedure. Elliptic curve Diffie–Hellman algorithm is used for certificate verification, after which the node is provided with the broadcast key. In the case of routing, ant colony optimization is applied to detect the best path for routing from root to destiny, and this path is again verified by trust frameworks and certain calculations. This highly secured verification and authentication process make the proposed advanced resilient data consigning mechanism (ARDC) stand out from the existing routing mechanisms. The proposed ARDC mechanism is analyzed against various network frameworks as throughput, packet loss, overhead, delivery ratio, delivery latency, and hop count and path reliability to prove its effectiveness. Further, the routing capability is also analyzed by comparing it against traditional DSR, destination-sequenced distance-vector and open shortest path first protocols.

Adaptively secure broadcast encryption with authenticated content distributors

In public key broadcast encryption systems, anyone could run the encryption algorithm to broadcast messages by using the public parameters. The unsupervised broadcast strategy allows malicious users (even though someone outside the system with the intentionally divulged public parameters) to distribute junk messages without responsibility. Consequently, content distributor authentication is essential for broadcast encryption systems to forbid spreading of junk information. In this work, we devise a solution for public key broadcast encryption system with adaptive security to resolve the aforementioned vicious broadcaster problem, which is neglected in the previous related works. In our scheme, any user could distribute an encryption of messages with both public parameters and his/her own secret keys, and each message is associated to its broadcaster. The construction is based on the composite order bilinear groups and its adaptive security depends on the hardness of the general subgroup decisional assumptions. Furthermore, this allows our scheme to be flexible in terms on the overhead of ciphertexts, which is constant sized. Compared with previous related broadcast encryption systems constructed in the composite order bilinear groups, our scheme inherits the superiority of adaptive security based non-interactive falsifiable assumption, and simultaneously achieves the optimal ciphertext overhead and the authentication of broadcasters.

Blockchain-Based Mutual-Healing Group Key Distribution Scheme in Unmanned Aerial Vehicles Ad-Hoc Network

A dynamic group key is required for secure communication in the Unmanned Aerial Vehicles Ad-Hoc Network (UAANET). However, due to the unreliable wireless channel and high-dynamic topology of UAANET, the situation that a node is missing certain group key broadcast messages occurs frequently. Existing group key distribution schemes cannot be directly applied to the UAANET, because of their poor security or real-time. Therefore, we present a mutual-healing group key distribution scheme based on the blockchain. Firstly, the Ground Control Station (GCS) builds a private blockchain where the group keys distributed by GCS are recorded. Meanwhile, through the blockchain, a dynamic list of UAANET membership certificates is also managed. According to different attack models, a basic mutual-healing protocol and an enhanced one are designed based on the Longest-Lost-Chain mechanism to recover the node's lost group keys with the aid of its neighbors. Security analysis and extensive experiments show that, compared with the existing mutual-healing schemes, our proposed solution can effectively resist various attacks with small overhead on time and storage.

Adaptively secure efficient broadcast encryption with constant-size secret key and ciphertext

In those broadcast application scenarios with a great quantity of receivers, e.g., the data access control system in cloud storage service, the single sender is apt to become the efficiency bottleneck of the system, because the computation and storage overhead of the sender will grow rapidly with the amount of qualified receivers. In order to overcome this problem, we first introduce the novel conception of complete binary identity tree which is adopted to manage the qualified receivers. Then we design the prune-merge algorithm to further optimize the structure of the tree and cut down the amount of receivers. The algorithm effectively reduces the computation and storage cost of the trusted authority in the system. Subsequently, in virtue of composite-order bilinear groups, we bring forward an efficient public key broadcast encryption scheme combined its application to the system of data access control in cloud storage service. Compared with the existing schemes, the lengths of system public parameters, secret key and ciphertext in our scheme are all constant. In addition, the number of secret keys in our scheme increases logarithmically with the maximum amount of receivers, while the numbers of secret keys in the existing schemes increase linearly with the maximum amount of receivers. Furthermore, the proposed scheme is proved to guarantee adaptive security under general subgroup decision assumption in the standard model. The performance analysis manifests that our scheme is feasible for those broadcast applications with fixed senders.

Authenticated public key broadcast encryption with short ciphertexts

Broadcast encryption allows a broadcaster, who wants to distribute messages to a chosen subset of receivers, to produce an encrypted content and transmit it via a broadcast channel. Normally we think that it is preferable if the broadcast encryption system is a public-key cryptosystem, which permits anybody could encrypt and distribute messages with public parameters. Nevertheless, such a broadcast strategy brings along a slew of diffusions of the spam that are uncontrollable. Authenticated public key broadcast encryption ensures that no such strategy can succeed - the encryption algorithm creates ciphertext with public key and the broadcaster’s secret key. It means that each broadcasted message is associated to the content distributor in order to ensure accountability. Technically, it embeds a signature in the ciphertext and each authorized users could verify it during decrypting. In this paper, we construct a solution for authenticated public key broadcast encryption using bilinear maps where the ciphertext is of O(1) (only constant number of group elements). The public key size and user private key are of size O(N) (N is the total number of users). The simulation experiment results indicated that the size of public key (private key) is about 4MB where we arbitrarily set N = 100000. Finally, we define the security for authenticated public key broadcast encryption and show that our construction captures static security in the standard model.

Layered quantum key distribution

We introduce a family of QKD protocols for distributing shared random keys within a network of $n$ users. The advantage of these protocols is that any possible key structure needed within the network, including broadcast keys shared among subsets of users, can be implemented by using a particular multi-partite high-dimensional quantum state. This approach is more efficient in the number of quantum channel uses than conventional quantum key distribution using bipartite links. Additionally, multi-partite high-dimensional quantum states are becoming readily available in quantum photonic labs, making the proposed protocols implementable using current technology.

KDSR

This article deals with a key distribution protocol to secure routing in large-scale Wireless Sensor Networks (WSNs) and proposes a new protocol called KDSR. The authors' protocol has two originalities: to provide a secure network structure for large-scale WSNs, and to use lightweight local process to share efficiently the Local Broadcast Keys, the Pairwise Keys and the Global Broadcast Key. These keys are useful to secure several communication patterns in WSNs: one-to-many, one-to-one and one-to-all. Security analyses show that KDSR can withstand several attacks against WSNs. Through fast node revocation process, KDSR offers a good resilience against node capture. Immunity against MiM and replay attacks are well checked with the AVISPA tools. The experimentations are done on real TelosB motes and through the TOSSIM simulator. Simulation results confirm that KDSR is scalable, provides a good key connectivity and a good resilience. Comparison to earlier work shows that KDSR causes less computation complexity, less communication overhead and much less storage space even for large-scale WSNs.

Mutual healing enabled group-key distribution protocol in Wireless Sensor Networks

The unreliable wireless medium for communication within a Wireless Sensor Network (WSN) necessitates equipping the sensor nodes with shared secrets to protect the communication en-route. In order to establish a dynamic session secret amongst a group of sensor nodes in a WSN, group-key broadcast is found to be a workable solution. However, when a node misses one or more group-key broadcast messages, rebroadcasting results in additional energy consumption at node end and increased network traffic as well. Self-healing mechanism is, therefore, used to recover the lost broadcasts using a future session broadcast. A node, that has missed multiple consecutive broadcasts and does not want to wait for a future broadcast, can obtain the session key through mutual-healing with the help of a neighbor node. In this paper, we present a secure and efficient mutual-healing protocol that uses Chinese remainder theorem(CRT) based secret sharing for group key broadcast. During mutual-healing, mutual authentication and key confirmation are provided. The probability of an unauthorized member retrieving a past session key through self-healing or responding to a mutual-healing request as a neighbor node is shown negligible. The experimental results show that the proposed protocol provides significant performance improvement in terms of computation, communication and storage overhead as compared to existing mutual-healing protocols.

Adaptively Secure Broadcast Encryption With Constant Ciphertexts

In this paper, we present a new public key broadcast encryption (BE) for achieving adaptive security against arbitrary number of colluders. Specifically, our scheme is built from composite order multilinear maps and enjoys ciphertext overhead of a constant number of group elements which are ${O}$ (1) bits. Furthermore, the private key size and public key size are all poly-logarithmic in the total number of users. Herein, we generalize the methodology of Lewko and Waters for realizing dual system encryption to the composite order multilinear groups, and then prove the adaptive security of our scheme under static assumptions in the standard model. Compared with the state-of-the-art, our scheme achieves the adaptive security in simple and non-interactive falsifiable assumptions with the optimized parameter size for BE.

An Efficient and Provably-Secure Broadcast Authentication Scheme in Wireless Sensor Networks

Broadcast authentication is a security mechanism in Wireless Sensor Networks (WSNs), which enables a lot of entities to join in and disseminate the messages into the networks in an authenticated way. Hitherto, some symmetric key based broadcast authentication schemes such as μTESLA and its variants have been proposed to provide such services for wireless sensor networks. Unfortunately, these schemes suffer from serious Denial of Service (DoS) attack due to the time delay in message authentication. In this paper, we propose a certificateless signature based broadcast authentication scheme without bilinear pairing in wireless sensor networks. Our proposal is proved to be secure in the random oracle model under the hardness assumption of discrete logarithm problem. Compared with the previous protocols, the perform evaluations show that this scheme is efficient and appropriate to be applied in wireless sensor networks.

Tree based symmetric key broadcast encryption

The most influential broadcast encryption (BE) scheme till date was introduced in 2001 by Naor, Naor and Lotspiech (NNL) and is based on binary trees. This paper generalizes the ideas of NNL to obtain BE schemes based on k-ary trees for any k≥2. The treatment is uniform across all k and essentially provides a single scheme which is parameterized by the arity of the underlying tree. We perform an extensive analysis of the header length and user storage of the scheme. It is shown that for a k-ary tree with n users out of which r are revoked, the maximum header length is min⁡(2r−1,n−r,⌈n/k⌉). An expression for the expected header length is obtained and it is shown that the expression can be evaluated in O(rlog⁡n) time. Experimental results indicate that for values of r one would expect in applications such as pay TV systems, the average header length decreases as k increases. The number of keys to be stored by any user is shown to be at most (χk−2)ℓ0(ℓ0+1)/2, where ℓ0=⌈logk⁡n⌉ and χk is the number of cyclotomic cosets modulo 2k−1. In particular, when the number of users is more than 1024, we prove that the user storage required for k=3 is less than that of k=2. For higher values of k, the user storage is greater than that for binary trees. The option of choosing the value of k provides a designer of a BE system with a wider range of trade-offs between average header length and user storage. The effect of layering on the k-ary tree SD scheme is also explored.

Adaptively Anonymous Public-Key Broadcast Encryption Scheme without Random Oracle

Anonymous is one of the most important security properties for kinds of Internet applications. In this paper, we consider the privacy-preserving problem in the context of public key broadcast encryption. We provide a new security definition for anonymous public key broadcast encryption, and construct a new scheme. To achieve anonymous, we blind the ciphertexts using the random factors. Moreover, we use a pair of orthogonal bases to construct secret key and ciphertexts for proper decryption. Our anonymous publickey broadcast encryption scheme can be proven in the adaptive model without random oracle. The key technique used to obtain our result is an elaborate combination of the dual system encryption proposed by Waters and a new approach on bilinear pairings using the notion of dual pairing vector spaces (DPVS) proposed by Okamoto and Takasima.

Key continual-leakage resilient broadcast cryptosystem from dual system in broadcast networks

In order to tolerate possible leakage of secret keys, leakage-resilient cryptosystem models a class of attractive leakage output by allowing an adversary to provide any computable leakage function and learning the partial keys or other possible internal states from the output of function. In this work, we present an adaptively secure broadcast encryption resilient to key continual leakage in the standard model. Our scheme provides the tolerance of continual leakage, in which any user can generate multiple private keys per user by periodically updating the key. We use the dual system encryption mechanism to implement the leakage resilience and adaptive security, and intrinsically set an algorithm to refresh a key and produce a same distributed new key. We also give the evaluation of the leakage bound and leakage fraction, and the simulations show that our scheme can tolerate about 71% leakage fraction with 3.34 × 10−52 failure probability in standard 80-bit security level when we adjust the leakage factor to allow the private key to be 100 Kb.

복호화 위임을 제공하는 효율적인 브로드캐스트 암호시스템

브로드캐스트 암호시스템은 송신자가 수신자 집합을 지정하여 생성한 암호문을 공개된 채널을 통해 전송하면, 수신자 집합에 속하는 정당한 사용자만이 메시지를 복호화 할 수 있는 암호 기법이다. 2005년도에는 공모공격에 안전하며 상수크기의 암호문과 비밀키를 가지는 페어링 기반의 기법이 Boneh 등에 의해 제안되었다. 일반적으로 페어링 기반의 기법은 사용자로부터 많은 연산량을 요구하기 때문에 리소스에 제한이 있는 기기에 적용하기에는 어려움이 있었다. 본 논문에서는 Boneh 등의 기법을 기반으로 브로드캐스트 암호시스템에서 암호문을 효율적으로 복호화 하는 기법(BEWD)을 제안한다. 제안하는 기법에서는 복호화 시에 요구되는 페어링연산과 다른 사용자들의 공개키가 쓰이는 연산을 제 3자인 프록시 서버에 위임함으로써 사용자에게 요구되는 연산량을 줄인다. 또한 사용자는 서버의 올바른 계산을 확인을 할 수 있다. 제안하는 기법은 n-BDHE가정 하에 선택적인 IND-RCCA에 안전한 기법이다. In a Broadcast Encryption System, a sender sends an encrypted message to a large set of receivers at once over an insecure channel and it enables only users in a target set to decrypt the message with their private keys. In 2005, Boneh et al. proposed a fully collusion-resistant public key broadcast encryption in which the ciphertext and the privatekey sizes are constant. In general, pairing-based broadcast encryption system is efficient in bandwidth and storing aspects than non-pairing based broadcast encryption system, however, it requires many computational costs that resource-constrained devices is not suit to be applied. In this paper, we propose a Broadcast Encryption scheme(called BEWD) that user can decrypt a ciphertext more efficiently. The scheme is based on Boneh et al.scheme. More precisely, it reduces receiver's computational costs by delegating pairing computation to a proxy server which computation is required to receiver in Boneh et al.scheme. Furthermore, the scheme enables a user to check if the proxy server compute correctly. We show that our scheme is secure against selective IND-RCCA adversaries under l-BDHE assumption.

Transmission-Efficient Broadcast Encryption Scheme with Personalized Messages

Broadcast encryption scheme with personalized messages (BEPM) is a new primitive that allows a broadcaster to encrypt both a common message and individual messages. BEPM is necessary in applications where individual messages include information related to user's privacy. Recently, Fujii et al. suggested a BEPM that is extended from a public key broadcast encryption (PKBE) scheme by Boneh, Gentry, and Waters. In this paper, we point out that 1) Conditional Access System using Fujii et al.'s BEPM should be revised in a way that decryption algorithm takes as input public key as well, and 2) performance analysis of Fujii et al.'s BEPM should be done depending on whether the public key is transmitted along with ciphertext or stored into user's device. Finally, we propose a new BEPM that is transmission-efficient, while preserving O(1) user storage cost. Our construction is based on a PKBE scheme suggested by Park, Kim, Sung, and Lee, which is also considered as being one of the best PKBE schemes.

Design and Implementation of a Novel Intelligent Curtain Module System

Intelligent curtain system can be time switch and achieve more advanced control functions as scene control. The paper introduced curtain applications, electric curtain classification as well as intelligent curtain with new functions. Based on requirements analysis on intelligent curtain of hotel room, functional division of intelligent curtain module was determined. MCU control circuit, data storage circuit and motor drive circuit were designed. The I/O interface of AT89C4051 was used to implement functions of key signal input, voice broadcast or timekeeping. CAN bus was used for communication to complete required curtain linkage function when guest plug card.