We present TendrilStaller, an eclipse attack targeting at Bitcoin's peer-to-peer network. TendrilStaller enables an adversary to delay block propagation to a victim for 10 minutes. The adversary thus impedes the victim from getting the latest blockchain state. It only takes as few as one Bitcoin full node and two light weight nodes to perform the attack. The light weight nodes perform a subset of the functions of a full Bitcoin node. The attack exploits a recent block propagation protocol introduced in April 2016. The protocol prescribes a Bitcoin node to select 3 neighbors that can send new blocks unsolicited. These neighbors are selected based on their recent performance in providing blocks quickly. The adversary induces the victim to select 3 attack nodes by having attack nodes send valid blocks to the victim more quickly than other neighbors. For this purpose, the adversary deploys a handful of light weight nodes so that the adversary itself receives new blocks faster. The adversary then performs the attack to delay blocks propagated to the victim. We implement the attack on top of current default Bitcoin protocol We deploy the attack nodes in multiple locations around the globe and randomly select victim nodes. Depending on the round-trip time between the adversary and the victim, 50%-85% of the blocks could be delayed to the victim. We further show that the adoption of light weight nodes greatly increases the attack probability by 15% in average. Finally, we propose several countermeasures to mitigate this eclipse attack.
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Deception of Certificates is the major issue that is faced by the educational sector. In order to prevent forgery of certificates and to provide a secure certificate verification environment an authenticated system application is developed using blockchain with smart contracts. The immutability property of blockchain prevents the data stored from being manipulated and helps in implementing a verification system. The system generates a new block for every user in the blockchain. These blockchain are replicated across all the nodes involved in a Peer-to-Peer network and thus it improves the reliability of the system. Whenever a user is validated, their certificates are digitally provided by the system to the user along with a Quick Response code. This helps in sharing of certificates between the employers. The authenticity of certificates is improved by embedding the certificates with imperceptible watermark using the alpha blending process. This helps to avoid various attacks at different phases of certificate distribution.
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
The pioneer blockchain platform Bitcoin has drawn massive attention from various sectors in society, with its promising decentralized, irreversible, and trust-free natures. Increasing volume of Bitcoin transactions makes it impractical for each user to store a full copy of whole ledger, especially for a normal user who makes few transactions and owns constrained storage space. There are already some works conducted to reduce the storage overhead by redesigning the system protocol, based on different trust assumptions. An example is running light nodes, which trust the full nodes to store its relevant data and reply to its data request timely. However, it introduces the risks of permanent data loss, as the data relevant to a light node may be tailored by all the full nodes later. Another attempt is conducted by organizing the nodes into several cooperative units based on a trust assumption, which is hard to satisfy in practice. In this paper, we propose a novel Jigsaw-like Data Reduction (Jidar) approach. Each node in Jidar only stores transactions of interest and relevant Merkle branches from the complete blocks, just like selecting several pieces from the jigsaw puzzles. A node can maintain and verify all its relevant data locally and safely without any trust assumptions. To verify the validity of a newly proposed transaction, Merkle branches relevant to the inputs are provided along with the transaction by the proposer. In view of the requirement that a user wants to cohere all the fragments stored in different nodes into a complete block, just like stitching all the pieces into a complete jigsaw-puzzle picture, a mechanism to query full data is added to Jidar. Experimental results demonstrate that Jidar can reduce a normal node's storage cost to about 1.03% of the original Bitcoin system at a low communication cost
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
With the prevalence of blockchain, more and more Decentralized Applications (DApps) are deployed on Ethereum to achieve the goal of communicating without supervision. Users habits may be leaked while these applications adopt SSL/TLS to encrypt their transmission data. Encrypted protocol and the same blockchain platform bring challenges to the traffic classification of DApps. Existing encrypted traffic classification methods suffer from low accuracy in the situation of DApps.
2 source records
Internet Traffic Analysis and Secure E-voting
Advanced Steganography and Watermarking Techniques
Daehwa Rayer Lee, Yunhee Jang, Hanbin Jang, Hyoungshick Kim
Recently, Samsung released Galaxy S10 supporting the cryptowallet feature [5]. However, it is still questionable whether cryptocurrency can be popularly used for mobile payments because processing transactions in existing blockchain systems are too slow. For example, public blockchain systems such as Bitcoin [6] (7 transactions per second (TPS)) and Ethereum (15 TPS) are significantly slower than mainstream payment systems such as Visa (2,000 TPS) using a centralized database.
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Advanced Steganography and Watermarking Techniques
A permissioned blockchain platform comes with numerous assurances such as transaction confidentiality and system scalability to several organizations. Most permissioned blockchains rely on a Public-Key Infrastructure (PKI)as cryptographic tools to provide security services such as identity authentication and data confidentiality. Using PKI to validate transactions includes validating digital certificates of endorsement peers which creates an overhead in the system. Because public-key operations are computationally intensive, they limit the scalability of blockchain applications. Due to a large modulus size and expensive modular exponentiation operations, public-key operations such as RSA become slower than polynomial-based schemes, which involve a smaller modulus size and a less smaller number of modular multiplications. For instance, the 2048-bit RSA is approximately 15,728 times slower than a polynomial with a degree of 50 and 128-bit modulus size. In this paper, we propose a lightweight polynomial-based key management scheme in the context of a permissioned blockchain. Our scheme involves computationally less intensive polynomial evaluation operations such as additions and multiplications that result in a faster processing compared with public-key schemes. In addition, our proposed solution reduces the overhead of processing transactions and improves the system scalability. Security and performance analysis are provided in the paper.
Blockchain Technology Applications and Security
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
In the paper a new approach for protecting video files from unauthorized changes using the Blockchain technology and cloud services is proposed. The essence of our approach consists in hash function calculating for each frame and forming the blocks sequence of calculated hash functions for all frames of video file. The hash function blocks are sent to the Blockchain cloud storage, which is trusted by all interested parties.
Information Systems and Technology Applications
Advanced Steganography and Watermarking Techniques
Let’s put aside the question whether Blockchain is a real technology or a passing fad – a hype. The ups and downs of your fortunes in Bitcoin and similar cryptocurrencies in the last couple of years may have clouded your views. Short-term or long-term success, or failure, of cryptocurrencies may depend on the success, or failure, of Blockchain, but it is important to recognize that Blockchain and the Distributed Ledger Technology (DLT) have far greater uses in wide-ranging applications. One such use of Blockchain is as a key enabling technology of 5G applications. Prof. Chaudhry and Dr. Asad present their research to propose a Blockchain-based Network Slice and Resource Brokerage system to build an open, transparent, and fair 5G ecosystem. They explain the challenges of addressing the massive cooperation required among 5G devices and potential solutions using Blockchain.
Open access
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Advanced Steganography and Watermarking Techniques
Blockchains are emerging technologies that propose new business models and value propositions. Besides their application for cryptocurrency purposes, as distributed ledgers of transactions, they enable new ways to provision trusted information in a distributed fashion. In this paper, we present our product tagging solution designed to help Small & Medium Enterprises (SMEs) protect their brands against counterfeit products and parallel markets, as well as to enhance UX (User Experience) and promote the brand and product.Our solution combines the use of DLT to assure, in a verifiable and permanent way, the trustworthiness and confidentiality of the information associated to the goods and the innovative CP-ABE encryption technique to differentiate accessibility to the product's information.
Blockchain Technology Applications and Security
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
Stored-value cards are used more and more widely. But there are some problems in the present stored-value card platform: 1. The service agreement of stored-value card is not clear enough; 2. The refund process of users is inconvenient; 3. The transfer of stored-value can not be realized among users; 4. The security of accounts is not guaranteed. Smart contracts are computer contracts written in code, which are enforced directly by computers. This paper proposes a stored-value card platform in which the service contracts are expressed with smart contracts. The smart contract is executed on the blockchain. Blockchain technology, in which accounts are decentralized and data is resistant to modification, is applied to improving reliability in the consumption process. The platform is built on the private blockchains of Ethereum, which is designed for small merchants. ECDSA (Elliptic Curve Digital Signature Algorithms) is used to asymmetrically encrypt accounts. Some functions, such as stored-value issuance, stored-value consumption, commodity purchase, are designed in this system.
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Sebastian Henningsen, Daniel Teunis, Martin Florian, Björn Scheuermann
Ethereum is a decentralized Blockchain system that supports the execution of Turing-complete smart contracts. Although the security of the Ethereum ecosystem has been studied in the past, the network layer has been mostly neglected. We show that Go Ethereum (Geth), the most widely used Ethereum implementation, is vulnerable to eclipse attacks, effectively circumventing recently introduced (Geth v1.8.0) security enhancements. We responsibly disclosed the vulnerability to core Ethereum developers; the corresponding countermeasures to our attack where incorporated into the v1.9.0 release of Geth. Our false friends attack exploits the Kademlia-inspired peer discovery logic used by Geth and enables a low-resource eclipsing of long-running, remote victim nodes. An adversary only needs two hosts in distinct /24 subnets to launch the eclipse, which can then be leveraged to filter the victim's view of the Blockchain. We discuss fundamental properties of Geth's node discovery logic that enable the false friends attack, as well as proposed and implemented countermeasures.
Open access
3 source records
Peer-to-Peer Network Technologies
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Electronic voting (e-voting) is an electronic means for casting and counting votes. It is an efficient and cost-effective way for conducting a voting procedure, which has characteristic of being magnanimous data and real time and requesting high safety. However, concerns on security of networking and privacy of communication for e-voting have been grown. Securing e-voting is very urgent and has becoming a popular topic in the area of communications and networking. We present techniques to exploit blockchain in P2P network to improve the security of e-voting. First, we design a synchronized model of voting records based on distributed ledger technology (DLT) to avoid forgery of votes. Second, we design a user credential model based on elliptic curve cryptography (ECC) to provide authentication and non-repudiation. Third, we design a withdrawal model that allows voters to change their vote before a preset deadline. By integrating the above designs, a blockchain-based e-voting scheme in P2P network is proposed for essential requirements of e-voting process. To prove and verify the scheme, a blockchain-based e-voting system for multiple candidates has been designed on Linux platforms in P2P network. The system involves electronic voting theory, cryptography, and software engineering theory. The implementation result shows that it is a practical and secure e-voting system, which solves the problem on forgery of votes during e-voting. The blockchain-based e-voting system can be applied to a variety of networking applications directly.
Open access
Internet Traffic Analysis and Secure E-voting
Advanced Steganography and Watermarking Techniques
Decentralization for data storage is a challenging problem for blockchain-based solutions as the blocksize plays the key role for scalability. In addition, specific requirements of multimedia data calls for various changes in the blockchain technology internals. Considering one of the most popular applications of secure multimedia streaming, i.e., video surveillance, it is not clear how to judiciously encode incentivization, immutability and compression into a viable ecosystem. In this study, we provide a genuine scheme that achieves this encoding for a video surveillance application. The proposed scheme provides a novel integration of data compression, immutable off-chain data storage using a new consensus protocol namely, Proof-of-WorkStore (PoWS) in order to enable fully useful work to be performed by the miner nodes of the network. The proposed idea is the first step towards achieving greener application of blockchain-based environment to the video storage business that utilizes system resources efficiently.
Open access
2 source records
cs.DC
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Jia Fan, Zhen Wang, Yili Luo, Jian Bai · 6 authors
Stealth address has been an effective way to protect privacy of users in blockchain. However, most of the existing schemes either require their users to bear extra storage costs to manage keys, or need one more private communication before each transaction. To overcome these drawbacks, we proposed a new kind of stealth addresses scheme in which a user only needs to keep a single key pair for initial certificate, the user only stores his or her initial key pair for all transactions. In our scheme, when a sender initiates a transaction, he or she creates a one-time transaction address, then the sender attaches it to the transaction. The receiver uses his or her private key to check the transaction from the blockchain, no private channel is needed for each transaction. Considering regulatory issues, transactions can be wholly or partially regulated, depending on security requirements. Finally, we provide provable security analysis to ensure the security of our scheme, and our simulation results show that our scheme is also efficient and practical in computation.
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Motivated by analyzing anonymity properties of Bitcoin network and identification of the origin of illegal transactions, we study the problem of detecting the source node of a transaction message in the Bitcoin network, based on the present spreading model-diffusion. We start by adopting a listening model to get the information of which part of nodes have received the message, say an observation, which is an important premise of solving source detection problem. We propose an estimator for regular trees based on independent multi-reporting observations, and theoretically give a lower bound of the correct detection probability when the observation moment tends to infinity. We show that the more independent reporting observations we have, the higher the probability of detection is, and it further approaches one. The effectiveness of our source estimator is also established in several simulations.
Advanced Steganography and Watermarking Techniques
Bitcoin is a Cryptocurrency which is evolving in digital world and gaining a larger market related to digital currency and stands on all the user expectation of decentralize mechanism of system by providing proof of work in peer-to-peer network with the help of Blockchain. In this paper I have done a literature review on Blockchain technology and its application in Bitcoin.
Open access
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Ethereum is an open-source, public, blockchain-based distributed computing platform and operating system featuring smart contract functionality. In this paper, we proposed an Ethereum based eletronic voting (e-voting) protocol, Ques-Chain, which can ensure the authentication can be done without hurting confidentiality and the anonymity can be protected without problems of scams at the same time. Furthermore, the authors considered the wider usages Ques-Chain can be applied on, pointing out that it is able to process all kinds of messages and can be used in all fields with similar needs.
Xingjie Yu, Michael Shiwen Thang, Yingjiu Li, Robert H. Deng
In Bitcoin network, the distributed storage of multiple copies of the block chain opens up possibilities for double-spending, i.e., a payer issues two separate transactions to two different payees transferring the same coins. While Bitcoin has inherent security mechanism to prevent double-spending attacks, it requires a certain amount of time to detect the double-spending attacks after the transaction has been initiated. Therefore, it is impractical to protect the payees from suffering in double-spending attacks in fast payment scenarios where the time between the exchange of currency and goods or services is shorten to few seconds. Although we cannot prevent double-spending attacks immediately for fast payments, decentralized non-equivocation contracts have been proposed to penalize the malicious payer after the attacks have been detected. The basic idea of these contracts is that the payer locks some coins in a deposit when he initiates a transaction with the payee. If the payer double-spends, a cryptographic primitive called accountable assertions can be used to reveal his Bitcoin credentials for the deposit. Thus, the malicious payer could be penalized by the loss of deposit coins. However, such decentralized non-equivocation contracts are subjected to collusion attacks where the payer colludes with the beneficiary of the depoist and transfers the Bitcoin deposit back to himself when he double-spends, resulting in no penalties. On the other hand, even if the beneficiary behaves honestly, the victim payee cannot get any compensation directly from the deposit in the original design. To prevent such collusion attacks, we design fair time-locked deposits for Bitcoin transactions to defend against double-spending. The fair deposits ensure that the payer will be penalized by the loss of his deposit coins if he double-spends and the victim payee’s loss will be compensated within a locked time period. We start with the protocols of making a deposit for one transaction. In particular, for the transaction with single input and output and the transaction with multiple inputs and outputs, we provide different designs of the deposits. We analyze the performance of deposits made for one transaction and show how the fair deposits work efficiently in Bitcoin. We also provide protocols of making a deposit for multiple transactions, which can reduce the burdens of a honest payer. In the end, we extend the fair deposits to non-equivocation contracts for other distributed systems.
Blockchain Technology Applications and Security
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
Reza M. Parizi, Sajad Homayoun, Abbas Yazdinejad, Ali Dehghantanha · 5 authors
Blockchains are turning into decentralized computing platforms and are getting worldwide recognition for their unique advantages. There is an emerging trend beyond payments that blockchains could enable a new breed of decentralized applications, and serve as the foundation for Internet's security infrastructure. The immutable nature of the blockchain makes it a winner on security and transparency; it is nearly inconceivable for ledgers to be altered in a way not instantly clear to every single user involved. However, most blockchains fall short in privacy aspects, particularly in data protection. Garlic Routing and Onion Routing are two of major Privacy Enhancing Techniques (PETs) which are popular for anonymization and security. Garlic Routing is a methodology using by I2P Anonymous Network to hide the identity of sender and receiver of data packets by bundling multiple messages into a layered encryption structure. The Onion Routing attempts to provide low-latency Internet-based connections that resist traffic analysis, deanonymization attack, eavesdropping, and other attacks both by outsiders (e.g. Internet routers) and insiders (Onion Routing servers themselves). As there are a few controversies over the rate of resistance of these two techniques to privacy attacks, we propose a PET-Enabled Sidechain (PETES) as a new privacy enhancing technique by integrating Garlic Routing and Onion Routing into a Garlic Onion Routing (GOR) framework suitable to the structure of blockchains. The preliminary proposed GOR aims to improve the privacy of transactions in blockchains via PETES structure.
The Internet of Things (IoT) visualizes a massive network with billions of interaction among smart things which are capable of contributing all sorts of services. Self-configuring things (nodes) are connected dynamically with a global network in IoT scenario. The small things are widely spread in a real world paradigm with minimal processing capacity and limited storage. The recent IoT technologies have more concerns about the security, privacy and reliability. Sharing personal data over the centralized system still remains as a challenging task. If the infrastructure is able to provide the assurance for transferring the data but for now it requires special attention on security and data consistency. Because, centralized system and infrastructure is viewed as a more attractive point for hacker or cyber-attacker. To solve this we present a secured smart contract based on Blockchain to develop a secured communicative network. A Hash based secret key is used for encryption and decryption purposes. A demo attack is done for developing a better understanding on blockchain technology in terms of their comparison and calculation.
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Multimedia data, especially images are increasing dramatically. Images published on the Web are more often facing the risk of being tampered or manipulated since their content is easily mutable. Using blockchain technology provides advantages and, at the same time, challenges when dealing with this issue due to the following reasons: (a) data in a blockchain are well saved and immutable and (b) adding the data directly to a blockchain may consume much time which makes it computationally and economically expensive. Thus, we propose a blockchain-based solution which considers two key aspects: First, using a blockchain to register information about ownership and copyrights for authors, as well as descriptive information of an image, used to detect copyright violations. Second, avoiding insertion of raw image data into the blockchain, but storing only unique descriptive metadata about the images, allowing for a more efficient implementation of the system. This work considers different well-known image matching approaches to validate the power of the proposed approach, which allows for an efficient checking of violations of copyrights for a given image.
Advanced Image and Video Retrieval Techniques
Advanced Steganography and Watermarking Techniques