Simulation of the Internet Computer Protocol: the Next Generation Multi-Blockchain Architecture

The Internet Computer Protocol is a new generation blockchain that aims to provide better security and scalability than the traditional blockchain solutions. In this paper, this innovative distributed computing architecture is introduced, modeled and then simulated by means of an agent-based simulation. The result is a digital twin of the current Internet Computer, to be exploited to drive future design and development optimizations, investigate its performance, and evaluate the resilience of this distributed system to some security attacks. Preliminary performance measurements on the digital twin and simulation scalability results are collected and discussed. The study also confirms that agent-based simulation is a prominent simulation strategy to develop digital twins of complex distributed systems

Modelling of the Internet Computer Protocol Architecture: the Next Generation Blockchain

The Internet Computer Protocol is described as a third-generation blockchain system that aims to provide secure and scalable distributed systems through blockchains and smart contracts. In this position paper, this innovative architecture is introduced and then discussed in view of its modeling and simulation aspects. In fact, a properly defined digital twin of the Internet Computer Protocol could help its design, development, and evaluation in terms of performance and resilience to specific security attacks. To this extent, we propose a multi-level simulation model that follows an agent-based paradigm. The main issues of the modeling and simulation, and the main expected outcomes, are described and discussed

An Auditable Confidentiality Protocol for Blockchain Transactions

Blockchain exposes all users’ transaction data to the public, including account balances, asset holdings, trading history, etc. Such data exposure leads to potential security and personal privacy risks that restrict blockchain from broader adoption. Although some existing projects focus on single-chain confidential payment, no existing cross-chain system supports private transactions yet, which is incompatible with privacy regulations such as GDPR. Also, current confidential payment systems require users to pay high extra fees. However, a private and anonymous protocol encrypting all transaction data raises concerns about malicious and illegal activities since the protocol is difficult to audit. We need to balance privacy and auditability in blockchain. We propose an auditable and affordable protocol for cross-chain and single-chain transactions. This protocol leverages zero-knowledge proofs to encrypt transactions and perform validation without disclosing sensitive users\u27 data. To meet regulations, each auditor from an auditing committee will have an encrypted secret share of the transaction data. Auditors may view the private transaction data only if a majority of the committee agrees to decrypt the data. We employ a ZK-rollup scheme by processing multiple transactions in batches, which reduces private transaction costs to 90\% lower compared with solutions without ZK-rollup. We implemented the proposed scheme using Zokrates and Solidity and evaluated the protocol on the Ethereum test network, and the total one-to-one private transactions cost only 5 seconds. We also proved the security of the protocol utilizing the standard real/ideal world paradigm

On Explicit Depth Robust Graphs

We study the problem defined by Erd˝os and Szemer�edi in 1975 of constructing sparse depthrobust graphs. Recall that a directed acyclic graph G is (e, d)-depth-robust if it is guaranteed to contain a path of length d even after the deletion of any e nodes and all of their incident edges. The original construction (of nearly optimal depth-robust graphs) of Erd˝os and Szemer�edi required logarithmic in-degree and subsequent work by Mahmoody, Moran, and Vadhan made that construction explicit. One of the major open questions left since that 1975 seminal work was to construct depth-robust graphs of constant degree. Our contribution is the first explicit construction of constant-degree depth-robust graphs. Our construction too enjoys nearly optimal depth-robustness. We accomplish this via a novel expanding graph product operator X that takes three input graphs (G, H, X) with special properties and outputs a new graph. Informally, we show that our operator provides the following guarantee: if G and H are depth-robust graphs and H is a constant-degree expanding graph [RVW00], then G ∗ = X(G, H, X) is a depth-robust graph of size |G| � |H| whose degree depends only additively on degrees of H and X. We then show that the recursive application of the expanding graph product operator yields a simple and explicit iterative construction for constant-degree depth-robust graphs of arbitrary size. In particular, we show that a graph of size n will enjoy (Ω(n ^(1−epsilon) ), Ω(n ^(1−epsilon) ))-depth-robustness for any epsilon > 0 and give an algorithm for computing labels of all nodes that have a direct edge to/from a given node labeled i in time poly(log i). Ours is the first explicitly constructed constant-degree depth robust graph with guaranteed lower bounds on its depth-robustness (in contrast to only probabilistic ii guarantees). Previous explicit constructions were of logarithmic degree or worked only with probability < 1. Beyond theoretical relevance, our construction has practical implications including a new data-independent memory-hard function (iMHF), a desirable cryptographic primitive for crypto-currencies, with guaranteed lower bounds on its memory complexity

A matching model for Construction subcontractor selection in Engineering bid decisions using Ordinal priority approach

In recent years, the two-sided matching theory has been applied in various fields. Its influence in the engineering field is becoming more and more significant. In the construction engineering context, from the contractor’s perspective as the decision-maker, the mutual matching between project bidding and subcontractors is a complex and uncertain process. A suitable matching method needs to be selected according to the particular situation. Since this study requires considering both the highest satisfaction of parties and the weight of individual fulfillment, we use the two-sided matching theory to address the mutual matching between the engineering project bidding and subcontractor. At the same time, the Ordinal Priority Approach (OPA) is employed to determine the weights and evaluate the indicators of both parties and then determine the preference between the two parties, effectively avoiding the deviation caused by subjective influence in the process. As a result, a bilateral matching model is proposed with the highest satisfaction and considering individual satisfaction. Finally, an example is presented to verify the feasibility and effectiveness of the proposed model

Linguistic Repertoires Embodied and Digitalized: A Computer-Vision-Aided Analysis of the Language Portraits by Multilingual Youth

The present study sets out to investigate how multilingual youth perceive and represent their linguistic repertoires. To achieve this goal, we introduced a computer-vision-aided analytical method to deal with the obtained visual data, which comprised digital images of language portraits created by a group of young multilingual speakers. An OpenCV module is used to build and complete the graphic data processing, enabling quantitative evaluations of participants’ colored clusters and linguistic codes that express their language repertoires. In combination with oral narratives provided in their language portraits, the findings demonstrate that Macanese heritage speakers show a higher degree of “scope” than the Chinese mainland sojourners in Macao but a lower degree of “access”. Follow-up interviews further corroborated the self-perceptions of their linguistic resources across different registers. Overall, the computer-vision-aided analysis of language portraits enhances the current understanding of the “scope” and “access” of multilingual repertoires in lived experience

Simulation of the Internet Computer Protocol: the Next Generation Multi-Blockchain Architecture

The Internet Computer Protocol is a new generation blockchain that aims to provide better security and scalability than the traditional blockchain solutions. In this paper, this innovative distributed computing architecture is introduced, modeled and then simulated by means of an agent-based simulation. The result is a digital twin of the current Internet Computer, to be exploited to drive future design and development optimizations, investigate its performance, and evaluate the resilience of this distributed system to some security attacks. Preliminary performance measurements on the digital twin and simulation scalability results are collected and discussed. The study also confirms that agent-based simulation is a prominent simulation strategy to develop digital twins of complex distributed systems