Matching Items (5)
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- All Subjects: blockchain
- Creators: Zhao, Ming
Description
Blockchain scalability is one of the issues that concerns its current adopters. The current popular blockchains have initially been designed with imperfections that in- troduce fundamental bottlenecks which limit their ability to have a higher throughput and a lower latency.
One of the major bottlenecks for existing blockchain technologies is fast block propagation. A faster block propagation enables a miner to reach a majority of the network within a time constraint and therefore leading to a lower orphan rate and better profitability. In order to attain a throughput that could compete with the current state of the art transaction processing, while also keeping the block intervals same as today, a 24.3 Gigabyte block will be required every 10 minutes with an average transaction size of 500 bytes, which translates to 48600000 transactions every 10 minutes or about 81000 transactions per second.
In order to synchronize such large blocks faster across the network while maintain- ing consensus by keeping the orphan rate below 50%, the thesis proposes to aggregate partial block data from multiple nodes using digital fountain codes. The advantages of using a fountain code is that all connected peers can send part of data in an encoded form. When the receiving peer has enough data, it then decodes the information to reconstruct the block. Along with them sending only part information, the data can be relayed over UDP, instead of TCP, improving upon the speed of propagation in the current blockchains. Fountain codes applied in this research are Raptor codes, which allow construction of infinite decoding symbols. The research, when applied to blockchains, increases success rate of block delivery on decode failures.
One of the major bottlenecks for existing blockchain technologies is fast block propagation. A faster block propagation enables a miner to reach a majority of the network within a time constraint and therefore leading to a lower orphan rate and better profitability. In order to attain a throughput that could compete with the current state of the art transaction processing, while also keeping the block intervals same as today, a 24.3 Gigabyte block will be required every 10 minutes with an average transaction size of 500 bytes, which translates to 48600000 transactions every 10 minutes or about 81000 transactions per second.
In order to synchronize such large blocks faster across the network while maintain- ing consensus by keeping the orphan rate below 50%, the thesis proposes to aggregate partial block data from multiple nodes using digital fountain codes. The advantages of using a fountain code is that all connected peers can send part of data in an encoded form. When the receiving peer has enough data, it then decodes the information to reconstruct the block. Along with them sending only part information, the data can be relayed over UDP, instead of TCP, improving upon the speed of propagation in the current blockchains. Fountain codes applied in this research are Raptor codes, which allow construction of infinite decoding symbols. The research, when applied to blockchains, increases success rate of block delivery on decode failures.
ContributorsChawla, Nakul (Author) / Boscovic, Dragan (Thesis advisor) / Candan, Kasim S (Thesis advisor) / Zhao, Ming (Committee member) / Arizona State University (Publisher)
Created2018
Description
The interaction between England and Scotland is complicated and continually changing. Scottish writer Sir Walter Scott examines this long-standing relationship through his various writings. Scott conveys a presence that is both acutely aware of the damages enacted upon Scotland by various English political efforts, and sensitive to the delicate relationship that the two regions had begun to form during his lifetime. Through a critical analysis of Scott's novel, Rob Roy, one can see the various strategies Scott used to balance the need to address prior controversies within the relationship, and the petition to move beyond the prior conflict and develop a mutual understanding of each culture. Through this, Scott is able to regenerate a sense of Scottish nationalism for his people, and encourage improved relations within the British Isles.
ContributorsChotena, Chelsea (Author) / Facinelli, Diane (Thesis director) / Foy, Joseph (Committee member) / White, Julianne (Committee member) / Barrett, The Honors College (Contributor)
Created2013-05
Description
Blockchain technology enables peer-to-peer transactions through the elimination of the need for a centralized entity governing consensus. Rather than having a centralized database, the data is distributed across multiple computers which enables crash fault tolerance as well as makes the system difficult to tamper with due to a distributed consensus algorithm.
In this research, the potential of blockchain technology to manage energy transactions is examined. The energy production landscape is being reshaped by distributed energy resources (DERs): photo-voltaic panels, electric vehicles, smart appliances, and battery storage. Distributed energy sources such as microgrids, household solar installations, community solar installations, and plug-in hybrid vehicles enable energy consumers to act as providers of energy themselves, hence acting as 'prosumers' of energy.
Blockchain Technology facilitates managing the transactions between involved prosumers using 'Smart Contracts' by tokenizing energy into assets. Better utilization of grid assets lowers costs and also presents the opportunity to buy energy at a reasonable price while staying connected with the utility company. This technology acts as a backbone for 2 models applicable to transactional energy marketplace viz. 'Real-Time Energy Marketplace' and 'Energy Futures'. In the first model, the prosumers are given a choice to bid for a price for energy within a stipulated period of time, while the Utility Company acts as an operating entity. In the second model, the marketplace is more liberal, where the utility company is not involved as an operator. The Utility company facilitates infrastructure and manages accounts for all users, but does not endorse or govern transactions related to energy bidding. These smart contracts are not time bounded and can be suspended by the utility during periods of network instability.
In this research, the potential of blockchain technology to manage energy transactions is examined. The energy production landscape is being reshaped by distributed energy resources (DERs): photo-voltaic panels, electric vehicles, smart appliances, and battery storage. Distributed energy sources such as microgrids, household solar installations, community solar installations, and plug-in hybrid vehicles enable energy consumers to act as providers of energy themselves, hence acting as 'prosumers' of energy.
Blockchain Technology facilitates managing the transactions between involved prosumers using 'Smart Contracts' by tokenizing energy into assets. Better utilization of grid assets lowers costs and also presents the opportunity to buy energy at a reasonable price while staying connected with the utility company. This technology acts as a backbone for 2 models applicable to transactional energy marketplace viz. 'Real-Time Energy Marketplace' and 'Energy Futures'. In the first model, the prosumers are given a choice to bid for a price for energy within a stipulated period of time, while the Utility Company acts as an operating entity. In the second model, the marketplace is more liberal, where the utility company is not involved as an operator. The Utility company facilitates infrastructure and manages accounts for all users, but does not endorse or govern transactions related to energy bidding. These smart contracts are not time bounded and can be suspended by the utility during periods of network instability.
ContributorsSadaye, Raj Anil (Author) / Candan, Kasim S (Thesis advisor) / Boscovic, Dragan (Committee member) / Zhao, Ming (Committee member) / Arizona State University (Publisher)
Created2019
Description
All modern multiplayer games are administered by having players connect to a remote server which is used to provide the ground truth for game state and player actions. This use of a central server provides a simple and intuitive way to administer game servers but also provides a single point of failure, as each server must be able to process all actions coming in and make a decision on whether the action is allowed or not, and how to update the game state accordingly. In cases where the server is under significant load, either from a very popular game release or from a deliberate attack, the game slows down or completely crashes. When there is a server action backlog, this can allow malicious actors to perform previously impossible actions. By instead using a decentralized platform, we can build a robust system that allows playing games through a P2P manner, filling in the need for central servers with consensus algorithms that provide the security on the part of a central authority. This project aims to show that a decentralized solution can be used to create a transparent, fully playable game of Monopoly with complex features that would be more scalable, reliable, and cost-effective compared to a centralized solution; meaning that games could be produced that costs pennies to publish and modify, taking seconds to propagate changes globally, and most importantly, cost nothing for upkeep. The codebase is available here: https://github.com/SirNeural/monopoly
ContributorsXu, Yun Hui (Author) / Boscovic, Dragan (Thesis director) / Foy, Joseph (Committee member) / Computer Science and Engineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
Proxy digital signatures are a subset of proxy cryptography that enable a peer, as a proxy delegator, to delegate signing privileges to another trusted peer, who becomes a proxy signer. The proxy signer then signs authorized transactions routed to it from the proxy delegator, to then send to the intended third party on their behalf. This has great applications for computer networks where certain devices lack sufficient computational power to secure themselves and may rely on trusted and computationally more powerful peers, particularly within edge and fog networks. Although there are multiple proxy digital signature schemas that are circulated within cryptography-centric research papers, a practical software implementation has yet to be created. In this paper we describe Mengde Signatures: the first practical software implementation of proxy digital signatures. We expound upon the current architecture and process for how proxy signatures are implemented and function in a software engineering context. Although applicable to many different types of networks, we showcase the application of Mengde Signatures on an open source Proof-Of-Work Blockchain.
ContributorsMendoza, Francis (Author) / Boscovic, Dragan (Thesis director) / Zhao, Ming (Committee member) / Computer Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12