元宇宙中区块链的应用与展望

doi:10.11959/j.issn.2096-109x.2022045

摘要/Abstract

摘要：

元宇宙是虚拟数字世界与真实物理世界无缝融合的新生态，近来引发了各界的广泛关注。区块链、人工智能、虚拟现实/增强现实及传感技术、移动通信及泛在计算等各种新型互联网技术愈发成熟，使元宇宙的进一步发展成为可能。关于元宇宙的研究主要涉及产业项目、基础设施、关键技术、隐私安全等方面，这些研究虽然涉及区块链技术，但未具体指出区块链应用于元宇宙的优势及具体应用方式。区块链技术不仅可以为元宇宙提供开放自由的去中心化环境，而且可以为其提供公平合理的数字资产分配机制。主要从区块链赋能元宇宙中数字身份和数字资产管理的角度出发，分析了元宇宙的发展历程和特征，讨论了元宇宙发展所需核心技术及面临的挑战。同时研究了区块链的关键技术，并从区块链的本质特征及与其他技术融合优势两个方面对区块链应用于元宇宙做可行性分析。进一步提出元宇宙生态体系架构，重点详细分析了基于区块链的自我主权身份管理模型、区块链-非同质化通证（NFT，non-fungible token）工作流程及其在元宇宙中的应用。结合区块链和元宇宙的最新研究进展，从基础设施、通信和计算资源管理机制、监管与隐私保护以及区块链可扩展和互操作性4个方面指出区块链应用于元宇宙将面临的挑战和未来的研究方向。

关键词: 元宇宙, 区块链, 非同质化通证, 数字身份, 去中心化

Abstract:

The metaverse is a new ecology that seamlessly integrates the virtual digital world and the real physical world, and has recently attracted widespread attention from all walks of life.With the maturity of various new IT technologies such as blockchain technology, artificial intelligence technology, VR/AR and sensing technology, mobile communication technology and ubiquitous computing technology, the further development of the Metaverse is possible.At present, research on the Metaverse mainly involves industrial projects, infrastructure, key technologies, privacy and security, etc.Although blockchain technology is covered in these studies, the specific points about the advantages of blockchain applied to the Metaverse are still lacked.Blockchain technology can not only provide an open and free decentralized environment for the Metaverse, but also act as a fair and reasonable digital asset distribution mechanism.The digital identity and digital asset management in the Metaverse empowered by blockchain was studied.The development process and characteristics of the Metaverse were analyzed.And the core technologies and challenges faced by the development of the Metaverse were discussed.Meanwhile, the key technologies of the blockchain were studied, and the feasibility of applying the blockchain to the Metaverse was analyzed from two aspects: the essential characteristics of the blockchain and the advantages of other technology integration.The Metaverse ecosystem architecture was further proposed, and the blockchain-based self-sovereign identity management model, blockchain-NFT workflow and its application in the Metaverse were analyzed in detail.Furthermore, combining the latest research progress of blockchain and the Metaverse, it was pointed out that the application of blockchain to the Metaverse will be from four aspects: infrastructure, communication and computing resource management mechanisms, regulation and privacy protection, and blockchain scalability and interoperability.Then the related challenges ahead and future research directions were presented at last.

Key words: Metaverse, blockchain, NFT, digital identity, decentralization

中图分类号:

TP393

宋晓玲, 刘勇, 董景楠, 黄勇飞. 元宇宙中区块链的应用与展望[J]. 网络与信息安全学报, 2022, 8(4): 45-65.

Xiaoling SONG, Yong LIU, Jingnan DONG, Yongfei HUANG. Application and prospect of blockchain in Metaverse[J]. Chinese Journal of Network and Information Security, 2022, 8(4): 45-65.

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特征	描述
超时空化	元宇宙是虚拟和现实世界的无缝融合且两个世界间相互平行又相互影响，使用户交互摆脱现实世界的约束
去中心化	元宇宙中的节点交互不需要通过某个特定中心节点做认证，并且每个节点都存储系统中所有交互数据的副本
自由开放	元宇宙中的用户可以自由塑造自己的身份角色、创造产品并可以自由活动、交易和制定规则
沉浸交互	元宇宙中的沉浸交互体现在沉浸式情境与沉浸式活动两方面，交互式情境更丰富感知、交互活动更真实

类型	项目名称	区块链	AR/VR	人工智能
智慧城市	Metaverse Seoul	√	√	√
	Barbados Metaverse Embassy	√	√	√
娱乐	AltspaceVR	√	√	√
	Decentraland	√	√	√
教育	Xirang	√	√	√
办公	Horizon WorkroomsMicrosoft Mesh	√√	√√	√√
医疗	Telemedicine	√	√	√

名称	链式结构	有向无环图结构
区块形式	区块以链式结构连接，每个区块中包含多笔交易	区块以有向无环图结构连接，每个区块中只包含一笔交易
交易速度	每次只能增加一个区块的数据量，交易速度较慢	支持局部处理和并行结算，交易的人越多交易越频繁，速度越快
共识机制	共识机制是为了选举出打包交易的节点，如工作量证明、权益证明等，共识过程有矿工参与	共识机制不是为了选举打包交易的节点，每笔交易由节点自身处理，共识过程无矿工参与
扩展性和改进方案	可扩展性弱，改进方案：增加区块大小、支持，链外通道、节点分级或分片	可扩展性强，扩展方案：使用耦合网络和事务验证，但前提是用户先要处理自己的交易
抗量子攻击	加密算法容易被量子计算机攻击	使用了抗量子攻击的密码算法不易被攻破
交易费用	需要消耗的资源费用高	资源费用消耗很低

类别	详细	代表算法
证明类	通过证明节点具有的某种特定能力（如算力、权益）较高的方式选出记账节点	PoW^[48]、PoS^[49]、PoSV^[50]、PoB^[51]等
选举类	通过“投票选举”的方式选出获得一半以上选票的节点作为记账节点	DPoS^[52]、PBFT^[53]、DBFT^[54]等
随机类	根据某种随机方式（如抽签）选出记账节点	Ouroboros^[55]、PoET^[56]、Algorand^[57]等
混合类	多种共识算法结合使用选出记账节点	PoA^[58]等
注：权益流通证明（PoSV，proof of stake velocity）；燃烧证明（PoB，proof of burn）；委托权益证明（DPoS，delegated proof of stake）；实用拜占庭容错（PBFT，practical Byzantine fault tolerance）；授权拜占庭容错（DBFT，democratic Byzantine fault tolerance）；时间流逝证明（PoET， proof of elapsed-time）；活动证明（PoA，proof of activity）。

名称	去中心化程度	可扩展性	灵活性	共识机制	透明性可修改性	可追踪性
公有链	完全去中心化	弱	弱	证明类共识算法（PoW、PoS）	全透明不可修改	可追踪
联盟链	半去中心化	较好	较好	传统共识算法（Raft、PBFT等）	不透明部分可修改	可追踪
私有链	中心化	一般	一般	传统共识算法（Raft、PBFT等）	半透明可修改	部分可追踪