Network Working Group H. Nakajima Internet-Draft Mercari R4D Intended status: Informational M. Kusunoki Expires: January 5, 2022 JDD K. Hida JBA Y. Suga Advanced Security Div, IIJ T. Hayashi Lepidum July 04, 2021 Terminology for Cryptoassets draft-nakajima-crypto-asset-terminology-06 Abstract This document provides terminology used in cryptoassets. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on January 5, 2022. Copyright Notice Copyright (c) 2021 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must Nakajima, et al. Expires January 5, 2022 [Page 1] Internet-Draft Cryptoassets Terminology July 2021 include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Conventions and Definitions . . . . . . . . . . . . . . . . . 2 3. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 2 4. Symbols and abbreviated terms . . . . . . . . . . . . . . . . 7 5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 7.1. Normative References . . . . . . . . . . . . . . . . . . 7 7.2. Informative References . . . . . . . . . . . . . . . . . 7 7.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction Our goal with this document is to improve our understanding on a set of terms which frequently used in documents which related to cryptoassets. Mutual understanding about terminology may help to reach a consensus on issues we're trying to solve. 2. Conventions and Definitions The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 3. Terms and Definitions address: An identifier to represent a public key in a blockchain network. administrator: It is a person who conducts operational maintenance of the system with the authority to change the system settings. From the viewpoint of mutual checking, there are administrators with different authorities depending on the subjects to be managed. See also: operator. asymmetric cryptography: Defined in [RFC4949] as "A modern branch of cryptography (popularly known as "public-key cryptography") in which the algorithms use a pair of keys (a public key and a Nakajima, et al. Expires January 5, 2022 [Page 2] Internet-Draft Cryptoassets Terminology July 2021 private key) and use a different component of the pair for each of two counterpart cryptographic operations (e.g., encryption and decryption, or signature creation and signature verification). " block: A basic unit of the blockchain. A set of transactions on a blockchain which contains a cryptographic hash value of the previous block. blockchain: An ordered series of data chains constructed that attackers cannot alter by cryptographic algorithms. A type of distributed ledger. confirmation: Approval works defined by the consensus algorithm. A status that blocks and transactions in a certain block are approved by miners and users of the blockchain network. consensus: Agreements among nodes in the blockchain network. cryptoasset: A digital representation of values that can be exchanged or transferred digitally, realized by a distributed ledger such as blockchain utilizing cryptography or similar technology. cryptoassets custody service: Business to manage the kind of cryptoassets. cryptoassets custodian: The business entities that operate the cryptoasset custody business. cryptoassets custody system: The information system that responsible for the cryptoasset custody business. cryptoassets exchange: A function for exchanging fiat currencies and cryptoassets, and also exchanging cryptoassets with each other. cryptoassets exchange service provider: A business entity that operates a cryptoasset exchange. deterministic wallet: See: wallet digital signature: Defined in [RFC4949] as "A value computed with a cryptographic algorithm and associated with a data object in such a way that any recipient of the data can use the signature to verify the data's origin and integrity." distributed ledger: A distributed database about cryptoassets with agreed processed. Nakajima, et al. Expires January 5, 2022 [Page 3] Internet-Draft Cryptoassets Terminology July 2021 double spending: Defined in [MasteringBitcoinOnline] as "result of successfully spending some money more than once." fiat currency: Currency which has been established by the government or other authorities. fork: A branch of a ledger. Ledger branching may occur accidentally or by specification changes. accidental fork: A case where a block is accidentally mined at about the same time, and a plurality of chains coexist temporarily. It occurs on a daily basis and converges to the longest chain by re- org. soft fork: A branch caused by specification change of blockchain. It does not affect wallet implementation. hard fork: A branch caused by a specification change without the forward compatibility of the blockchain, which may affect the wallet implementation in addition to the miner. There is a case where a plurality of chains continue to coexist permanently because there is no consensus between developers regarding the case where the majority of nodes stay in the specification change by following the hard fork, we call it split. Examples of typical splits include the division of Ethereum and Ethereum Classic in The DAO case of 2016, the division of Bitcoin and Bitcoin Cash in 2017, and so on. The new coin born by division is called a fork coin. genesis block: An initial block on a blockchain. Genesis block may differ to distinguish chains. hash value: Defined in [RFC4949] as "The output of a hash function." hash rate: Amount of a hash value which node is able to generate per unit of time (generally per second) hierarchy deterministic wallet: See: wallet mining: A process to append a received transaction to a block by validating a transaction with agreed consensus rules such as proof-of-work and proof-of-stake. miner: A network node which contributes its resources to mining. multisignature: Defined in [MasteringBitcoinOnline] as "requiring more than one key to authorize a bitcoin transaction". In this scope, the transaction is not limited to a bitcoin transaction. Nakajima, et al. Expires January 5, 2022 [Page 4] Internet-Draft Cryptoassets Terminology July 2021 node: A device that connects to the blockchain network.Note that the node has a different meaning in the context of expression about the Merkle tree. off-chain transaction: The movement of value outside of the blockchain on-chain transaction: The movement of value on the blockchain operator: It is a person who performs routine tasks based on authority as a normal task. See also: administrator. orphan block: Defined in [MasteringBitcoinOnline] as "Blocks whose parent block has not been processed by the local node, so they can't be fully validated yet." permissioned-chain: A blockchain that only specified members can join the blockchain network. permissionless-chain: See: permissioned-chain public-chain: An open blockchain that anyone can retrieve all of blocks and transactions without special privileges. public key: Defined in [RFC4949] as "The publicly disclosable component of a pair of cryptographic keys used for asymmetric cryptography." private-chain: In contrast with "public-chain", A closed blockchain that only qualified users can access blocks and make transactions. private key: Defined in [RFC4949] as "The secret component of a pair of cryptographic keys used for asymmetric cryptography." proof-of-stake: Defined in [MasteringBitcoinOnline] as "method by which a cryptocurrency blockchain network aims to achieve distributed consensus." proof-of-work: Defined in [MasteringBitcoinOnline] as "A piece of data that requires significant computation to find." reorganization: The convergence into one chain based on a certain consensus from multiple chains that are temporarily branched. reward: Value by the blockchain network which assigned to a miner who successfully validates a transaction. Rules may differ among blockchains and consensus rules. Nakajima, et al. Expires January 5, 2022 [Page 5] Internet-Draft Cryptoassets Terminology July 2021 side-chain: See off-chain smart contract: A guaranteed digital procedure that automatically enforced on a blockchain network. soft fork: See: fork token: 1) Data that represents the amount of cryptoassets like ERC20 specification, 2) Data used in the API as one of the factors with the authentication process. transaction: Defined in [MasteringBitcoinOnline] as "More precisely, a transaction is a signed data structure expressing a transfer of value." incoming transaction: Transfer of cryptoassets from other addresses to one's own address. outgoing transaction: Transfer of cryptoassets from one's own address to other addresses. validation: Checking the accuracy and consistency of given transactions and blocks. Specifically, it is general to verify the integrity of data to be digital-signed and also the integrity of other transactions and blocks. By verifying a transaction repeatedly, it is possible to verify blocks in the transaction. validated: See: validation validator: See: validation wallet: A mechanism that handles a key pair of a public key and a secret key used for transmitting cryptoassets and such a key pair. hot wallet: A wallet that is online connected to the network, the key is activated, and operators can coin out the cryptoassets by automatic processing. cold wallet: A wallet that is disconnected from the network and the key is inactivated. It can not be coined out unless there is an explicit operation by the operator. The frequency of outgoing coins is limited. Between hot wallet and cold wallet, there are various intermediate forms such as a wallet that is online, but requires manual operation at the time of signing a transaction, the wallet that is offline but the operation is automated, and warm wallet. Nakajima, et al. Expires January 5, 2022 [Page 6] Internet-Draft Cryptoassets Terminology July 2021 4. Symbols and abbreviated terms AML Anti-Money Laundering API: Application Programming Interface CFT: Counter Financing of Terrorism DAO: Distributed Autonomous Organization DLT: Distributed Ledger Technologies HD: Hierarchy Deterministic (wallet) PKI: Public Key Infrastructure 5. Security Considerations This document defines terminology for cryptoassets. Therefore, there is no security considerations. 6. IANA Considerations None. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 7.2. Informative References [MasteringBitcoinOnline] Antonopoulos, A., "Mastering Bitcoin", March 2018, . [RFC4949] Shirey, R., "Internet Security Glossary, Version 2", FYI 36, RFC 4949, DOI 10.17487/RFC4949, August 2007, . Nakajima, et al. Expires January 5, 2022 [Page 7] Internet-Draft Cryptoassets Terminology July 2021 7.3. URIs [ref-1] , . Acknowledgments Thanks to members of the Cryptoassets Governance Task Force [ref-1] for help and feedback. Authors' Addresses Hirotaka Nakajima Mercari, Inc. R4D Roppongi Hills Mori Tower 21F 6-10-1 Roppongi Minato, Tokyo 106-6125 JAPAN Email: nunnun@mercari.com Masanori Kusunoki Japan Digital Design, Inc. Nihonbashi Talk Building 3-3-5, Nihonbashi-Hongokucho 103-0021 JAPAN Email: masanori.kusunoki@japan-d2.com Keiichi Hida Japan Blockchain Association Email: hida@jba-web.jp Yuji Suga Advanced Security Division, Internet Initiative Japan Inc. Iidabashi Grand Bloom, 2-10-2 Fujimi Chiyoda, Tokyo 102-0071 JAPAN Email: suga@iij.ad.jp Nakajima, et al. Expires January 5, 2022 [Page 8] Internet-Draft Cryptoassets Terminology July 2021 Tatsuya Hayashi Lepidum Co. Ltd. Email: hayashi@lepidum.co.jp Nakajima, et al. Expires January 5, 2022 [Page 9]