Internet Engineering Task Force A. Sardon Internet-Draft Swisscom Intended status: Informational T. Hardjono Expires: May 3, 2021 MIT October 30, 2020 Blockchain Gateways: Use-Cases draft-sardon-blockchain-gateways-usecases-00 Abstract In the past five years there has been a growing interest in using blockchains and DLT systems as a means to create a new mechanism to issue, distribute and manage virtual assets. However, as DLT systems consisting of peer-to-peer (P2P) network of nodes increase in number, there is an increasing need to interconnect these networks to permit virtual assets to flow into and out of them. This document captures a number of use-cases driving the need for interoperability between DLT systems. 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 May 3, 2021. Copyright Notice Copyright (c) 2020 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 Sardon & Hardjono Expires May 3, 2021 [Page 1] Internet-Draft Blockchain Gateways: Use-Cases October 2020 to this document. Code Components extracted from this document must 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. Use-Case: CBDC interoperability . . . . . . . . . . . . . . . 2 3. Use-Case: Application and Data Portability . . . . . . . . . 3 4. Use-Case: Interconnection of Supply-Chains . . . . . . . . . 3 5. References . . . . . . . . . . . . . . . . . . . . . . . . . 3 5.1. Normative References . . . . . . . . . . . . . . . . . . 4 5.2. Informative References . . . . . . . . . . . . . . . . . 4 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction In the past five years there has been a growing interest in using blockchains and DLT systems as a means to create a new mechanism to issue, distribute and manage virtual assets. However, as DLT systems consisting of peer-to-peer (P2P) network of nodes increase in number, there is an increasing need to interconnect these networks to permit virtual assets to flow into and out of them. This document captures a number of use-cases driving the need for interoperability between DLT systems. 2. Use-Case: CBDC interoperability A Central Bank Digital Currency (CBDC) is a digital version of the sovereign currency within a nation. The CBDC is distinct from other types of digital currencies because (a) its sole issuer is a central bank, and (b) like paper sovereign currencies the issuance of a CBDC represents a claim that the holder has upon the central bank. Many central banks are considering the use of DLT systems for CBDCs. For example, the Monetary Authority of Singapore (MAS) and the Bank of Canada (BOC) have been experimenting with private blockchains and have been exploring methods used to settle CBDCs (see project Ubin and Jasper) [MAS19]. Since different central banks might be using different private DLT systems, interoperability of these systems will be crucial for facilitating cross-border payments. The MAS and BOC have carried out a joint pilot project in 2019 to evaluate how transactions between a Quorum-based and Corda-based systems can be performed [MAS19]. While their HTLC based proof-of- Sardon & Hardjono Expires May 3, 2021 [Page 2] Internet-Draft Blockchain Gateways: Use-Cases October 2020 concept with direct node-to-node connectivity was conducted successfully, they point out that such a network model may have poor resiliency and suggest testing alternative models, in particular using gateway nodes that would act as service nodes for the network participants. 3. Use-Case: Application and Data Portability Portability has been described as a desirable property for applications on private blockchains and DLT systems [SKS18]. For example, applications with poor portability may suffer from vendor lock-in effects, potentially preventing users to benefit from better middleware platforms. Moreover, regulations like the GDPR even explicitly require data portability. For private blockchains, where the network members may be subject to such regulations, interoperability shall be encouraged [STOA19]. The use case would be to migrate either the application (e.g. a token smart contract) and/or the associated state (e.g. token balances) from one private blockchain to another. 4. Use-Case: Interconnection of Supply-Chains Blockchains and DLT systems are currently being deployed for augmenting the supply-chains of good and services [Scot19]. The notion of a shared ledger has significant appeal among the participants of a supply-chain network (e.g. suppliers, vendors, buyers, etc.) because: (i) it permits all participants with equal visibility into the state of the supply/demand of goods; (ii) permitting suppliers (e.g. manufacturers) to increase their efficiency in maintaining the supply of goods in warehouses, leading to the freeing-up of capital, and (iii) allowing participants to improve the tracking of deliveries and payments settlements. A key challenge for of a supply-chain network based on DLT systems is its ability to interoperate with another supply-chain network. Interoperability across blockchains and DLT systems allows a participant (e.g. manufacturer, buyer) to participate at a single end-point in the network, while giving them access to all other blockchains that are connected. Without interoperability, the participant would need to join each and every supply-chain DLT, something that is cumbersome, costly and does not scale. 5. References Sardon & Hardjono Expires May 3, 2021 [Page 3] Internet-Draft Blockchain Gateways: Use-Cases October 2020 5.1. 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, . 5.2. Informative References [MAS19] MAS, "Jasper-Ubin Design Paper, Enabling Cross-Border High Value Transfer Using Distributed Ledger Technologies, Monetary Authority of Singapore.", May 2019, . [Scot19] Scott, T., "TradeLens: How IBM and Maersk Are Sharing Blockchain to Build a Global Trade Platform. IBM Report", November 2018, . [SKS18] Shudo, K., Kanda, R., and R. Saito, "Towards Application Portability on Blockchains, Proc. IEEE HotICN 2018", August 2018, . [STOA19] STOA, "EU STOA, Blockchain and the GDPR: Can distributed ledgers be squared with European data protection law?, EU European Parliamentary Research Service, STOA, PE 634.445.", July 2019, . Authors' Addresses Aetienne Sardon Swisscom Email: Aetienne.Sardon@swisscom.com Thomas Hardjono MIT Email: hardjono@mit.edu Sardon & Hardjono Expires May 3, 2021 [Page 4]