Network Working Group H. Nakajima
Internet-Draft Mercari, Inc.
Intended status: Informational June 7, 2018
Expires: December 9, 2018

General Security Considerations for Crypto Assets Exchange


This document discusses the threat, risk, and controls on the followings; Online system of crypto assets exchange that provides the exchange service to its customer (consumers and trade partners); assets information (including the private key of the crypto assets) that the online system of a crypto assets exchange manages; Social impact that can arise from the discrepancy in the security measures that are implemented in the online system of a crypto assets exchange.

This document is applicable to the crypto assets exchanges that manages the private key that corresponds to the crypto assets. It includes the organizations that outsources the key management to another organization. In such a case, the certain recommendations applies to those outsourcers.

Status of This Memo

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This Internet-Draft will expire on December 9, 2018.

Copyright Notice

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Table of Contents

1. Introduction

TODO Introduction

2. Scope of this document

In this document, crypto assets exchange operators which hold a private key of crypto assets.

3. 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.

4. Terminology

5. Basic description of a model online system of a crypto assets exchange

5.1. General

In this clause, a model online system of a crypto assets exchange that is used to explain the concepts and provisions in this document are explained.

5.2. A basic model of online system of a crypto assets exchange and its functional components

Followings are the basic model of a crypto assets exchange that this document deals with.

5.3. The flow leading to the sending of the transaction

5.4. Types of keys that are used for signature and encryption

5.4.1. Type of keys

5.4.2. A flow for the key generation and the key usage

5.4.3. On the usage of multiple keys

5.4.4. On the suspension of keys

5.5. On the characteristics of crypto assets on Blockchain and distributed ledger technologies

5.5.1. General

5.5.2. The importance of the private key used for signing

5.5.3. Diversity of implementations On the cryptographic algorithms used by crypto assets On the possibility of the forking of the Blockchain Rollback by reorganization The treatment of the forked crypto assets

5.5.4. Risk on the unapproved transactions General The handling of the unapproved transactions Transaction failures caused by the vulnerabilities of the implementation or the specification of the crypto assets

6. Basic objectives for the security management of crypto assets exchanges

7. Approaches to basic security controls

8. Sector specific security management controls for crypto assets exchanges

8.1. General

8.2. On the direction of the information security management

8.3. On the controls for key recovery

8.4. On the controls against theft and leakage of the private key for signing

8.5. On the illegal operation of the private key for signing

8.6. On the illegal operation against the assets data

8.7. On the user authentication

8.8. On the withdrawal of the coins

8.9. On the transfer of the crypto assets to an unused address

9. Remaining issues

10. Security Considerations

TODO Security

11. IANA Considerations

This document has no IANA actions.

12. 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.

Appendix A. Contributors

Author's Address

Hirotaka Nakajima Mercari, Inc. EMail: