Quantum Attacks and Xaman

A little bit about Quantum attacks

Introduction

This article is meant to answer some basic questions about quantum computing and to explain our view on the future of quantum attacks as they relate to Xaman and the XRP Ledger.

What is a quantum computer?

Theoretically, in the near future, there will be several different types of quantum computers that will be capable of doing certain types computation at very high speeds. Some of those computers will most likely be suitable for analyzing cryptographic algorithms. Those are referred to as CRQC's or “Cryptographically Relevant Quantum Computers”. CRQCs will theoretically be extremely adept at attacking and deciphering real world cryptographic systems.

Which cryptographic systems are at risk of being attacked?

The XRP Ledger uses asymmetric-key algorithms to secure XRPL account. Also referred to as public-key algorithms, asymmetric-key algorithms use paired keys (a public and a private key) in performing their function. The public key is known to all, but the private key is controlled solely by the owner of that key pair. The private key cannot currently be mathematically calculated through the use of the public key even though they are cryptographically related. In theory, CRQC's will be able to calculate the private key based solely on the information contained in the public transactions recorded on the XRPL.

When will a quantum computer be ready to initiate a quantum attack?

Some estimates suggest CRQC's will be viable in about 5 years time. One study suggests that a quantum computer possessing about 4000 qubits of processing power could theoretically crack the cryptography used by Bitcoin. Currently, IBM has a machine with just over 400 qubits of processing power.

How does this apply to the XRP Ledger?

Currently, there is no agreed upon definition of what makes an algorithm quantum resistant.

In theory, a quantum resistant algorithm for the XRP Ledger must be able to:

• resist quantum factoring (See Shor's algorithm)

• resist quantum searching (See Grover's algorithm)

• resist quantum machine learning

When such an algorithm is developed, integrating it into the XRPL should be a straight forward process. (Just as the Ed25519 algorithm was added).

Keep in mind, any new algorithm that is added to the XRPL will need to be supported forever, so while it is a fairly easily process to add additional algorithms, it is not something to be taken lightly. Ideally, the XRPL community will wait as long as safely possible before adding a new one.

What can I currently do to protect my assets?

There are currently two options to options to help protect against quantum attacks until quantum resistant algorithms are implemented on the XRPL:

1. Create a new XRPL account and move your assets to your new account then leave it alone. A CRQC will need an outgoing public transaction to analyze the public key of you account. Once you perform any outgoing transaction on your new account, it will be vulnerable to a quantum attack.

2. Create a new XRPL account and re-key your existing account to point to your new account then disable your master key on your existing account and leave it alone. Once you perform any outgoing transaction on your new re-keyed account, it will be vulnerable to a quantum attack.

Spam is a real issue on the XRPL. In-coming transactions such as spam will not effect your quantum protection. Only outgoing transactions will.