How it works?

The COINPLUS SOLO products materialize digital private keys on one or more physical supports. They allow the safe keeping of crypto-asset such as Bitcoin, Ripple, Litecoin, Ethereum (as well as all the ERC20/EIP20 tokens)

1. General description

The physical supports developed by COINPLUS are available in two versions: the ‘SOLO’ version, simple, secure and durable support, and in 'SOLO PRO' version, multiple support with the 2 out of 3 signatures rule for optimal governance, while being safe from loss, fraud, theft or destruction of any of the supports. Two forms are possible for 'Solo' and 'Solo Pro': Solo Bars, bars made of steel or precious metals, and Solo Cards, plastic cards in a credit card format. COINPLUS do not possess the private keys related to your SOLO, therefore the loss, the theft or the destruction of your SOLO implies the loss of the associated crypto-assets.

2. How to charge your SOLO?

The COINPLUS SOLO products are sold without any crypto-asset. You must transfer the Bitcoin, Ethereum or any other crypto assets by yourself on the address displayed on the COINPLUS SOLO. In order to do that, if you do not already possess crypto asset, you can exchange your fiat currency (EUR, USD, etc.) on a regulated crypto exchange. After the purchase of crypto-assets you will be able to withdraw them from the exchange. The exchange will ask you to fill in the crypto assets’ address on which you want to withdraw your coins or tokens. During this step, you should enter the address display on your SOLO. After the withdraw approval and execution, you will be able to see the corresponding transaction on the blockchain of the selected crypto-asset.

The addresses of Bitcoin, Ripple, Litecoin, Bitcoin Cash have embedded protection against incorrect inputs, which means that if one of the characters that you entered is not valid, the transaction won’t be send to the network. The Ethereum addresses have as well such mechanism but only when you type your address with upper and lower case. Therefore, it is always recommended to type Ethereum addresses following the case to activate the error detection mechanism.

3. How is it produced?

The SOLO products stand out from other physical wallets in the creation process (global patent pending). For the other wallets, the user of the wallet is required to put his full trust into the creator of the support because the creator will have access to the full private key of the wallet. The COINPLUS solution is to involve two companies for the creation process. Each company generates, engraves and hides a secret on the COINPLUS SOLO bar or card. It means that none of the two company have access to the two secrets.

The main issue is to generate a public address from the two secrets without having access to both. This problem is solvable because all the current crypto assets are based on Elliptic Curve Cryptography (ECC) which allows the computation of specific arithmetic operation on encrypted data. The two companies can exchange the equivalent of the public keys of corresponding to the secrets and compute a common public key without the need to possess the private key.

The process developed by COINPLUS guaranties that none of the two companies involved has access to the full private key of the SOLO. The full private key is only computed at the redemption time when the user unveiled the secrets.

4. How to redeem your crypto-assets.

To transfer crypto-asset from the address of your SOLO to another crypto-asset address you need to reveal the two secrets hidden on you SOLO. In combination with the android or iOS COINPLUS application, you will be able to recompute your private key. This private key can be imported in a software wallet and will be used by the wallet to create and sign a transaction from your SOLO address to the address of crypto-asset of your choice. Many wallet support the import of private key, for example, for Bitcoin: bitcoin-core or Electrum, for Ethereum: metamask, geth, for Litecoin: litecoin-core, electrum-litecoin.

The private key can also be recomputed on a computer using the COINPLUS software to recompute the keys. This version is open-source and available on github. Be aware that recomputing a private key on an unsecure machine exposes you to the loss of your crypto-assets, as only the private key is required to create a valid transaction from your crypto-asset address.

Warning: Ripple Ripple do not support the import of raw private key into their wallet software. COINPLUS has developed a standalone web application to recompute the private key, and create, sign and broadcast a Ripple transaction. This web application, which is a html webpage containing javascript code to perform the cryptographic operations is available on the coinplus_sa github repository. Be advised of phishing attacks which consist in reproducing a visually similar webpage to steal private information. It is recommended to download the html webpage from github and to verify its content and integrity. The sha256 sum (used to verify the integrity of a file) of the solo-redeem-ripple-0.1.1.zip is: 289ae0be881e588c568f367bec4e57916cbf725d5fd6c6003ab497b839a18b06

5. SOLO competitive advantage

The SOLO allows a quick access to a crypto-asset account. It is possible to use the SOLO without any configuration of activation. You have a SOLO, you can simply send crypto-asset to the address displayed. The SOLO is independent from COINPLUS, which means that when you have a SOLO, there is no secret that you need to ask COINPLUS to redeem your crypto-asset, COINPLUS do not store any of the secrets present on the SOLO. Furthermore, COINPLUS has release the software to recompute the private keys from the two secrets under an open source license. The source code is available on github. Finally, the SOLO is very simple because there is no dependence on electronic to store the secrets, it is therefore easily auditable.

6. SOLO versions and forms.

All the SOLO products are based on the combination of two secrets to recompute the private key corresponding to the address of the crypto-asset displayed on the SOLO. Two forms are available for the SOLO products:

The secrets are engraved on the back of the card and protected by two rectangular holograms on which are written “secret 1” and “secret 2”. The card also possess a Near Field Contact (NFC) chip which is used only for convenience to share easily the SOLO address. In this chip, only the address or an URL containing the address is stored. No secrets are stored on the NFC chip. The information in the chip is available as well on the SOLO, therefore, no NFC reader is mandatory to use the COINPLUS SOLO card. There are two version of the SOLO products available: The SOLO PRO is composed of 3 physical supports, all with the same public address, the 'account number'. If you lose or if you are the victim of the theft or the destruction of one of the supports, you do not lose anything because only 2 of the 3 supports are necessary to recover the private key, and thus to have access to the crypto-assets. The benefits that users can derive from the PRO version are: The SOLOs are made in Luxembourg by COINPLUS SA which has been developing over the last 4 years security solutions for cryptographic codes since 2014.