Cannazon: Bitcoin Multisig


We strongly advise reading the following chapters and setting up multisignature for Bitcoin payments on your Cannazon account. This will protect you against the possibility of a vendor not responding to a refund and other similar cases. Learn in the next steps all about Bitcoin multignature and how to use it.


Multisignature (Multisig) is a protocol within Bitcoin which lets multiple addresses lock funds into a single transaction wallet. There are two forms of multisig on Cannazon: 2-of-2, which locks funds into place using 2 addresses and 2-of-3 which uses 3 addresses. For either version only 2 addresses are needed to unlock and release the coins. On Cannazon the multisig transactions are setup like this:

  • 2-of-2 multisig escrow: Cannazon Public Key + Vendor Public Key
  • 2-of-3 multisig escrow: Cannazon Public Key + Vendor Public Key + Buyer Public Key

If you have not maintained a public Bitcoin key in your settings, 2-of-2 multisig will be used by default.

Info

We strongly advise to maintain a key to automatically use 2-of-3 multisig as you are not totally dependent on the vendor in the case something goes wrong.


The easiest way is to use coinb.in for this. You will create an address and use the public and private key from it. This address will not be related to your wallet and you will not need it afterwards. You do only need the public and private Bitcoin key for multisignature. Please note that you are also free to use a public and private Bitcoin key e.g. from your Electrum wallet.

  1. Go to coinb.in/#newAddress. You will have to enable JavaScript in your browser to use it. Select “New”  and “Address”.
  2. Click on “Generate”  to generate a new Bitcoin address.
  3. Copy and save the public and private key that is displayed. We recommend using KeePassX as explained here. Do not loose your private key, as you will not be able to access refunded funds otherwise!
  4. Copy and paste the public key to your account settings on Cannazon.

That's it! You will use the private key to a sign transactions once a transaction from Cannazon is provided.

Setup Bitcoin Multisig


There are several ways to sign transactions depending on which Bitcoin client you are using. The easiest way to sign a transaction quickly is also with coinb.in.

  1. Copy the transaction from the order detail page that is already signed by Cannazon.
  2. [Optional] Go to coinb.in/#verify. You will have to enable JavaScript in your browser to use it. Paste the transaction and click “Submit”. This allows you to verify the transaction and double check that your correct address for receiving the coins has been used.
  3. Go to coinb.in/#sign.
  4. Paste the transaction and your private key that belongs to the public key you have used here. Click on “Submit”  to sign the transaction with your key.
  5. Copy the signed transaction.
  6. Next, go to the “Broadcast”  tab, paste the signed transaction from the previous tab into the box and click ‘Submit”.

That's it, the transaction is now broadcasted and the coins were send.

Sign Bitcoin multisig transactions


Normally, you do not have to sign transactions as a buyer. Only signing for a refund or dispute might be needed.