Introduction to multisignature concept

Stellar Network uses signatures as authorization. Transactions always need authorization from at least one public key in order to be considered valid.

Typically transactions only involve operations on a single account. For example, if account A wants to send lumens to account B, only account A needs to authorize the transaction.

Transaction signatures are created by cryptographically signing the transaction object contents with a secret key.  

A transaction with an attached signature is considered to have authorization from that public key or Stellar wallet.

In two cases, a transaction may need more than one signature:

- If the transaction has operations that affect more than one wallet, it will need authorization from every wallet in question.

- A transaction will also need additional signatures if the wallet associated with the transaction has multiple signers. 

That is where the multisignature comes in.

Multisignature (or “multisig”) concept presumes that an account requires two or more secret key signatures before allowing a transaction to occur on the account.

For example, two people want to have a joint account so any transaction made from that account first requires both parties to agree and sign them before it can be submitted.

This increases the security of the account, as long as the two or more secret keys are stored separately.

Transactions on the Stellar Network can include one or more operations.

Each operation falls under a specific threshold category: low, medium, or high. Each threshold defines the combined amount of signature weight an operation needs in order to succeed.

Each account can set its own threshold values. By default, all threshold levels are set to 0, and the master key is set to weight 1.

For the sake of simplicity of use and additional security, at the time of multisig setup, LOBSTR currently sets identical values for all threshold categories and increases them evenly with the addition of new signers.

Be careful and use caution when changing your account's thresholds in other services as this may lead to a permanent block of your account and a loss of your funds!

For all Stellar wallets, the private key that corresponds to its public key is called the master key.

Each master key can be assigned a weight also referred to as the signature weight of that account.

Each signer account also has its own signature weight.

If you are using LOBSTR Vault paired with LOBSTR Wallet or StellarTerm, signature weights of signer keys are the same as the weight of the master key of the primary account.

For the multisig-enabled account, all operations like payments, adding trustlines, updating weights, and others will require two or more signatures - one from your account and one or more additional signatures from your signers.

That is where you will need LOBSTR Vault app.