Multi-signing in the XAG Ledger is a method of authorizing transactions for the XAG Ledger by using a combination of multiple secret keys. You can have any combination of authorization methods enabled for your address, including multi-signing, a master key pair, and a regular key pair. (The only requirement is that at least one method must be enabled.)

Benefits of multi-signing include:

  • You can require keys from different devices, so that a malicious actor must compromise multiple machines to send transactions on your behalf.
  • You can share custody of an address between multiple people, each of whom only has one of several keys necessary to send transactions from that address.
  • You can delegate the power to send transactions from your address to a group of people, who can control your address if you are unavailable or unable to sign normally.
  • ... and more.

Signer Lists

Before you can multi-sign, you must create a list of which addresses can sign for you.

The SignerListSet transaction defines which addresses can authorize transactions from your address. You can include up to 8 addresses in a SignerList. You can control how many signatures are needed, in which combinations, by using the quorum and weight values of the SignerList.

Sending Multi-Signed Transactions

To successfully submit a multi-signed transaction, you must do all of the following:

  • The address sending the transaction (specified in the Account field) must own a SignerList in the ledger.
  • The transaction must include the SigningPubKey field as an empty string.
  • The transaction must include a Signers field containing an array of signatures.
  • The signatures present in the Signers array must match signers defined in the SignerList.
  • For the provided signatures, the total weight associated with those signers must be equal or greater than the quorum for the SignerList.
  • The transaction cost (specified in the Fee field) must be at least (N+1) times the normal transaction cost, where N is the number of signatures provided.
  • All fields of the transaction must be defined before collecting signatures. You cannot auto-fill any fields.
  • If presented in binary form, the Signers array must be sorted based on the numeric value of the signer addresses, with the lowest value first. (If submitted as JSON, the submit_multisigned method handles this automatically.)