A SetRegularKey transaction assigns, changes, or removes the regular key pair associated with an account.
You can protect your account by assigning a regular key pair to it and using it instead of the master key pair to sign transactions whenever possible. If your regular key pair is compromised, but your master key pair is not, you can use a SetRegularKey transaction to regain control of your account.
RegularKey
String
AccountID
(Optional) A base-58-encoded [Address][] that indicates the regular key pair to be assigned to the account. If omitted, removes any existing regular key pair from the account. Must not match the master key pair for the address.
For more information about regular and master key pairs, see Cryptographic Keys.
For a tutorial on assigning a regular key pair to an account, see Working with a Regular Key Pair.
For even greater security, you can use multi-signing, but multi-signing requires additional XAH for the [transaction cost][] and reserve.