backup provider

provider which holds the backup of the service/program (e.g. GNU Taler Wallet), for which we want to have the possibility to recover the masterkey.

escrow provider

provider which stores the backup of the masterkey and the corresponding policies for key recovery and/or one or more keyshare(s).

truth

'ground truth' (e.g. security question, e-mail address, phone number, picture) which is specified by the client and used by the key provider to challenge the client to authorize himself

(Escrow)Method

method which is used to authorize the client to get the key share from the escrow provider

(Decryption)Policy

specification of how to decrypt the encrypted masterkey backup

key share

partial key of the key needed to decrypt the masterkey backup of the corresponding policy.