Existing fail-stop signature schemes, classified according to risk bearers

Note that according to the description above, the entities of courts and recipients do not send any messages in the initialization of existing fail-stop signature schemes with special risk bearers they only receive messages that are broadcast by the entities of the signer and the risk bearers. 

The second service property in which existing fail-stop signature schemes differ is the dependence of authentication on the recipients (see Section 5.2.10). This classification is independent of that according to risk bearers. However, the cases 

A signature is received from the recipient s entity and tested with the same algorithm test that entities of recipients use in authentication.  

If the signature does not pass this test, the court s entity outputs acc = FALSE and stops. Otherwise, it forwards the signature to the signer s entity. 

If it receives an answer from the signer s entity, it uses an algorithm verify to verify that the answer is a valid proof of forgery. If yes, the output is acc = broken otherwise acc = TRUE. 

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Figure 6.2. Existing fail-stop signature schemes, classified according to risk bearers...

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