Possible Benefits of Fail-Stop Security

The possible benefits of a fail-stop signature scheme used as a dual signature scheme have already been discussed in Section 6.2.1. Hence this section concentrates on the advantages of fail-stop security that cannot be achieved by a combination of schemes with ordinary and dual security. 

Of course, selecting risk bearers arbitrarily only works for financial risks (and even there, only to a certain extent). In a large-scale application in the real world, the fail-stop property would make individuals safe from a strong risk, but still leave them with a smaller risk, such as higher insurance premiums or having to use handwritten signatures again. 

On the other hand, one should not neglect that one non-financial risk is completely averted in a system with fail-stop security Nobody can wrongly be branded as a cheater or as quarrelsome. If a ciyptologic assumption is broken, it may be much better that the losses are distributed equally and everybody knows that this is due to a common disaster, than that some signers (or recipients) are made responsible while everybody else believes that they were the ones who tried to cheat. 

As in the previous section, one can regard the last point and the psychologic aspects of the first one as the most important arguments, because they concern the more likely case that the system is not broken — if one really expected the system to be broken, one had better refrain from using it in the first place (unless in parallel with other schemes). 

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