If P != NP Then Some Strongly Noninvertible Functions Are Invertible
نویسندگان
چکیده
Rabi, Rivest, and Sherman alter the standard notion of noninvertibility to a new notion they call strong noninvertibility, and show—via explicit cryptographic protocols for secret-key agreement ([RS93,RS97] attribute this to Rivest and Sherman) and digital signatures [RS93,RS97]—that strongly noninvertible functions would be very useful components in protocol design. Their definition of strong noninvertibility has a small twist (“respecting the argument given”) that is needed to ensure cryptographic usefulness. In this paper, we show that this small twist has a large, unexpected consequence: Unless P = NP, some strongly noninvertible functions are invertible. Topic: Computational and Structural Complexity.
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 362 شماره
صفحات -
تاریخ انتشار 2001