Physical One-Way Functions
Ravikanth Pappu,*
Ben Recht,
Jason Taylor,
Neil Gershenfeld
Modern cryptographic practice rests on the use of
one-way functions, which are easy to evaluate but difficult to invert.
Unfortunately, commonly used one-way functions are either based on
unproven conjectures or have known vulnerabilities. We show that
instead of relying on number theory, the mesoscopic physics of
coherent transport through a disordered medium can be used to
allocate and authenticate unique identifiers by physically reducing the
medium's microstructure to a fixed-length string of binary digits.
These physical one-way functions are inexpensive to fabricate,
prohibitively difficult to duplicate, admit no compact mathematical
representation, and are intrinsically tamper-resistant. We provide an
authentication protocol based on the enormous address space that is a
principal characteristic of physical one-way functions.
Center for Bits and Atoms, The MIT Media Labs, 20 Ames Street,
Cambridge, MA 02139, USA.
*
Present address: ThingMagic, One Broadway, 14th Floor,
Cambridge, MA 02142, USA.
To whom correspondence should be addressed. E-mail:
ravi{at}thingmagic.com
