Appeal No. 2000-1330
Application No. 08/972,835
distribution function to provide said cryptographic
key; wherein: said cryptographic key has an
associated first work factor S for a person without
knowledge of said key space distribution function;
and said cryptographic key has an associated second
work factor W < S for a person with knowledge of
said key space distribution function.
Also, we note that the only other independent claim, claim 14,
is in the apparatus format which recites substantially the
same limitations.
Upon our review of Elander, we fail to find that Elander
teaches the above limitations. In column 9, line 39, through
column 10, line 45, Elander discloses that Figure 3 is a block
diagram illustration of two cryptographic systems, A and B,
that communicates CDM keys via a strong key distribution
channel 50 and communicate CDM-masked data via a weakened
privacy channel 60. From the careful reading of Elander, we
find that Elander's system provides a separate weak (CDM) and
a strong (DEA) keys and does not teach a single apparently
strong key that is weak for the government's use only.
Although the Elander's final CDM key is weak, the CDM key K
transmitted in Figure 3 is the strong key. We note that
Appellant is claiming protecting the weak key with a one-way
function, whereas Elander only protects the strong key with a
5
Page: Previous 1 2 3 4 5 6 7 8 9 10 Next
Last modified: November 3, 2007