Ex Parte Cheung et al

Board of Patent Appeals and Interferences

Mar 28, 2012

10414575 (B.P.A.I. Mar. 28, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte FRANCIS CHEUNG, JASON MONROE, KEVIN PATARIU,
IUE-SHUENN CHEN, CYNTHIA DANG,
and MARK TAYLOR CORE
____________

Appeal 2009-013316
Application 10/414,575
Technology Center 2400
____________

Before MAHSHID D. SAADAT, ALLEN R. MacDONALD,
and MARC S. HOFF, Administrative Patent Judges.

SAADAT, Administrative Patent Judge.

DECISION ON APPEAL

Appellants appeal under 35 U.S.C. § 134(a) from the final rejection of
claims 1-30, which are all the claims pending in this application. We have
jurisdiction under 35 U.S.C. § 6(b).
We affirm.
Appeal 2009-013316
Application 10/414,575

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STATEMENT OF THE CASE
Appellants’ invention relates to methods and systems for data
encryption and decryption within a chip using encryption and decryption
keys stored within the chip (see Spec. ¶¶ [07] – [08]).
Claim 1 is illustrative of the invention and reads as follows:
1. A method for encrypting and decrypting data, the
method comprising:
encrypting within a chip, data received from a first external
device coupled to a first bus;
transferring said encrypted data to a second external device
coupled to a second bus;
controlling internally to said chip said transferring;
receiving of encrypted data from said second external device
coupled to said second bus;
controlling internally to said chip said receiving;
decrypting said received encrypted data; and
transferring said decrypted data to said first external device
coupled to said first bus, wherein said encrypting and decrypting
utilizes one or more keys stored within said chip.
Rejection
Claims 1-5, 11-15, and 21-25 stand rejected under 35 U.S.C. § 103(a)
as being unpatentable over Jones (US 5,623,637) and Takahashi (US
5,825,878).
1

Appellants’ Contentions
With respect to independent claims 1, 11, and 21, Appellants contend
that the cited portions of Jones, in columns 1 and 2, indicate that the
passwords and encryption/decryption keys are stored “in a SmartCard that is

1
Separate patentability was not argued for the remaining claims rejected
under § 103 on various combinations including Jones and Takahashi (App.
Br. 15-16).

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separate from the IC that performs the encryption/decryption process” (App.
Br. 8). Appellants further contend that Takahashi, on the other hand, stores
“the encryption/decryption key on the same IC that performs the
encryption/decryption” (id.). Appellants conclude that:
modifying Jones in view of Takahashi would render Jones
unsatisfactory for its intended purpose (e.g., using a separate
SmartCard in accordance with the invention description at col.
1, lines 61-64, and col. 2, lines 5-9 and 30-57 of Jones).
Modifying Jones in view of Takahashi would also change the
principle of operation of Jones since Jones’
encryption/decryption processing is based on using an external
card for storing the encryption/decryption keys, as clearly
explained with regard to FIGS. 1 and 3 of Jones.
(App. Br. 9).
With respect to claims 2-5, 12-15, 22-25, 9, 19, and 29, Appellants
rely on the same reasons stated for the patentability of their base claims and
further assert that Jones does not disclose the recited features of these claims
and Takahashi fails to overcome those deficiencies (see App. Br. 10-14).

ANALYSIS
We have reviewed the Examiner’s rejection in light of Appellants’
contentions that the Examiner has erred. We disagree with Appellants’
conclusions. We adopt as our own the findings and reasons set forth by the
Examiner in the action from which this appeal is taken and the reasons set
forth by the Examiner in the Examiner’s Answer (see Ans. 9-13) in response
to Appellants’ Appeal Brief. However, we highlight and address specific
findings and arguments regarding claim 1 for emphasis as follows.
We note that the Examiner properly relies on Takahashi for teaching a
method of encryption and decryption where one or more keys stored within
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the chip is used for encrypting and decrypting data. See Takahashi, Fig. 1
(the encryption core 20 included in the chip 10), col. 5, ll. 34-50. We
specifically agree with the Examiner’s reasoning that it would have been
obvious to modify Jones with the teachings of Takahashi to store the
encryption/decryption keys within the chip, instead of fetching the keys from
the SmartCard, in order to benefit from a secure memory management that is
also adaptable to other systems (Ans. 5 and 10). In other words, while Jones
provides a tamper-proof storage arrangement by storing the key in the chip
(see Jones, col. 2, ll. 5-9 and 30-57), storing the encryption/decryption keys
in the chip provides additional advantages associated with flexibility in
modifying the processor core and protection from external probing when the
keys are clear from the microprocessor core (see Takahashi, col. 1, ll. 21-27
and 59-67). Therefore, contrary to Appellants’ assertion (App. Br. 9, Reply
Br. 5) that the proposed combination would render Jones unsatisfactory for
its intended purpose or change the principle of operation of Jones, storing
the encryption/decryption keys in the chip is actually a tradeoff to benefit
from the different advantages described in Takahashi.

CONCLUSIONS
1. On the record before us, because the references are properly
combinable , the Examiner did not err in rejecting independent claims 1, 11,
and 21 as obvious over Jones and Takahashi.
2. For the same reasons stated above and based on the Examiner’s
findings with respect to dependent claims 2-5, 12-15, 22-25, 9, 19, and 29,
the Examiner did not err in rejecting the dependent claims.
3. Claims 1-30 are not patentable.
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DECISION
The Examiner’s decision rejecting claims 1-30 is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED

ELD