Ex Parte Guillen-Hernandez et al

Patent Trials and Appeals Board

Mar 22, 2019

14531243 - (D) (P.T.A.B. Mar. 22, 2019)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
14/531,243 11/03/2014
23494 7590 03/26/2019
TEXAS INSTRUMENTS IN CORPORA TED
PO BOX 655474, MIS 3999
DALLAS, TX 75265
FIRST NAMED INVENTOR
Oscar Miguel Guillen-Hernandez
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
TI-75051 5415
EXAMINER
CAREY, FORREST L
ART UNIT PAPER NUMBER
2491
NOTIFICATION DATE DELIVERY MODE
03/26/2019 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
uspto@ti.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte OSCAR MIGUEL GUILLEN-HERNANDEZ
and RALF BREDERLOW
Appeal2018-005937
Application 14/531,243
Technology Center 2400
Before DENISE M. POTHIER, JASON J. CHUNG, and
LINZY T. McCARTNEY, Administrative Patent Judges.
POTHIER, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants 1,2 appeal under 35 U.S.C. § 134(a) from the Examiner's
rejection of claims 1--4, 6, 7, 9, 10, and 18-29. See generally Appeal Br.
Claims 5, 8, and 11-17 have been canceled. Final Act. 2. We have
jurisdiction under 35 U.S.C. § 6(b). We affirm.
1 Throughout this opinion, we refer to the Final Action (Final Act.) mailed
May 26, 2017, the Appeal Brief (Appeal Br.) filed October 11, 2017, and the
Examiner's Answer (Ans.) mailed February 22, 2018. No Reply Brief has
been filed.
2 Appellants identify the real party in interest as Texas Instruments
Incorporated. Appeal Br. 1.
Appeal2018-005937
Application 14/531,243
Invention
Appellants' "embodiments relate generally to plaintext analysis in
secure systems using encryption to detect, react to and/ or interdict side
channel attacks." Spec. ,r 2. In side channel attacks, attackers use physical
characteristics ( e.g., power consumption or changes) to determine secret
encryption code values, which can include a secret key. Id. ,r,r 3--4. An
attacker attempts to infer a secret value key by observing physical
characteristics, and if the key value is obtained, can access encrypted data
using the same secret key. Id. ,r 3. For example, an attacker can send
plaintext data for encryption and can detect information leakage from the
encryption system to detect the secret key. Id. ,r 4. Appellants' invention
attempts to improve on known countermeasure strategies ( e.g., shielding,
masking, and hiding) against side channel attacks. Id. ,r,r 5-8.
Independent claim 1 exemplifies the claims at issue and reads as
follows:
1. A system including countermeasures for side channel attacks,
compnsmg:
an encryption module coupled to receive plaintext data
for encryption and outputting corresponding ciphertext, the
encryption module performing an encryption algorithm using a
secure key stored in non-volatile memory; and
a plaintext analysis module coupled to receive the
plaintext data received by the encryption module[,] the plaintext
analysis module performing an analysis on the plaintext data
and determining whether the plaintext data correlates to
expected plaintext data, the plaintext analysis module further
having an output for outputting a signal indicating a side
channel attack, responsive to the determining.
Appeal Br. 10 (Claims App'x).
2
Appeal2018-005937
Application 14/531,243
The Examiner relies on the following as evidence of unpatentability:
Buhr
Motoyama
Robertson
Gold
US 2008/0235796 Al
US 2011/0296198 Al
US 2012/0011346 Al
US 2014/0052983 Al
The Rejections
Sept. 25, 2008
Dec. 1, 2011
Jan. 12,2012
Feb.20,2014
Claims 1, 3, 18, 20, 21, 26, and 29 are rejected under 35 U.S.C.
§ I02(a)(l) as anticipated by Motoyama. Final Act. 2-8.
Claims 2, 6, 7, 10, 19, 22, 24, 25, and 28 are rejected under 35 U.S.C.
§ I03(a) as unpatentable over Motoyama and Gold. Id. at 9-15.
Claims 4 and 23 are rejected under 35 U.S.C. § I03(a) as unpatentable
over Motoyama, Gold, and Buhr. Id. at 16-18.
Claims 9 and 27 are rejected under 35 U.S.C. § I03(a) as unpatentable
over Motoyama and Robertson. Id. at 18-19.
THE ANTICIPATION REJECTION
Appellants argue the claims as group (Appeal Br. 5-7), and we select
claim 1 as representative. See 37 C.F.R. § 4I.37(c)(l)(iv). The Examiner
finds Motoyama discloses claim 1 's limitations, including a plaintext
analysis module ( e.g., comparator) determining whether plaintext correlates
to expected plaintext data. Final Act. 3 ( citing Motoyama ,r,r 39--40, 82-90,
96, 101, Fig. 10); Ans. 5-7 (citing Motoyama ,r,r 76-105, Figs. 9-11).
Appellants argue Motoyama fails "correlate plaintext data with
expected plaintext data" as claim 1 requires. Appeal Br. 7. Appellants
contend Motoyama compares encrypted data in register 26 with encrypted
data in register 41. Id. at 5-7 (citing Motoyama ,r,r 93-95, Figs. 10-11).
3
Appeal2018-005937
Application 14/531,243
ISSUE
Under § 102, has the Examiner erred in rejecting claim 1 by finding
Motoyama discloses "a plaintext analysis module ... determining whether
the plaintext data correlates to expected plaintext data"?
ANALYSIS
We begin by construing a key disputed limitation of claim 1,
"plaintext data" and "expected plaintext data." During examination of a
patent application, a claim is given its broadest reasonable construction "in
light of the specification as it would be interpreted by one of ordinary skill in
the art." In re Am. Acad. of Sci. Tech Ctr., 367 F.3d 1359, 1364 (Fed. Cir.
2004) (citation omitted). We presume that claim terms have their ordinary
and customary meaning. See In re Translogic Tech., Inc., 504 F.3d 1249,
1257 (Fed. Cir. 2007).
The Specification defines "plaintext data" as "unencrypted
information" (Spec. ,r 25) but does not define separately "expected plaintext
data" (see Ans. 5). The Specification shows data analysis module 55
analyzing plaintext ( e.g., plaintext data 'm') at both the encryption stage
(Figure 4) and the decryption stage (Figure 5). Id. ,r,r 40-41, Figs. 4--5.
Similarly, Microsoft Computer Dictionary defines "plaintext" as
"[ n ]onencrypted or decrypted text. " 3 In light of the Specification and the
ordinary meaning of "plaintext," we construe "plaintext data" and "expected
plaintext data" to mean respectively unencrypted, non-encrypted, or
decrypted information and expected unencrypted, non-encrypted, or
decrypted information. Based on this understanding, we agree that
3 MICROSOFT® COMPUTER DICTIONARY 407 ( 5th ed. 2002) ( def. 1 ).
4
Appeal2018-005937
Application 14/531,243
Motoyama discloses the recited "plaintext analysis module ... determining
whether the plaintext data correlates to expected plaintext data" in claim 1.
As background, Motoyama discloses a cryptographic processing
technique to resist power analysis and fault attacks. Motoyama ,r 7 6, Figs.
9--11. In this embodiment, the cryptographic circuit (e.g., 15B) includes
encryption circuit 21, decryption circuit 22, selectors 24 and 25, registers 26
and 41, and comparator 42. Id. ,r,r 37-38, 84, Figs. 9--10. Motoyama
teaches comparator 42 compares data held in the registers 26 and 41 and,
when inconsistent, outputs an alarm signal. Id. ,r 88. The crux of the appeal
turns on whether the data compared in comparator 42 is "plaintext data" and
"expected plaintext data" as recited.
Concerning register 26, Motoyama discloses "the same components as
those of FIG. 1 are given the same reference characters" in Figure 9 "thereby
omitting the description thereof." Id. ,r 80. Motoyama discloses in Figure 1
cryptographic circuit module 15 shown in more detail in Figure 2. Id.
,r,r 5---6, Figs. 1-2. Similarly, Motoyama's Figure 9 has cryptographic circuit
module 15B shown in more detail in Figure 10. Id. ,r,r 13-14, Figs. 9-10.
We thus presume the components in Figure 10 having the same reference
characters as Figure 2 operate similarly. See id. ,r,r 5---6, 80.
Motoyama teaches in Figure 2, like Figure 10, an initial value INd is
plain text to be encrypted and selector 25 selects this INd value, which is
stored in register 26, only when processing for initial value INd. Id.
,r,r 39--40, cited in Final Act. 3. Motoyama therefore stores plaintext in
register 26 in at least one instance. But, a value is not stored in register 41
and compared at comparator 42 until CS1 signal is sent. Id. ,r 86, Fig. 10.
According to Motoyama, this signal "is generated based on the timing of
5
Appeal2018-005937
Application 14/531,243
insertion of reverse operation processing" (id.) or a decryption operation (id.
,r 36). Comparator 42 therefore does not compare values in register 26 and
41 until a decryption operation occurs. See id. ,r,r 36, 96. In Figure 11, such
an operation does not occur until t4. Id., Fig. 11.
Motoyama additionally discloses, once the encryption operation or
decryption starts, selector 25 then selects the output of selector 24 (e.g., an
output from the encryption operation) and outputs the result data. Id. ,r 41.
Such result data, described as "intermediate data of the encryption
operation" is held in register 26. Id. The Examiner finds this intermediate
data is the recited "plaintext data" in claim 1 and is compared with other
intermediate data at comparator 42. See Ans. 7 (stating "the input to any
encryption module is considered a plaintext"); see id. at 5-7 ( citing
Motoyama ,r,r 86, 88, 89, 96, 99-101). Specifically, the Examiner
determines "regardless of whether the input data was previously encrypted"
(id. at 6 (emphases omitted)), the input data into an encryption module (e.g.,
sent back to encryption circuit 21) "is considered the plaintext" (id.).
We find this construction unreasonably broad. As stated above, our
construction of "plaintext data" means unencrypted, non-encrypted, or
decrypted data. Motoyama's partially or intermediate encrypted data is still
encrypted data rather than unencrypted or non-encrypted data. However, the
Examiner further explains Motoyama retains data in a register, including
"the original plaintext," during decryption. See Ans. 8-9; see also Final
Act. 3.
As previously discussed, Motoyama describes a decryption operation
"corresponds to a reverse operation of the encryption operation by the
6
Appeal2018-005937
Application 14/531,243
encryption circuit 21." Motoyama ,r 36. Referring to Motoyama's
annotated Figure 11 (Appeal Br. 6) below,
1tt
t{ f
i.§ i.
'
.,
' ,. ··,;, -'" .,,, ···-·:····--.-.,
t,. (· ......... .
:•
~ t··
? ~ \
'l i I(, ( : . . '"i . , . "" . ,
: . ; i : . '
'.:'(t . ~-, tJ' . ;; . i~, -1~~ ,t t.: ·l>~ t~ t;t tH ,,
Motoyama's Annotated Figure 11 Showing Comparator 42's Timing
a decryption or reverse operation occurs at various times, including at t2
(labeled B). Motoyama ,r 15, Fig. 11 (annotated); Appeal Br. 5 (indicating
point A is labeled at t 1 and points B and C are added at t2 and t3
respectively). Thus, in the above scenario, after reverse operation at t2
(point B), the decrypted data (e.g., plaintext) is held in register 41. Id. ,r 86.
Moreover, comparator 42 compares this data at t2 held in register 41 to data
held in register 26 related to the same step ( e.g., those at step 0) because the
values of round registers 31 and 33 will be consistent (e.g., both at the same
step). See id. ,r,r 40, 88-89, 92, Figs. 10-11 (annotated). In the above
example, the data held in registers would be plaintext.
Other reverse operation scenarios can occur, such as at t4 in annotated
Figure 11, after encryption at t3 (labeled C) and comparator 42 compares
unencrypted data at t2 (labeled B) stored in register 41 to unencrypted data
at t4 (not shown) stored in register 26. See id. ,r,r 40, 88-89, 92, 101, Figs.
10-11. Moreover, Motoyama discloses result data held in register 26 can be
7
Appeal2018-005937
Application 14/531,243
"data that is finally ... decrypted" (Motoyama ,r 41 ), such that at some later
time the finally decrypted data in register 26 (e.g., "plaintext data" in claim
1) is compared at comparator 42 to a previously stored data for a step/round
(e.g., decrypted data stored in register 41 at t2 (labeled B) in annotated
Figure 11).
Appellants have not filed a Reply Brief, and the Examiner's findings
in this regard (see Ans. 8-9) are not rebutted. Motoyama thus discloses a
plaintext analysis module "determining whether the plaintext data correlates
to expected plaintext data" as claim 1 recites.
For the above reasons, Appellants have not persuaded us of error in
the rejection of independent claim 1 and claims 3, 18, 20, 21, 26, and 29,
which are not separately argued.
THE OBVIOUSNESS REJECTIONS
Appellants do not argue separately these rejections, contending the
claims under these rejections are allowable because claims 1, 18, and 21 are
allowable. See Appeal Br. 8-9. For reasons similar to those above, we
sustain the rejections of claims 2, 4, 6, 7, 9, 10, 19, 22-25, 27, and 28.
DECISION
We affirm the Examiner's rejection of claims 1, 3, 18, 20, 21, 26, and
29 under§ 102 and claims 2, 4, 6, 7, 9, 10, 19, 22-25, 27, and 28 under
§ 103.
8
Appeal2018-005937
Application 14/531,243
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l )(iv).
AFFIRMED
9
*
*
Notice of References Cited
Document Number
Countiy Cotie-Number-Kind Code
A US-
B US-
c US-
C\ US-!J
E US-
F US-
c; US-
H US-
US-
j US-
K US-
L US-
M US-
Document Number
Country Code-Number-Kind Cotie
N
0
p
Q
R
s
T
Date
MM-YYYY
Date
MM-YYYY
Application/Control Applicant(s)/Patent Under Patent
Appeal No. 2018-005937
14/531,243
Examiner Art Unit
2491
Page 1 of ·1
U.S. PATENT DOCUMENTS
Name CPC Classification US Classification
FOREIGN PATENT DOCUMENTS
Country Name CPC Classification
NON-PATENT DOCUMENTS
* Include as applicable: Author, Tille Date, Publ;sher, Edition or Volume, Pertinent Pages)
u
Microsoft Computer Dictionary 407 (5th ed. 2002)
V
w
X
',<\ copy of tt11s reference 1s not being furr11shed w1m mis Office act1orL (See MPEP § 707.05(a).)
Dates in MM-YYYY tormat are publication dates. Classifications may be US or foreign.
U.S. Patent and Trademark Office
PT0-892 (Rev. 01-2001) Notice of References Cited Part of Paper r~o. 20170303
Microsoft·
i
I .
Microsoft®
om uter . ' .
1c 1onar
Fifth Edition
I
I
j
I
PUBLISHED BY
Microsoft Press
A Division of Microsoft Corporation
One Microsoft Way
Redmond, Washington 98052-6399
Copyright © 2002 by Microsoft Corporation
All rights reserved. No part of the contents of this book may be reproduced or transmitted in any form
or by any means without the written permission of the publisher.
Library of Congress Control Number: 2002019714
Microsoft Press books are available through booksellers and distributors worldwide. For further informa-
tion about international editions, contact your local Microsoft Corporation office or contact Microsoft
Press International directly at fax (425) 936-7329. Visit our Web site at www.microsoft.com/mspress.
Send comments to mspinput@microsoft.com.
Active Desktop, Active Directory, ActiveMovle, ActiveStore, ActiveSync, ActiveX, Authenticode,
BackOffice, BizTalk, ClcarType, Direct3D, DirectAnimation, DirectDraw, Directlnput, DirectMusic,
DirectPlay, DirectShow, DirectSound, DirectX, Entourage, FoxPro, FrontPage, Hotmail, IntelliEye,
IntelliMouse, IntelliSensc, JScript, MapPoint, Microsoft, Microsoft Press, Mobile Explorer, MS-DOS,
MSN, Music Central, NetMeeting, Outlook, PhotoDraw, PowerPoint, SharePoint, UltimateTV, Visio,
Visual Basic, Visual C++, Visual FoxPro, Visual InterDev, Visual J++, Visual SourceSafe, Visual Studio,
Win32, Wln32s, Windows, Windows Media, Windows NT, Xbox are either registered trademarks or
trademarks of Microsoft Corporation in the United States and/or other countries. Other product and
company names mentioned herein may be the trademarks of their respective owners.
The example companies, organizations, products, domain names, e-mail addresses, logos, people, places,
and events depicted herein are fictitious. No association with any real company, organization, product,
domain name, e-mail address, logo, person,. place, or event is intended or should be inferred.
Acquisitions Editor: Alex Blanton
Project Editor: Sandra Haynes
Body Part No. XOS-41929
ixel image
;oft Excel or
or a data-
1 manipulate
1· summorize
of nnalysis.
~nti ng a Piv-
rnrt form.
in 8 100-
1 COJTCC[
that can
ear of l 970
q,reted as
··ough 69 as
·ing.
pot in a rcc-
individu-
c screen by
iito smallest
wctre can
1hics. Sec
ixel
ufpixelr in
:,phic in a
,I bit
:la pixel
cl depth,
i:~ned to
. pixel map
pixel map 11. A clala strncture that describes the pixel
image of a graphic, including such fe3tures as color,
image, resolution, dimensions, slornge .fonmll, and num-
ber of bits usccl to describe each pixel. See also pixel, pixel
illlage.
pJL 11. Sa Printer Job Language.
pJ/NF n. Acronym for,projeqion-join normal form. See
11 ormal form (definition I).
PIWNZIP 11. A shareware utility program that uncom-
presses files compressed by the PKZIP shareware utility
program. PKUNZJP is generally made available with
PKZlP; clisLribulion of PK UNZIP for commercial pur-
poses is nol pennltlcd without obtaining permission from
lts publisher, PK ware, Inc. See a/so PKZTP.
PKZIP n. A widely used shareware utility program for·
compressing l1lcs. Developed by PK ware, Inc., in 1989
and available from a wide variety of sources, PKZ!P can
combine one: or 1nore tiles into a compressed output file
having the exlension .zip. A companion ulil ity program,
PKUNZII', is required lo uncompress the compressed
files. See also PKUNZ!P, slrnreware, utility program. ·
PLA 11. Acronym for programmable logic array. See field-
programmable logic array.
placeholder 11. 1. A clrnrnctcr that masks or hicles another
charncler for security reasons. For example, when a user
types a password, an asterisk is displayed on Lhc screen to
take the place of each character typed. 2. Text or some
other element used in an application as an indicator that
the user should enter in his or her own text.
Plain Old Telephone SeJ'vice 11. See POTS,
plaintext n. 1. Noncncryptecl or decrypted text. See also
decryplion, encryption. 2. A file that is stored as plain
ASCrr dala. Compare ciphertcxt.
plain vanilla adj. Ordinary; Lhe standard version of hard-
ware or sol'Lware without any enlrnnccments. For example,
a plain vanilla modem mighl have data transfer capability
but no fax or voice features.
.plan n. A file in a UNIX user's borne directory that is dis-
played when olhcr users finger that account. Users can
enter information in Lo .plan files al their discretion to pro-
viclc infornrnlio11 in addition to lliat normally displayed by
lhc finger command. See also finger.
platform
planar adj. L In computer graphics, lying within a plane.
2. ln the fabrication of scrniconcluctor materials, maintain~
ing the original flat surface of the silicon wafer throughout
processing, while the chemicals that make up lhc elements
thal control the flow of current are diffused lnlo (and
beneath) the surface.
planar transistor n. A special form of transistor that is
fabricated with all tl1ree elements (collector, emitter, and
base) on a single layer of semiconductor material. Tl1e
structure of a planar transistor perrnils it lo dissipate rela-
lively large amounts of heat, making Lhis design suitable
for power transistors. See the illustration.
Insulating layer
i---------~---· L
Collector
Planar transistor.
plasma display n.. See gas-discharge display.
plastic lec1dless c;hip carrier n. See PLCC.
plastic transistor 11. A transistor produced entirely from
plastic rather than the trndilionaJ silicon. A plastic transis-
tor is llexiblc enough to be embedded in curved surfaces
or folded. Production of plastic transistors begins with a
thin piece ol clear plastic, onto which layers of plastic are
printed or sprayed through a mesh. The result is a light-
weight, tJexible and transparent transistor thal can be nrnn~
ufactured in high volumes for a fraction of the cost of
silicon transistors. The flexibilily and low-cost of plaslic
transistors make tl1em useful in applications from trans-
parenL folclahlc displays lo one-use producl containers. See
also eleclron i c paper.
platen n. The cylinder in most impact printers and type-
writers, around which the paper wraps m1d against which
the print mechanism strikes the paper. The paper bail,' a
spring-loaded bar with small roll em, holds the paper
smoothly against the platen just above the print mechanism.
platform n. l. The foundation teclrnology of a computer
system. Because computers are layered devices composed