NICIRA, INC.

Patent Trials and Appeals Board

Sep 20, 2021

2020004616 (P.T.A.B. Sep. 20, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
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
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/375,142 12/11/2016 Liwen WU N370 4285
152591 7590 09/20/2021
Ren-Sheng International
(VMWARE-NICIRA)
7F, No. 57, Sec. 2, DunHua S. Road
Taipei, 106
TAIWAN
EXAMINER
KEEHN, RICHARD G
ART UNIT PAPER NUMBER
2456
NOTIFICATION DATE DELIVERY MODE
09/20/2021 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):
filing@suipconsulting.com
gsu@suipconsulting.com
ipadmin@vmware.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte LIWEN WU, JIA YU, XINHUA HONG,
RONGHUA ZHANG, and DAVID LEROY
Appeal 2020-004616
Application 15/375,142
Technology Center 2400

Before ALLEN R. MacDONALD, CAROLYN D. THOMAS, and
AMBER L. HAGY, Administrative Patent Judges.

HAGY, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 1–24, which are all of the pending
claims. See Final Act. 1–2; Appeal Br. 1. We have jurisdiction under
35 U.S.C. § 6(b).
We affirm.

1 “Appellant” herein refers to “applicant” as defined in 37 C.F.R.
§ 1.42. Appellant identifies the real parties in interest as VMware, Inc., and
Nicira, Inc. Appeal Br. 3.
Appeal 2020-004616
Application 15/375,142

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CLAIMED SUBJECT MATTER
The subject matter of the present application pertains to methods for
handling failure at a logical router in a network. Spec., Abs. By way of
background, Appellant’s Specification describes “virtualized computing
environment[s],” in which “virtual machines running different operating
systems may be supported by the same physical machine (e.g., referred to as
a ‘host’).” Id. ¶ 2. Appellant’s Specification also describes “network
virtualization,” in which “logical networks may be provisioned, changed,
stored, deleted and restored programmatically without having to reconfigure
the underlying physical hardware.” Id. ¶ 3. Such logical networks may
include “[l]ogical routers,” which, “similar to physical router[s],” are
“susceptible to failure.” Id. According to Appellant, the present application
purport to describe and claim:
addressing a failure at a logical router that includes a distributed
router (DR), an active service router (SR), and a standby SR
(which are “routing components”). Prior to a failure of the
active SR, the DR learns the path information provided by the
active SR and its standby SR. In response to detection of the
failure of the active SR, the DR assigns the standby SR to be
the new active SR and sends packets to the newly active SR
based on the previously learned path information.
Appeal Br. 5.
Claims 1, 9, and 17 are independent. Claim 1, reproduced below with
the disputed limitation italicized, is representative:
1. A method for a first routing component to handle
failure at a logical router in a first network, wherein the logical
router includes the first routing component, an active second
routing component and a standby second routing component,
and the method comprises:
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Application 15/375,142

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prior to a failure at the active second routing component,
learning first path information associated with a first path
provided by the active second routing component, and second
path information associated with a second path provided by the
standby second routing component, wherein the first path and
second path connect the first routing component to a second
network;
in response to detecting a first egress packet that is
destined for the second network, sending the first egress packet
to the active second routing component over the first path based
on the first path information; and
in response to detecting the failure at the active second
routing component,
assigning the standby second routing component to
be a new active second routing component; and
in response to detecting a second egress packet that
is destined for the second network, sending the second
egress packet to the new active second routing
component over the second path based on the second
path information.
Appeal Br. 15 (Claims App.).
REFERENCES
The Examiner relies on the following references:
Name2 Reference Date
Thang US 2002/0167898 A1 Nov. 14, 2002
Sigoure US 2015/0381386 A1 Dec. 31, 2015
Zhang US 2016/0226762 A1 Aug. 4, 2016

2 All references are cited using the first-named inventor.
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Application 15/375,142

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REJECTIONS
Claims 1–5, 7–13, 15–21, 23, and 24 stand rejected under 35 U.S.C.
§ 103 as obvious over the combined teachings of Zhang and Thang.
Final Act. 4–7.
Claims 6, 14, and 22 stand rejected under 35 U.S.C. § 103 as obvious
over the combined teachings of Zhang, Thang, and Sigoure. Final Act. 7–8.
OPINION
We have considered Appellant’s arguments (Appeal Br. 9–13; Reply
Br. 3–7) in light of the Examiner’s findings and explanations (Final Act. 4–
8; Ans. 3–8). For the reasons set forth below, we are not persuaded of
Examiner error in the rejections of the pending claims, and we, therefore,
sustain the Examiner’s rejections.
Appellant argues only claim 1 with particularity, and argues the
remaining claims are patentable for the reasons expressed as to claim 1.
See Appeal Br. 13. Therefore, based on Appellant’s arguments, we decide
the appeal of claims 1–24 based on claim 1 alone. See 37 C.F.R.
§ 41.37(c)(1)(iv) (2019).
The Examiner relies on a combination of Zhang and Thang as
teaching or suggesting the subject matter of claim 1. Final Act. 3–5.
Appellant argues the Examiner’s findings are in error with regard to the
disputed limitation, which recites “prior to a failure at the active second
routing component, learning first path information associated with a first
path provided by the active second routing component, and second path
information associated with a second path provided by the standby second
routing component . . . .” Appeal Br. 9. In particular, Appellant contends
“the recited ‘second path information associated with a second path’ is
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required in claim 1 to be both: (1) provided by the standby second routing
component, and (2) learned prior to a failure at the active second routing
component.” Id. Appellant argues the Examiner “failed to identify where
such recitations are taught or suggested by the cited references.” Id.
With regard to the first part of the limitation identified, Appellant
contends the Examiner’s reliance on Zhang is in error because, when Zhang
provides path information, it is not until after Zhang’s standby component
has transitioned to an active component; therefore, in Zhang, the second path
information is not provided “by the standby second routing component.”
Appeal Br. 10 (emphasis added). With regard to the second part of the
limitation identified, Appellant contends “Thang merely describe[s]
restoring an IP network in the event of a communication failure between two
routers,” and “is completely silent with respect to whether any of the two
routers is ‘active’ or ‘standby,’ let alone ‘an active second routing
component’ and ‘a standby second routing component.’” Id. According to
Appellant, although Thang describes learning alternate paths between
routing components prior to a failure of one or more components, it does not
disclose that such components are “standby” or “active.” Id.
The Examiner responds that Appellant is attacking references
individually without addressing the combination as applied by the Examiner.
Ans. 5. In particular, the Examiner points out that the Examiner relies on
Zhang as teaching a path information exchange between routers and for
teaching active and standby routers. Id. at 4–5 (citing Zhang ¶¶ 5, 7).
Zhang is not relied on as teaching learning path information prior to failure;
rather, for that limitation, the Examiner relies on Thang. Id. at 4–7 (citing
Thang ¶ 81). And, in turn, the Examiner does not rely on Thang as
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disclosing routers being “active” or “standby,” but rather relies on Zhang for
such teaching. See id.
We are not persuaded of Examiner error in these findings. As the
Examiner notes, and we agree, Appellant does not address the Examiner’s
findings regarding the combination of Zhang and Thang. It is well
established that one cannot show nonobviousness by attacking references
individually where the rejections are based on combinations of references.
See In re Keller, 642 F.2d 413, 425 (CCPA 1981); In re Merck & Co., 800
F.2d 1091 (Fed. Cir. 1986).
The Examiner finds, and we agree, that Zhang teaches active and
standby routing components. Final Act. 3 (citing Zhang ¶¶ 1, 3–5, 7, 257);
Ans. 4–5 (citing Zhang ¶¶ 5, 7). The Examiner also finds, and we agree, that
Zhang:
discloses learning first path information associated with a first
path provided by the active second routing component, and
second path information associated with a second path provided
by the standby second routing component, as cited above, but
does not disclose learning the paths prior to a failure at the
active second routing component.
Id. at 4. With regard to learning path information prior to failure, the
Examiner finds, and we agree, that Thang discloses “learning alternate paths
between routing components prior to a failure of one or more components
causing a communication failure.” Id. (citing Thang claim 1 and ¶ 81).
We are also unpersuaded by Appellants’ arguments that the Examiner
has failed to establish the requisite motivation to combine the cited
references. See Appeal Br. 11–12. In particular, Appellant argues that the
Examiner “has failed to establish why a person of ordinary skill in the art
would modify Zhang and/or would combine Zhang with Thang,” because
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Zhang discloses sending route information (via gratuitous address resolution
protocol (“GARP”) messages) after failure. Id. at 12.
We recognize the Examiner must articulate “reasoning with some
rational underpinning to support the legal conclusion of obviousness.” In re
Kahn, 441 F.3d 977, 988 (Fed. Cir. 2006). However, the Examiner’s
reasoning need not appear in, or be suggested by, one or more of the
references on which the Examiner relies. Instead, a reason to combine
teachings from the prior art “may be found in explicit or implicit teachings
within the references themselves, from the ordinary knowledge of those
skilled in the art, or from the nature of the problem to be solved.” WMS
Gaming Inc. v. Int’l Game Tech., 184 F.3d 1339, 1355 (Fed. Cir. 1999)
(citing In re Rouffet, 149 F.3d 1350, 1355 (Fed. Cir. 1998)). “Under the
correct [obviousness] analysis, any need or problem known in the field of
endeavor at the time of invention and addressed by the patent can provide a
reason for combining the elements in the manner claimed.” KSR Int’l Co. v.
Teleflex Inc., 550 U.S. 398, 420 (2007).
In the instant appeal, the Examiner has provided a rationale
supporting motivation by a person of ordinary skill in the art to achieve the
claimed subject matter. Final Act. 5. Specifically, the Examiner finds:
[i]t would have been obvious to one of ordinary skill in the art
to combine learning the paths prior to a failure at the active
second routing component, taught by Thang et al., with learning
first path information associated with a first path provided by
the active second routing component, and second path
information associated with a second path provided by the
standby second routing component, taught by Zhang et al., in
order to be prepared for a communication failure.
Id. (citing Thang ¶ 81).
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Appellant has not provided persuasive evidence or line of reasoning
explaining why such rationale is erroneous or why a person of ordinary skill
in the art would not have reached the conclusions reached by the Examiner.
See DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick
Co., 464 F.3d 1356, 1368 (Fed. Cir. 2006) (“[T]he proper question is
whether the ordinary artisan possesses knowledge and skills rendering him
capable of combining the prior art references.”). At most, Appellant argues
that the invention claimed in the instant application eliminates the need to
send GARP messages after a failure occurs, whereas Zhang relies on sending
such messages, and hence combining Zhang with Thang would “change the
principle of operation of Zhang.” Appeal Br. 12. In response, the Examiner
finds that combining Thang with Zhang to achieve the claimed invention
would not change the principle of operation of Zhang because the claimed
invention does not preclude sending GARP messages after failure:
[L]earning alternate paths in advance, taught [by] Thang, would
not eliminate the need to announce that a failure occurred. No
principal operation is being changed, as alleged by Appellant.
It just means that after the failure is announced, the alternate
path(s) would have already been predetermined. Doing so
would make the system better prepared to respond more quickly
to a failure, and hence provides motivation to combine the
feature of advanced alternate route determination of Thang,
with routing failure recovery of Zhang.
Ans. 7–8.
Appellant has not persuaded us that the Examiner failed to articulate a
sufficient rationale for combining the teachings of the cited references. We
agree that nothing the claims precludes sending GARP messages, and we
further agree that combining the teachings of Zhang with Thang would not
change the principle of operation of Zhang.
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Application 15/375,142

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For the foregoing reasons, we are not persuaded of Examiner error in
the rejection of claim 1, and we, therefore, sustain that rejection, along with
the rejection of independent claims 9 and 17, and all of the dependent
claims, which are all argued collectively with claim 1. See Appeal Br. 13.
CONCLUSION
We sustain the Examiner’s obviousness rejections of claims 1–24.

DECISION SUMMARY
In summary:
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
1–5, 7–
13, 15–
21, 23, 24
103 Zhang, Thang 1–5, 7–13,
15–21, 23,
24

6, 14, 22 103 Zhang, Thang, Sigoure 6, 14, 22
Overall
Outcome:
1–24

TIME PERIOD FOR RESPONSE

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv).
AFFIRMED