Ex Parte Kumar et al

Patent Trial and Appeal Board

Nov 28, 2018

13951758 (P.T.A.B. Nov. 28, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR
13/951,758 07/26/2013 Nagendra Kumar
131361 7590 11/30/2018
Campbell Stephenson LLP
12001 WEST PARMER LANE
Suite 101
CEDAR PARK, TX 78613
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.
CIS0322US 5626
EXAMINER
YOUNG, STEVER
ART UNIT PAPER NUMBER
2477
NOTIFICATION DATE DELIVERY MODE
11/30/2018 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):
info@cspatents.com
eofficeaction@appcoll.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte NAGENDRA KUMAR, RAJIV ASATI, and
CARLOS M. PIGNATARO
Appeal2017-011843 1
Application 13/951,758
Technology Center 2400
Before JEAN R. HOMERE, JASON V. MORGAN, and
MICHAEL M. BARRY, Administrative Patent Judges.
HOMERE, Administrative Patent Judge.
DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134(a) from a Final Rejection of
claims 1-21. App. Br. 2. We have jurisdiction under 35 U.S.C. § 6(b).
We affirm.
1 Appellants identify the real party in interest as Cisco Technology, Inc.
App. Br. 2.
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Application 13/951,758
Introduction
According to Appellants, the claimed subject matter is directed to a
method and system for reaching the initiator of an echo request message
when the initiator's address is unknown and unreachable by a transit router
in a network ( 100) including a plurality of network segments ( 110( 1 }-(N))
implementing a multiprotocol label switching (MPLS) with various label
switching routing elements (LSRs 120(1 }-(N)) via label switch paths (LSP
125) linking LSP segments (115(1}-(N)), each defining a set of labels.
Spec. ,r,r 1, 16, Fig. 1. In particular, upon receiving an echo request message
at a segment reachability logic module (140) in an LSR element (120) on an
LSP (125) to communicate with an existing MPLS connectivity test logic
module (130) in the same LSR (120), a message receipt detector (205) in the
LSR (120) detects whether a forwarding equivalence class (FEC) stack
within the request message identifying the LSP (120) has changed. Spec.
,r,r 16, 28-32, Fig. 2. In response to detecting that the FEC stack has
changed, a generator (230) in the LSR element (120) generates a new
segment reachability sub-type-length-value (SR sub-TLV) along with an
internet protocol (IP) address and a label allocated to reach the initiator. Id.
,r,r 33, 69.
Representative Claim
Independent claim 1 is representative, and reads as follows:
A method comprising:
receiving an echo request message, wherein the echo
request message comprises an FEC (forwarding equivalence
class) stack that identifies a label switch path (LSP), the echo
request message is received by a label switching routing
element (LSR) on the LSP, the echo request is originated by an
initiator;
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the initiator is unreachable by at least one transit router
on the LSP;
the echo request message comprises a stack of one or
more segment reachability (SR) sub-TLV (type-length-value)
elements, each of which comprises an internet protocol (IP)
address and a label allocated to reach the initiator;
detecting whether the FEC stack changes at the LSR; and
in response to a detection that the FEC stack changes at
the LSR,
generating a new SR sub-TL V element, wherein the SR
sub-TL V element comprises an IP address of the LSR and an
incoming label allocated by the LSR to reach the initiator.
Nadeau
Kompella
Dunbar
Pichumani
Prior Art Relied upon
US 2006/0198321 Al
US 7,936,780 Bl
US 2011/0164501 Al
US 8,339,973 Bl
Rejections on Appeal
Sept. 7, 2006
May 3, 2011
July 7, 2011
Dec. 25, 2012
Claims 1---6, 8-13, and 15-20 stand rejected under 35 U.S.C. § I03(a)
as being unpatentable over the combination Nadeau, Dunbar, and
Pichumani. Final Act. 3-23.
Claims 7, 14, and 21 stand rejected under 35 U.S.C. § I03(a) as being
unpatentable over the combination Nadeau, Dunbar, Pichumani, and
Kompella. Final Act. 23-29.
ANALYSIS
We consider Appellants' arguments as they are presented in the
Appeal Brief, 2 pages 5-10, and the Reply Brief, 3 pages 2-13. We have
2 Rather than reiterate all the arguments of Appellants and all the Examiner's
findings/conclusions, we refer to the Appeal Brief (filed May 15, 2017)
("App. Br."), the Final Action from which the appeal is taken (mailed
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Application 13/951,758
reviewed the Examiner's rejection in light of Appellants' arguments. We
are unpersuaded by Appellants' contentions. We adopt as our own the
findings and reasons set forth in the Final Action and the Examiner's
Answer in response to Appellants' Appeal Brief. See Final Act. 2-30; Ans.
2-34. However, we highlight and address specific arguments and findings
for emphasis as follows.
Appellants argue the proposed combination of Nadeau, Dunbar, and
Pichumani does not teach or suggest an echo request message comprising an
FEC stack that identifies a label switch path. App. Br. 5-7. In particular,
Appellants argue the Examiner's finding that Nadeau's disclosure of a ping
and stack of nodes does not teach the claimed echo request message and
FEC stack, respectively. Id. at 6-7 (citing Nadeau ,r 5). According to
Appellants, because Nadeau' s disclosure distinguishes a node identity from
FEC, Nadeau's "stack of node identities" cannot be equated with the
claimed "FEC stack." Id.
This argument is not persuasive. Nadeau discloses an autonomous
system border router (ASBR) for identifying an originating node in an
MPLS environment. Nadeau, Abstr. In particular, Nadeau discloses
maintaining the identity of each node along the path of a destination node
being pinged so as to enable the destination node to employ the stored
identity as a set of return path routing information to send an
acknowledgment or return response to the originating node. Id. ,r 15.
December 2, 2016) ("Final Act."), and the Answer (mailed July 26, 2017)
("Ans.") for the respective details.
3 We note arguments presented in the Reply Brief (filed September 26,
201 7) ("Reply Br.") are a mere regurgitation of the arguments previously
submitted in the Appeal Brief.
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Further, Nadeau discloses that the ping message may be used to trace the
path taken by the LSP. Id. ,r 11. We agree with the Examiner that because
Nadeau' s ping message from the originating node to a destination node
includes an identified path through which packets are forwarded to deliver
the message to the destination node, as well as to return a response to the
originating node, the disclosed ping message /response teaches the claimed
echo request message. Id. ,r 35; Ans. 3--4. More particularly, we agree with
the Examiner that Nadeau's disclosure of an "FEC" as a "specific label"
representing "a group of flows with the same traffic-engineering
requirements" for IP packets along an LSP teaches the claimed "FEC stack"
identifying a label switch path (LSP). Ans. 30-31 ( citing Nadeau ,r 5). That
is, because the disclosed "FEC" and the claimed "FEC stack" both serve the
purpose of identifying a path through which a message is routed in the node
network, they are functional equivalents.
Further, Appellants argue the proposed combination of references
does not teach or suggest "detecting whether the FEC stack changes at the
LSR." App. Br. 8. According to Appellants, irrespective of whether Nadeau
teaches determining changes (i.e., failures, faults) along the path, such
changes are not detected at the LSR. Id. This argument is not persuasive.
As correctly noted by the Examiner, Nadeau discloses examining the path at
each node to determine whether a detected change/fault in the path occurred
at that particular node. Ans. 31-32 (citing Nadeau ,r 48).
Furthermore, Appellants argue that the proposed combination of
references does not teach or suggest upon determining that changes are
based on impairment in the path, generating a new segment reachability
(SR) sub-TLV in response to detecting that the FEC stack changes at the
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LSR. App. Br. 8-9. According to Appellants, irrespective of whether
Dunbar teaches or suggests determining that changes are based on
impairment in the path, Dunbar does not teach detecting FEC stack changes.
Id. at 9. This argument is not persuasive because it is tantamount to an
individual attack against the references. One cannot show non-obviousness
by attacking the references individually where the rejections are based on
combinations of references. In re Merck & Co., 800 F.2d 1091, 1097 (Fed.
Cir. 1986); see also In re Keller, 642 F.2d 413,425 (CCPA 1981). In this
case, the Examiner relies upon Nadeau ( as discussed above) for detecting
that the FEC stack changes occurred at the LSR. Further, the Examiner
relies upon Dunbar for teaching generating a new segment reachability (SR)
sub-TL V when changes are determined based on impairment on the path.
Ans. 4--5 (citing Dunbar ,r,r 34--48); Dunbar ,r 32. We therefore agree with
the Examiner that the combination of Nadeau and Dunbar teaches or
suggests generating a new segment reachability in response to detecting that
the FEC stack changes at the LSR. Id.
Additionally, Appellants argue the proposed combination of
references does not teach or suggest
an echo request that comprises stack of one or more segment
reachability (SR) elements, each of which comprises an IP
address and a label allocated to reach the initiator, and
generating a new SR element that comprises an IP address of
the LSR and an incoming label allocated by the LSR to reach
the initiator.
App. Br. 9-10. In particular, Appellants argue that Pichumani's disclosure
of a traceroute message comprising stack of response blocks including
incoming/ outgoing IP address information does not teach the claimed IP
addresses and labels. Id. at 10. This argument is not persuasive because it is
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tantamount to an attack against the references individually, as opposed to the
combination thereof. Nadeau discloses placing IP traffic on a defined path
through the network. Nadeau ,r 4. Further, Pichumani discloses adding an
IP header with an IP destination address in an mtrace message between an
originating node and a destination node. Pichumani 13:5-10, 14:19-26. We
agree with the Examiner that the cited Pichumani teaching would
complement the Nadeau-Dunbar combination to help remedy a determined
path impairment between an originating node and a destination node in
response to detecting that FEC stack changes at the LSR as required by the
claim. Ans. 33-34.
Further, we find the Examiner's proposed combination of the cited
teachings of Nadeau, Dunbar, and Pichumani is no more than a simple
arrangement of old elements with each performing the same function it had
been known to perform, yielding no more than one would expect from such
an arrangement. KSR Int'! Co. v. Teleflex Inc., 550 U.S. 398,416 (2007).
The ordinarily skilled artisan, being "a person of ordinary creativity, not an
automaton," would be able to fit the teachings of the cited references
together like pieces of a puzzle to predictably result in a system for
overcoming packets reachability challenges encountered by an echo request
message between an originating node and a destination node in response to
detecting FEC stack changes at the LSR. Id. at 420-21. Because Appellants
have not demonstrated that the Examiner's proffered combination would
have been "uniquely challenging or difficult for one of ordinary skill in the
art," we agree with the Examiner that the proposed modification would have
been within the purview of the ordinarily skilled artisan. Leapfrog Enters.,
Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007) (citing KSR,
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550 U.S. at 418). Consequently, we are satisfied on the record before us that
the Examiner has established by a preponderance of the evidence that the
combination of Nadeau, Dunbar, and Pichumani renders claim 1
unpatentable. Accordingly, we are not persuaded of error in the Examiner's
obviousness rejection of claim 1.
Regarding the rejection of claims 2-21, because Appellants have
either not presented separate patentability arguments or have reiterated
substantially the same arguments as those previously discussed for
patentability of claim 1 above, those claims fall therewith. See 37 C.F.R.
§ 4I.37(c)(l)(iv) (2016).
DECISION
For the above reasons, we affirm the Examiner's rejections of claims
1-21.
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
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