Ciena Corporation

Patent Trials and Appeals Board

Jul 27, 2021

2020000397 (P.T.A.B. Jul. 27, 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.
14/750,129 06/25/2015 Loudon T. BLAIR 10.2270 2869
22474 7590 07/27/2021
Clements Bernard Walker
4500 Cameron Valley Parkway
Suite 350
Charlotte, NC 28211
EXAMINER
HOUSHMAND, HOOMAN
ART UNIT PAPER NUMBER
2465
NOTIFICATION DATE DELIVERY MODE
07/27/2021 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):
cjones@worldpatents.com
patlaw@worldpatents.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte LOUDON T. BLAIR, JOSEPH BERTHOLD, NIGEL L. BRAGG,
and RAGHURAMAN RANGANATHAN
Appeal 2020-000397
Application 14/750,129
Technology Center 2400
Before MAHSHID D. SAADAT, JUSTIN BUSCH, and
CARL L. SILVERMAN, Administrative Patent Judges.
BUSCH, 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, 3–12, and 14–20. We have
jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

1 We use the term Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies the real party in interest as Ciena
Corporation. Appeal Br. 2.
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Application 14/750,129

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CLAIMED SUBJECT MATTER
Appellant’s disclosure generally “relates to systems and methods for a
distributed data center architecture.” Spec. ¶ 1. More specifically, the
claimed invention relates to systems and methods used to treat two data
centers and a wide area network (WAN) across which the data centers
communicate with each other as a single distributed data center using a
unified label space having an ordered label structure including locally
significant and globally significant labels. See, e.g., Spec. ¶¶ 6, 51. Claim
1, reproduced below, is illustrative of the claimed subject matter:
1. A network element configured to provide a single
distributed data center architecture between at least two data
center locations, the network element comprising:
a plurality of ports and a switch configured to switch
packets between the plurality of ports;
wherein a first port of the plurality of ports is connected to
an intra-data center network of a first data center location and a
second port of the plurality of ports is connected to a second data
center location that is remote from the first data center location
over a Wide Area Network (WAN), and
wherein the intra-data center network of the first data
center location, the WAN, and an intra-data center network of
the second data center location utilize an ordered label structure
between one another to form the single distributed data center
architecture, wherein the ordered label structure is a unified label
space between the intra-data center network of the first data
center location, the WAN, and the intra-data center network of at
least the second data center location,
wherein the ordered label structure comprises a plurality
of layers with a first set of layers being a first label, a second
label, and a third label which are locally significant to the first
data center location and the second data center location such that
the first label, the second label, and the third label are reusable
across the first data center location and the second data center
location, and a second set of layers being a fourth label which is
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globally significant across the single distributed data center
architecture such that the fourth label is unique across the single
distributed data center architecture, and
wherein the first label is between servers, the second label
is between Leaf switches, and the third label is between spine
switches, and wherein the fourth label is between the first data
center location and the second data center location.
REFERENCES
Name Reference Date
Dharwadkar US 2008/0084880 A1 Apr. 10, 2008
Blair US 2013/0259465 A1 Oct. 3, 2013
Kapadia US 2016/0352633 A1 Dec. 1, 2016

REJECTIONS
Claim 20 stands rejected under 35 U.S.C. § 112(b) as indefinite. Final
Act. 7.
Claims 1, 3–12, and 14–20 stand rejected under 35 U.S.C. § 103 as
obvious over Blair, Dharwadkar, and Kapadia. Final Act. 8–29.

ANALYSIS
REJECTION OF CLAIM 20 UNDER 35 U.S.C. § 112(B)
The Examiner rejects claim 20 as indefinite under 35 U.S.C. § 112(b)
because claim 20 allegedly is missing a feature. Final Act. 7; Ans. 3.
Appellant presents no argument regarding this rejection. Appeal Br. 8
(“Also, Claim 20 is rejected under 35 U.S.C. 112(b) for lack of antecedent
basis (not addressed herein).”). Accordingly, we summarily sustain the
rejection of claim 20 under 35 U.S.C. § 112(b).
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REJECTION OF CLAIMS 1, 3–12, AND 14–20 UNDER 35 U.S.C. § 103
Appellant argues the rejection of claims 1, 3–12, and 14–20 as a group
based on claim 1. Appeal Br. 10–14; Reply Br. 1–3. Therefore, we select
independent claim 1 as representative of these claims, which stand rejected
under 35 U.S.C. § 103 as obvious over Blair, Dharwadkar, and Kapadia.
Final Act. 8–29; see 37 C.F.R. § 41.37(c)(1)(iv).
In particular, the Examiner finds Blair discloses Ethernet Private
Local Area Networks (EPLANs) using Optical Transport Network (OTN)
switches and virtual switches providing “low latency, yet multi-point
connectivity between a selective subset of data centers 1702A-1702D across
the WAN” so the disparate data centers can communicate with each other,
which the Examiner finds teaches or suggests a network element that
provides a single distributed data center architecture between at least two
data centers remotely accessed across a WAN. Final Act. 8–9 (quoting Blair
¶ 74). The Examiner finds both Blair and Dharwadkar teach or suggest
using an ordered label structure between the data centers and the WAN to
form the single distributed data center architecture. Final Act. 10 (initially
finding Blair fails to teach an ordered label structure and relying on
Dharwadkar (citing Dharwadkar ¶ 4); Ans. 13 (additionally finding Blair
teaches using the Mutli-Protocol Label Switching (MPLS), which uses an
ordered label structure (citing Blair ¶ 79)). The Examiner finds the proposed
combination—i.e., incorporating the particular ordered label structure
disclosed in Dharwadkar’s into Blair’s general teaching of using MPLS—
results in a system that suggests a unified label space between the data
centers and WAN including the particular sets of labels recited in
representative claim 1. Final Act. 11–13 (citing Blair ¶¶ 74, 96; Dharwadkar
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¶ 4). Finally, the Examiner finds Kapadia discloses the particular
hierarchical data center architecture recited in the claims (i.e., servers, leaf
switches, and spine switches within each data center) and, combined with
Blair and Dharwadkar’s teaching of connecting data centers via EPLANs
using the unified name space implemented with the MPLS ordered label
structure, Blair, Dharwadkar, and Kapadia teach the particularly recited
association between labels and data center nodes (i.e., servers, leaf switches,
and spine switches). Final Act. 12–13 (additionally citing Kapadia, Fig. 2).
An obviousness analysis “need not seek out precise teachings directed
to the specific subject matter of the challenged claim, for a court can take
account of the inferences and creative steps that a person of ordinary skill in
the art would employ.” KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418
(2007). “A person of ordinary skill is also a person of ordinary creativity,
not an automaton.” KSR, 550 U.S. at 421. “The test for obviousness is not
whether the features of a secondary reference may be bodily incorporated
into the structure of the primary reference; . . . [r]ather, the test is what the
combined teachings of the references would have suggested to those of
ordinary skill in the art.” In re Keller, 642 F.2d 413, 425 (CCPA 1981)
(citations omitted). The operative question is “whether the improvement is
more than the predictable use of prior art elements according to their
established functions.” KSR, 550 U.S. at 417.
Appellant presents various arguments that, in sum, generally assert
that the proposed combination would not have been made and, even if the
combination were made, it would not have taught a single distributed
architecture between two data centers connected over a WAN center using a
unified label space having an ordered label structure including locally
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significant and globally significant labels. See Appeal Br. 11–14; Reply
Br. 1–3. Appellant’s assertions that the applied prior art fails to teach
various features fail to consider the combination of the art and the
knowledge of a person of ordinary skill when combining the art.
Accordingly, and for the more detailed reasons discussed below, Appellant’s
arguments do not persuade us that the rejection of the pending claims under
35 U.S.C. § 103 should be reversed.
Among other arguments, Appellant contends that neither Blair nor
Dharwadkar teaches an “ordered label structure” or a “unified label space”
between data centers “to form the single distributed data center
architecture.” Appeal Br. 11; Reply Br. 1–2. In particular, Appellant asserts
that Blair’s EPLANs connecting two data centers across a WAN does not
“form a single distributed data center” or a “unified label space” because
“Blair does not treat the interconnected data centers as a distributed data
center architecture under the same control.” Appeal Br. 11. Appellant
further contends Dharwadkar merely teaches an MPLS label stack, but not
an ordered label structure between data centers to form a single distributed
data center architecture.
As the Examiner correctly notes, see Ans. 10, Blair discloses creating
a network topology of data centers using EPLANs and explicitly discloses
that the “data centers may be (i) owned by a private enterprise, (ii) operated
by a service provider and (iii) . . . communicate between each other.” Blair
¶ 74. Blair further discloses that “the dedicated EPLAN 1704 provides a
way to define private, low latency, yet multi-point connectivity between a
selective subset of data centers 1702A-1702D across the WAN.” Blair ¶ 74.
Blair’s EPLANs includes virtual switches that “are Ethernet service switches
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and can use MPLS.” Blair ¶ 91. Because Blair discloses connecting data
centers with EPLANs to communicate between them over a WAN including
embodiments that use MPLS in Layer 2 (i.e., Ethernet) virtual switches, and
because Dharwadkar discloses that MPLS uses a unified label space having
an ordered label structure, we find that the disclosed EPLANs teach or
suggest connecting at least two data centers over a WAN using “an ordered
label structure between one another to form the single distributed data center
architecture, wherein the ordered label structure is a unified label space,” as
recited in representative claim 1.
Appellant also argues Blair, Dharwadkar, and Kapadia fail to teach
“locally significant” labels, “globally significant” labels, or the details
reciting that particular labels are between particular nodes. Appeal
Br. 11–13; Reply Br. 2–3. Appellant further contends the Examiner’s
rationale for combining Kapadia is insufficient. Appeal Br. 13.
The Examiner finds Appellant’s invention uses MPLS labels inside
MPLS headers and adds a label for each layer of architecture and removes a
label when a packet reaches its destination. Ans. 15–16; see also Spec.
¶¶ 39 (“Also, because all devices (e.g., switches, virtual switches
(vSwitches), servers, etc.) are part of a same HSDN label space, a server can
stack labels to pass through the hierarchy to reach destination within a
remote DC location without needing to pass through a traditional IP
Gateway.”), 52 (same), 76 (“Hence, the top label in the label stack implicitly
identifies the location (the micro data center 44, the aggregation CO 14b, the
local CO 14a, the hub CO 16, or the macro data center 42) as well as the
topmost layer in that location.”). The Examiner finds Blair’s disclosed
communication between data centers using MPLS, in combination with
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Dharwadkar’s disclosed MPLS label stacking, teaches the same technique
and technology as the described and claimed invention. Ans. 15–16. The
Examiner finds that the “most outer label in the MPLS header” label stack in
both the invention and the proposed combination is the globally significant
label that is unique across the architecture, whereas the remaining inner
labels in both the invention and the proposed combination are locally
significant because they can be reused across the architecture—i.e., “utilized
locally within the individual data center locations.” Ans. 16–17.
We agree with the Examiner. Blair discloses using MPLS at the
Layer 2 virtual switches. See Blair ¶¶ 73, 91. Furthermore, based on the
evidence presented, Appellant fails to persuasively demonstrate that using a
globally significant fourth label, as found by the Examiner, would not have
been obvious to a person of ordinary skill in the art or present any evidence
that such a combination was “uniquely challenging or difficult for one of
ordinary skill in the art.” Leapfrog Enters., Inc. v. Fisher-Price, Inc., 485
F.3d 1157, 1162 (Fed. Cir. 2007) (citation omitted). In other words, we
agree with the Examiner, see Ans. 11–12, that a person of ordinary skill in
the art would have understood that Dharwadkar’s disclosure of popping a
label off the MPLS label stack, when combined with Blair’s cited teachings,
teaches or suggests a hierarchy of labels such that the outermost label is
globally significant (in order to distinguish between the different data center
locations), whereas the inner labels are locally significant and could be
reused within data centers.
Finally, we are unpersuaded by Appellant’s argument that the
Examiner’s rationale is insufficient. First, Appellant’s argument is a mere
conclusion without any explanation regarding the alleged deficiency in the
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rationale. See Appeal Br. 13–14. Moreover, the rejection is based on a
combination of Blair’s teaching of connecting data centers over EPLANs
that may use MPLS in virtual switches, Dharwadkar’s teaching of using
MPLS label stacking, and Kapadia merely to teach that the recited data
center architecture in which MPLS may be used. Final Act. 8–13; see Blair
¶ 74; Dharwadkar ¶ 4; Kapadia ¶¶ 20, 21, Fig. 2. The Examiner’s rationale
of incorporating Kapadia’s particular data center architecture to properly
address packets is a reason based on a rational underpinning supported by
Blair’s disclosure of connecting data centers using MPLS. In other words,
Blair is used merely to fill in details regarding the structure of Blair’s data
centers.
On this record, we are persuaded that a person of ordinary skill in the
art would have extended the existing MPLS hierarchical structure to another
layer in order to incorporate inter-data center communication. Accordingly,
we sustain the rejection of claims 1, 3–12, and 14–20 under 35 U.S.C. § 103.
DECISION SUMMARY
Claim(s)
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
20 112(b) Indefiniteness 20
1, 3–12, 14–20 103 Blair, Dharwadkar,
Kapadia
1, 3–12,
14–20

Overall
Outcome
1, 3–12,
14–20

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