Arista Networks, Inc.

Patent Trials and Appeals Board

Oct 4, 2021

2020003967 (P.T.A.B. Oct. 4, 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.
15/155,940 05/16/2016 Kenneth James Duda 170383-001703US 2776
148194 7590 10/04/2021
Arista/CHWWA
1200 Smith St., 14th Floor
Houston, TX 77002
EXAMINER
BAIG, ADNAN
ART UNIT PAPER NUMBER
2461
NOTIFICATION DATE DELIVERY MODE
10/04/2021 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):
Dossa.IP@chamberlainlaw.com
Jeff.Guinn@chamberlainlaw.com
Patents@chamberlainlaw.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte KENNETH JAMES DUDA and
ADAM JAMES SWEENEY

Appeal 2020-003967
Application 15/155,940
Technology Center 2400

Before JEAN R. HOMERE, ST. JOHN COURTENAY III, and
LARRY J. HUME, Administrative Patent Judges.
HOMERE, Administrative Patent Judge.

DECISION ON APPEAL
I. STATEMENT OF THE CASE1
Pursuant to 35 U.S.C. § 134(a), Appellant2 appeals from the
Examiner’s decision to reject claims 21–26 and 28–40 which constitute all
of the claims pending. Claims App. Claims 1–20 and 27 are cancelled. Id.
We have jurisdiction under 35 U.S.C. § 6(b).

1 We refer to the Specification, filed May 16, 2016 (“Spec.”); the Final
Office Action, mailed Apr. 25, 2019 (“Final Act.”); the Appeal Brief, filed
Nov. 15, 2019 (“Appeal Br.”); the Examiner’s Answer, mailed Mar. 5, 2020
(“Ans.”).
2 “Appellant” refers to “[A]pplicant” as defined in 37 C.F.R. § 1.42(a).
Appellant identifies the real party in interest as Arista Networks, Inc.
Appeal Br. 4.
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We affirm.
II. CLAIMED SUBJECT MATTER
According to Appellant, the claimed subject matter relates to using
overlay routing mechanisms (including direct/indirect/naked routing) in an
Internet Protocol (IP) fabric to enable communication by routing packets
between hosts or virtual machines in different layer 2 domains to
communication. Abst.
Figure 3, reproduced below, is useful for understanding the claimed
subject matter:

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Figure 3 depicts servers S1 (including virtual machines A1 and B1)
and S2 (including virtual machines A2 and B2) configured to generate, send,
receive and process associated MAC frames and virtual tunnel end points
(VTEPs). Spec. ¶¶ 41, 42. Each VTEP includes functionality to generate and
process VXLAN frames in accordance with VXLAN protocol for overlaying
virtualized layer 2 networks over layer 3 networks. Id. ¶ 42.
Claims 21, 28, and 36 are independent. Claim 21 is representative of
the claimed subject matter (disputed limitations emphasized):
21. A method for routing, comprising:
receiving, by a network device, a first encapsulated packet
addressed to the network device,
wherein the first encapsulated packet comprises an
inner packet comprising a VARP address,
wherein:
the VARP address is a media access control (MAC)
address, the VARP address is associated with a
Virtual Tunnel End Point (VTEP) executing on the
network device, and with a first layer 2 domain, and
the existence of the VARP address in the received
inner packet alerts the network device that the inner
packet requires routing to a second layer 2 domain;
decapsulating, by the network device, the first
encapsulated packet to obtain the VARP address of the inner
packet;
processing, by the network device and based at least in part
on the VARP address, the inner packet to obtain a rewritten inner
packet comprising a destination address;
generating, by the network device, a second encapsulated
packet comprising the rewritten inner packet; and
routing, by the network device, the second encapsulated
packet towards a destination identified by the destination
address, wherein the destination is in the second layer 2 domain.
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III. REFERENCES
The Examiner relies upon the following references as evidence.3
Name Reference Date
Zhang US 2014/0146817 A1 May 29, 2014
Nakil US 2015/0244617 A1 Aug. 27, 2015

IV. REJECTION
The Examiner rejects claims 21–26 and 28–40 under 35 U.S.C. § 103
as unpatentable over the combined teachings of Nakil and Zhang. Final Act.
10.
V. ANALYSIS
We consider Appellant’s arguments seriatim, as they are presented in
the Appeal Brief, pages 6–12.4 We are unpersuaded by Appellant’s
contentions on the sole obviousness rejection. Except as otherwise indicated
herein below, we adopt as our own the findings and reasons specific to the
obviousness rejection set forth in the Final Action, and the Examiner’s
Answer in response to Appellant’s Appeal Brief. Final Act. 10–15; Ans. 3–
11. However, we highlight and address specific arguments and findings for
emphasis as follows.

3 All reference citations are to the first named inventor only.
4 We have considered in this Decision only those arguments Appellant
actually raised in the Brief. Arguments not made are forfeited. See 37 C.F.R.
§ 41.37(c)(1)(iv) (2017).
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Appellant selects independent claim 21 as representative of all the
claims on appeal. Appeal Br. 6. Appellant argues the references Nakil and
Zhang do not teach or suggest the disputed limitations
the VARP address is a media access control (MAC) address,
the VARP address is associated with a Virtual Tunnel End Point
(VTEP) executing on the network device, and with a first layer 2
domain, and
the existence of the VARP address in the received inner packet
alerts the network device that the inner packet requires routing
to a second layer 2 domain.
Appeal Br. 8.
Appellant disagrees with the Examiner’s finding that Zhang’s inner
MAC destination address teaches or suggests the VARP address is a MAC
address associated with a VTEP executing on the network device. Appeal
Br. 8–9. Appellant argues in particular that Zhang does not teach an inner
MAC destination address associated with a VTEP. Appeal Br. 9. Appellant’s
arguments are not persuasive.
The Examiner finds, and we agree, Zhang’s VXLAN encapsulation
packet 260 and 270 teaches or at least suggests an “inner packet” and
Zhang’s Inner MAC DA 271 teaches a “VARP address.” Ans. 5.
The Examiner correctly notes that Appellant’s Specification describes
the VARP address as a destination MAC address. Id. citing to Specification
at ¶¶ 51, 52.5 The Examiner further correctly finds Zhang’s VXLAN VTEP
152 of the server 150 (Fig. 2, VTEP 252) contains functionality needed to
tunnel packets of the VMs or other endpoints over L2/L3 networks (Fig. 2,

5 See Spec. ¶51: “In one embodiment of the invention, the VARP MAC
address corresponds to the MAC address that hosts (or virtual machines) use
to send MAC frames that require routing.”
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L2/L3 Network 225, ¶ 16) at least suggests “a . . . VTEP executing on the
network device, and with a first layer 2 domain.” Ans. 7. The Examiner
makes a reasonable finding that under a broad but reasonable interpretation
the VARP address of the packet is associated with the VTEP because the
VTEP constrains functionality needed to tunnel packets of VMS or other
endpoints over L2/L3 networks and therefore a VARP address, such as the
destination MAC address 271, will be used by the VTEP for processing and
tunneling the packet to its destination. Ans. 7. It is in light of this finding
that the Examiner concludes the disputed limitation “the VARP address is
associated with a Virtual Tunnel End Point (VTEP) executing on the
network device, and with a first layer 2 domain” is taught or suggested by
Zhang’s cited teachings. Id.
Appellant did not file a Reply Brief to respond to the Examiner’s
clarifications or contest the Examiner’s additional findings and dispute the
Examiner’s reasoning in the Answer. Therefore, Appellant’s argument does
not show error in the Examiner’s factual findings of obviousness nor
persuasively rebut the rejection. Because Appellant did not file a Reply
Brief to rebut the Examiner’s additional findings, legal conclusions, and
clarifications, on this record, we are not persuaded the Examiner erred.
Appellant moreover argues Zhang does not teach the “inner MAC
destination address” as alerting “a network device that a packet requires
routing to a different layer 2 domain.” Appeal Br. 11.
Appellant argues “Zhang certainly does not describe the ‘inner MAC
destination address’ as alerting any entity of anything, much less that it alerts
a network device that a packet requires routing to a different layer 2
domain.” Id. Appellant argues the sections of
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Zhang expressly included in the Action describe that after a
decision has been made that a packet requires routing to an external
domain, . . . but before the packet leaves the server, the ‘inner MAC
destination address’ is replaced with the server VTEP MAC address
‘merely to hide the VM MAC address from devices in the external
domain.’
Id.
We are not persuaded by Appellant’s arguments because the
Examiner makes a reasonable finding in the Answer that the VARP address
will alert any network device in the network system which receives the
packet to route it according to its destination MAC address received.
Ans. 10, citing Zhang ¶¶ 16, 19. The Examiner explains this is “because
routing or tunneling of packets is performed at each network device or
switch according to the information received in the received packet which
includes the VARP address or destination MAC address used for routing the
packet.” Ans. 10. The Examiner further finds in the Answer that under a
broad but reasonable interpretation of claim 21:
[T]he action of receiving the packet at the network device
including the destination information such as the destination MAC
address will be used by the network device for routing purposes and
thus the step of receiving such packet header information may alert
the network device to route the packet to the second layer 2 domain or
the destination.
Ans. 10 (emphasis added).
Appellant did not file a Reply Brief to respond to the Examiner’s
additional findings and dispute the Examiner’s reasoning in the Answer.
Because Appellant did not file a Reply Brief to rebut the Examiner’s
additional findings and clarifications, on this record, we are not persuaded
the Examiner erred.
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Therefore, on this record, and based upon a preponderance of the
evidence, we are not persuaded of Examiner error and so we sustain the
Examiner’s obviousness rejection of representative independent claim 21
and grouped claims 22–26 and 28–40. See 37 C.F.R. § 41.37(c)(1)(iv). See
Appeal Br. 6.
VI. CONCLUSION
We affirm the Examiner’s obviousness rejection under 35 U.S.C.
§ 103(a) of claims 21–26 and 28–40.
In summary:
Claim(s)
Rejected
35
U.S.C. § Reference(s)/Basis Affirmed Reversed
21–26,
28–40
103 Nakil, Zhang 21–26,28–40

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). See 37
C.F.R. § 41.50(f).
AFFIRMED