Arista Networks, Inc.v.Cisco Systems, Inc.

Patent Trial and Appeal Board

Oct 19, 2015

09108071 (P.T.A.B. Oct. 19, 2015)

Trials@uspto.gov Paper 9
571-272-7822 Entered: October 19, 2015

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

ARISTA NETWORKS, INC.,
Petitioner,

v.

CISCO SYSTEMS, INC.,
Patent Owner.
____________

Case IPR2015-00973
Patent 6,377,577 B1
____________

Before BRYAN F. MOORE, MATTHEW R. CLEMENTS, and
PETER P. CHEN, Administrative Patent Judges.

MOORE, Administrative Patent Judge.

DECISION
Denying Institution of Inter Partes Review
37 C.F.R. § 42.108

I. INTRODUCTION
Petitioner, Arista Networks, Inc., filed a Petition for inter partes
review of claims 1, 2, 5, 7–10, 12–16, 18–22, 25, and 28–31 of U.S. Patent
No. 6,377,577 B1 (Ex. 1001, “the ’577 patent”). Paper 6 (“Pet.”). Patent
Owner, Cisco Systems, Inc., filed a Preliminary Response. Paper 8
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(“Prelim. Resp.”). Institution of an inter partes review is authorized by
statute when “the information presented in the petition . . . and any
response . . . shows that there is a reasonable likelihood that the petitioner
would prevail with respect to at least 1 of the claims challenged in the
petition.” 35 U.S.C. § 314(a); see 37 C.F.R. § 42.108. Upon consideration
of the Petition and the Preliminary Response, we conclude the information
presented does not show there is a reasonable likelihood that Petitioner
would prevail in establishing the unpatentability of any of claims 1, 2, 5, 7–
10, 12–16, 18–22, 25, and 28–31 of the ’577 patent.
A. Related Matters
The parties state that the ’577 patent is the subject of Cisco Systems,
Inc. v. Arista Networks, Inc., No. 4:14-cv-05343-JSW (N.D. Cal.), filed
December 5, 2014, and ITC Inv. No. 337-TA-945 (Network Devices,
Related Software and Components Thereof (II)), filed December 19, 2014).
Pet. 1; Paper 5 (Patent Owner’s Mandatory Notice). The ’577 patent is also
the subject of IPR2015-001049. Petitioner has also filed petitions requesting
inter partes review of other patents owned by Patent Owner: IPR2015-
00973 (U.S. Patent No. 6,377,577), IPR2015-00974 (U.S. 7,224,668),
IPR2015-00975 (U.S. Patent No. 8,051,211), IPR2015-00976 (U.S. Patent
No. 7,023,853), IPR2015-00978 (U.S. Patent No. 7,340,597), and IPR2015-
01050 (U.S. Patent No. 7,023,853).
B. The ’577 Patent
The ’577 patent is titled, “Access Control List Processing in
Hardware,” and relates generally to a method for performing access control
list processing in hardware using an associative memory. Ex. 1001,
Abstract. Data packets transmitted between network devices can be
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restricted using a technique known as “‘access control.’” Id. at 1:6–7. One
access control technique is to use access control lists or “ACLs” to
determine whether to permit or deny transmission of a packet to a particular
destination. Id. at 1:13–15 (“[T]he ACL describes which selected source
devices are permitted (and which denied) to send packets to which selected
destination devices.”).
The Specification provides an example of a known ACL format,
where each ACL includes “access control specifiers.” Id. at 1:17. These
specifiers contain information to match with incoming packets, and then
based on a match, specify a particular access result (e.g., whether
transmission of a packet is “specifically permitted or specifically denied”).
Id. at 1:16–27. Figure 1 of the ’577 patent is reproduced below.

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Figure 1 is a block diagram of a system for performing access control in
accordance with the ’577 patent. As shown in Figure 1, packet 130 arrives
at one of the system’s packet interfaces 101. Id. at 3:30–31. Routing
element 110 then selects one or more of the output interfaces to which the
packet should be forwarded. Id. at 3:32–36. Prior to forwarding, access
control element 120 determines whether to allow transmission of the packet.
Id. at 3:36–40. Figure 2 of the ’577 patent is reproduced below.

Figure 2 is a block diagram of an access control element which contains
access control patterns. When packet 130 arrives at access control element
120, a packet label 200 is created based on information derived from packet
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header 133 of packet 130. Id. at 4:1–4. The packet label goes to access
control memory 210, which attempts to match information from the packet
label to access control specifiers in memory 211. Id. at 4:34–47.
To perform this matching process, packet label 200 is compared to
label match mask 212 and label match pattern 213 of each access control
specifier 211. Id. If a match is found with a particular access control
pattern, priority encoder 200 selects the corresponding access control
specifier 211 with the highest priority and provides an indicator of that
access control specifier 211 to output port 202. Id. at 4:47–56. The indicator
specifies an access control result, which specifies if the packet should be
transmitted. Id. at 4:57–65.
C. Illustrative Claim
Claim 1 of the challenged claims of the ’577 patent is independent.
Claim 1 is illustrative of the claimed subject matter:
1. A method, including the steps of
maintaining a set of access control patterns in at least one
associative memory;
receiving a packet label responsive to a packet, said packet
label being sufficient to perform access control processing for said
packet;
matching matchable information, said matchable information
being responsive to said packet label, with said set of access control
patterns in parallel, and generating a set of matches in response
thereto, each said match having priority information associated
therewith;
selecting at least one of said matches in response to said priority
information, and generating an access result in response to said at
least one selected match; and
making a routing-decision in response to said access result.

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D. Asserted Grounds of Unpatentability
Petitioner contends that claims 1, 2, 5, 7–10, 12–16, 18–22, 25, and
28–31 of the ’577 patent are unpatentable based on the following specific
grounds (Pet. 9–41):
References Basis Challenged Claim(s)
Hendel
1
35 U.S.C. § 102
1, 2, 5, 7–10, 12–16,
18–22, 25, 28, 29, 31
Hendel and Muller
2
35 U.S.C. § 103 7, 22, 25, 28, 29, 31
Hendel, Muller, “and
knowledge of one of
ordinary skill”
35 U.S.C. § 103 30
Hendel and Elliot
3
35 U.S.C. § 103 25
II. DISCUSSION
A. Claim Construction
In an inter partes review, we construe claim terms in an unexpired
patent according to their broadest reasonable construction in light of the
specification of the patent in which they appear. 37 C.F.R. § 42.100(b); see
also In re Cuozzo Speed Techs., LLC, 793 F.3d 1268, 1278–79 (Fed. Cir.
2015). Consistent with the broadest reasonable construction, claim terms are
presumed to have their ordinary and customary meaning as understood by a
person of ordinary skill in the art in the context of the entire patent
disclosure. In re Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir.

1
U.S. Patent No. 6,081,522, filed June 30, 1997, issued June 27, 2000 (Ex.
1007, “Hendel”).
2
U.S. Patent No. 5,938,736, filed June 30, 1997, issued Aug. 17, 1999 (Ex.
1008, “Muller”).
3
U.S. Patent No. 5,867,495, filed Nov. 18, 1996, issued Feb. 2, 1999 (Ex.
1019, “Elliot”).
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2007). An inventor may provide a meaning for a term that is different from
its ordinary meaning by defining the term in the specification with
reasonable clarity, deliberateness, and precision. In re Paulsen, 30 F.3d
1475, 1480 (Fed. Cir. 1994).
Petitioner proposes constructions for the terms “access control,”
“associative memory,” “packet label,” “responsive,” and “megapacket.” Pet.
5–9. We determine that the terms “associative memory,” “packet label,”
“responsive,” and “megapacket” do not require express construction for
purposes of our Decision.
As to the term “access control,” Petitioner asserts that “[a] person of
skill in the art would have understood ‘access control’ to encompass
restrictions or modifications of the transmission of a packet.” Pet. 5.
Petitioner relies on the following passage from the Specification:
[T]he invention can be used to augment or override routing
decisions otherwise made by the router, using the access control
element 120. In addition to specifying the packet 130 is to be
dropped or forwarded to the higher-level processor, the access
control element 120 can alter the output interface, which was
selected by the routing element 110, to another selected output
interface. The invention can thus be used to implement QOS
(quality of service), and other administrative policies.

Ex. 1001, 6:9–18.
Patent Owner asserts “the plain and ordinary meaning of
‘access control’ is ‘restriction of packets from being transmitted from
selected source devices to selected destination devices.’” Prelim.
Resp. 10. Patent Owner relies on the following passage from the
Specification (id.):
In a computer network for transmitting information, messages
can be restricted from being transmitted from selected source
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devices to selected destination devices. In known computer
networks, this form of restriction is known as “access control”
and is performed by routers, which route messages (in the form
of individual packets of information) from source devices to
destination devices.

Ex. 1001, 1:4–10. Patent Owner also cites certain dictionary
definitions. Id. at 10–11. Patent Owner states that “modifying”
transmission is “nowhere in the record.” Id. at 10. Nonetheless,
Patent Owner does not explain why the embodiment cited by the
Petitioner above is not relevant to construing the claims.
Because the embodiment cited by Petitioner suggests that
access control may be used to change the destination address of a
packet, we apply a broader definition than proposed by Patent Owner.
We find the broadest reasonable construction of “access control” to
include restrictions or modifications on the intended destination
address to which a packet is to be transmitted.
Patent Owner also asserts that the terms “access result” and “access
control specifiers” should be limited to permit or deny decisions about
packets based on essentially the same argument as above. Prelim Resp. 11–
12, 14–15. Petitioner does not provide a proposed construction for those
terms. We decline to limit those terms as Patent Owner requests for the
same reasons stated above.
B. Asserted Anticipation by Hendel
Petitioner contends that claims 1, 2, 5, 7–10, 12–16, 18–22, 25, 28,
29, and 31 are unpatentable under 35 U.S.C. § 102 as anticipated by Hendel.
Pet. 13–33. Petitioner relies on the testimony of Dr. H. Johnathan Chao.
Ex. 1003.
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1. Hendel (Ex. 1007)
Hendel describes a system and method for forwarding packets using
multi-layer information in a multilayer network element that includes a
switching element comprising forwarding logic. Ex. 1007, 1:5–8, Figs. 1–3.
Hendel describes its approach using the OSI layer model for network
communications. Id. at 2:5–39. In particular, Hendel describes forwarding
logic 42 performing packet header analysis in both Layer 2 (“L2”) (i.e., “L2
Logic 62” (concerning link layer packet information)) and Layer 3 (“L3)”)
(i.e., “L3 Logic 64” (concerning network layer packet information)). Id. at
10:12–33, Fig. 4. Each of these compares L2 and L3 information for the
packet, respectively, to information stored in forwarding memory 40, which
is a content addressable memory (“CAM”). Id. at 8:55–61. Hendel
performs additional packet analysis in class logic 60. Id. at 11:49–60.
Merge logic 66 receives information relating to both layers, as well as
information from class logic 60, and determines what to do with the packet.
Id. at 10:47–52; see also Ex. 1003 ¶¶ 109–10. Hendel discusses using its
techniques for packet filtering (Ex. 1007, 9:21–25, ; 13:4–6), as well as for
network firewall applications. Id. at 14:8–12. It discusses that merge logic
66 may, in some circumstances, instruct that packets be discarded where
their proposed destination is inappropriate. Id. at 10:51–52. Hendel also
discusses techniques for finding the best match for a particular search
criteria among the various entries stored in the CAM. Id. at 12:51–55.
2. Analysis
Petitioner contends that Hendel discloses all the limitations of claims
1, 2, 5, 7–10, 12–16, 18–22, 25, 28, 29, and 31. Pet. 13–33. As to claim 1,
Petitioner asserts Hendel discloses maintaining access control patterns in an
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associative memory including receiving a packet label, matching
information from the packet label with the access control patterns to
generate a match with an associated priority, then generating a result based
on a selected match and making a routing decision in response to that result.
Pet. 13–20, citing Ex. 1003 ¶¶ 88–100.
Claim 1 recites generating an access result in response to said at least
one selected match. Ex. 1001, 14:21–38. Petitioner cites the following
language from Hendel: “[D]ata stored in associated memory 42 and pointed
to by the matching entry in the forwarding memory 40 serves to define the
actions that the switching element must do to forward the packet to the
appropriate destination(s).” Pet. 19 (citing Ex. 1007, 8:61–65) (emphasis
added). Petitioner also asserts, in relation to “access result,” “Hendel
[discloses] that merge logic 66 (in figure 4) will combine the layer 2 result
(forwarding result) and layer 3/layer 4 result (‘access result’) of the searches
on the forwarding memory and associated memory to determine a
forwarding decision for a given packet.” Id. at 20 (citing Ex. 1007, 10:47–
50). Petitioner continues, “[t]his decision may involve forwarding a packet,
or dropping a packet.” Id. (citing Ex. 1007, 9:21–25, 13:4–8; Ex. 1003 ¶
100 (further describing Hendel’s operation and its routing decisions))
(citations omitted). Finally, Petitioner states “[t]he merge logic then
instructs the input port what to do to properly handle the packet.” Id. (citing
Ex. 1007, 10:47–50).
Patent Owner argues “Hendel’s disclosures relating to ordinary packet
forwarding [fails to] meet the claimed ‘generating an access result in
response to said at least one selected match.’” Prelim. Resp. 20. Patent
Owner also argues that “Hendel’s minimal references to ‘filtering’ or
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‘discarding’ packets does not concern access control,” that Hendel’s
“packets are only filtered or discarded as part of the packet forwarding
process when there is a problem with the packet,” and thus, “Hendel refers
to such filtering or discarding occurring when packets are ‘ill-formed’ or
have ‘no appropriate destination[s]’ or ‘unsupported’ headers.” Prelim
Resp. 21–22 (citing Ex. 1007, 8:39–40, 10:51–52, 13:9–11). We agree.
Although we did not adopt Patent Owner’s proposed construction of the
claim term “access result,” Patent Owner nevertheless makes a salient
argument. We find Petitioner has not shown that the filtering decision is
done “in response to [] at least one selected match” as required by claim 1.
The Specification supports that a successful match leading to an
access result is contemplated by the claims. Ex. 1001, 7:1–12, 27–39
(determining an input [or output] permission by, among other things,
“determining all of the successful matches”); see also Prelim. Resp. 21 (“the
‘matching entry,’ at most, provides a destination for Hendel’s system to
forward the packet . . . [but,] where a destination is found, the packet is
forwarded; there is no disclosure to generate any access result to possibly
restrict access to the destination.”). Neither Petitioner, nor Petitioner’s
Declarant, has tied an actual match in Hendel to a decision whether to
forward the packet or make some modification to the intended transmission
of the packet.
For the reasons stated above, we determine Petitioner has not shown
sufficiently that Hendel discloses all of the limitations of independent claim
1. Accordingly, the information presented does not show a reasonable
likelihood that Petitioner would prevail in showing that independent claim 1,
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or claims 2, 5, 7–10, 12–16, 18–22, 25, 28, 29, and 31 that depend
therefrom, are anticipated by Hendel.
C. Asserted Obviousness Grounds
Petitioner argues that: dependent claims 7, 22, 25, 28, 29, and 31 are
unpatentable under 35 U.S.C. § 103(a) over Hendel and Muller; dependent
claim 30 is unpatentable under 35 U.S.C. § 103(a) over Hendel, Muller, and
the knowledge of one of ordinary skill; and dependent claim 25 is
unpatentable under 35 U.S.C. § 103(a) over Hendel and Elliot. As discussed
above, Petitioner has not shown sufficiently that Hendel discloses
“generating an access result in response to said at least one selected match,”
as is required by independent claim 1. Additionally, for these grounds,
Petitioner does not rely on Muller, Elliot, or the knowledge of one of
ordinary skill to teach or suggest this limitation or otherwise cure the
deficiency in Hendel. Thus, upon review of Petitioner’s analysis and
supporting evidence and Patent Owner’s analysis and supporting evidence,
we determine that Petitioner has not demonstrated that there is a reasonable
likelihood that it would prevail with respect to the ground that claims 7, 22,
25, and 28–31 are unpatentable.
III. CONCLUSION
The information presented does not show that there is a reasonable
likelihood that Petitioner would prevail at trial with respect to at least one
claim of the ’577 patent, based on any grounds presented in the Petition. On
this record, we deny the petition for inter partes review of claims 1, 2, 5, 7–
10, 12–16, 18–22, 25, and 28–31.
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ORDER
Accordingly, it is
ORDERED that that the petition is DENIED as to all challenged
claims, and no trial is instituted.

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PETITIONER:
Walter Renner
Kevin E. Greene
FISH & RICHARDSON P.C.
IPR40963-0004IP1@fr.com
axf@fr.com

PATENT OWNER:
Lori A. Gordon
Robert G. Sterne
Jon E. Wright
Byron L. Pickard
STERNE, KESSLER, GOLDSTEIN & FOX P.L.L.C.
lgordon-PTAB@skgf.com
rsterne-PTAB@skgf.com
jwright-PTAB@skgf.com
bpickard-PTAB@skgf.com