Ex Parte 6502135 et al

Patent Trial and Appeal Board

Feb 6, 2018

95001679 (P.T.A.B. Feb. 6, 2018)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

CISCO SYSTEMS, INC.,
Requester,

v.

VIRNETX INC.,
Patent Owner.
____________

Appeal 2017-011862
Reexamination Control 95/001,679
Patent 6,502,135 B1
Technology Center 3900
____________

Before STEPHEN C. SIU, DENISE M. POTHIER, and
JEREMY J. CURCURI, Administrative Patent Judges.

SIU, Administrative Patent Judge

DECISION ON APPEAL
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VirnetX, Inc. (“Patent Owner”) appeals under 35 U.S.C. §§ 134 and
315 the Examiner’s rejections of claims 1–9 and 13–18 over various
references. App. Br. 3.1 Claims 10–12 are not subject to this reexamination
proceeding. See id. at vi. We have jurisdiction under 35 U.S.C. §§ 134 and
315.

STATEMENT OF THE CASE
This proceeding arose from a July 8, 2011 request by Cisco Systems,
Inc. (“Requester”) for an inter partes reexamination of claims of U.S. Patent
6,502,135 B1, titled “Agile Network Protocol for Secure Communications
with Assured System Availability” and issued to Edmund Colby Munger,
Douglas Charles Schmidt, Robert Dunham Short, III, Victor Larson, and
Michael Williamson, on December 31, 2002 (“the ’135 patent”).
The ’135 patent describes a method and system for communicating
over the internet. Spec. 2:66.

Claim 1 reads as follows:

1. A method of transparently creating a virtual private
network (VPN) between a client computer and a target computer,
comprising the steps of:
(1) generating from the client computer a Domain Name
Service (DNS) request that requests an IP address corresponding to a
domain name associated with the target computer;
(2) determining whether the DNS request transmitted in step (1)
is requesting access to a secure web site; and

1 Patent Owner’s Appeal Brief, filed December 15, 2015 (App. Br.).
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(3) in response to determining that the DNS request in step (2)
is requesting access to a secure target web site, automatically
initiating the VPN between the client computer and the target
computer.

The cited references are as follows:

Wesinger US 5,898,830 April 27, 1999
Aziz US 6,119,234 Sept. 12, 2000
Karr US 7,764,231 B1 July 27, 2010

D.E. Denning & G.M. Sacco, “Timestamps in Key Distribution
Protocols,” Communications of the ACM, Vol. 24, No. 8, August
1981 (“Denning”).

Steven M. Bellovin & Michael Merritt, “Encrypted Key Exchange:
Password-Based Protocols Secure Against Dictionary Attacks,” 1992
IEEE Symposium on Security and Privacy, 1992 (“Bellovin”).

Takahiro Kiuchi & Shigekoto Kaihara, “C-HTTP – The Development
of a Secure, Closed HTTP-based Network on the Internet,”
Proceedings of SNDSS, 1996 (“Kiuchi”).

C.I. Dalton & J.F. Griffin, “Applying Military Grade Security to the
Internet,” Proceedings of the 89th Joint European Networking
Conference (JENC 8), May 1997 (“Dalton”).

Eduardo Solana & Jurgen Harms, “Flexible Internet Secure
Transactions Based on Collaborative Domains,” Security Protocols
Workshop, 1997 (“Solana”).

David M. Martin, “A Framework for Local Anonymity in the
Internet,” Boston University, February 21, 1998 (“Martin”).

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Patent Owner appeals the Examiner’s rejection of claims as follows:
1. Claims 1–4, 7, 13, 14, and 17 under 35 U.S.C. § 102(b) over
Kiuchi;
2. Claims 1–5, 7-9, 13, and 18 under 35 U.S.C. § 102(e) over
Wesinger;
3. Claims 1–5, 7, 8, and 18 under 35 U.S.C. § 103 over Solana and
Kiuchi;
4. Claims 1–5, 7, and 18 under 35 U.S.C. § 102(e) over Aziz;
5. Claims 5, 8, and 18 under 35 U.S.C. § 103 over Kiuchi and any
one of either Dalton or the combination of Dalton and Solana;
6. Claim 6 under 35 U S.C. § 103 over (a) the combination of Kiuchi
and Martin with or without Solana, (b) the combination of
Wesinger and Martin, or (c) the combination of Aziz and Martin;
7. Claim 9 under 35 U.S.C. § 103 over the combination of Bellovin
and any one of (a) Kiuchi, (b) Aziz or (c) the combination of
Solana, Kiuchi, and Dalton;
8. Claim 13 under 35 U.S.C. § 103 over Aziz and Kiuchi;
9. Claims 13–15 under 35 U.S.C. § 102(b) over Solana;
10. Claim 16 under 35 U.S.C. § l03 over Solana and Karr;
11. Claim 17 under 35 U.S.C. § 103 over Solana and Denning;
ISSUE

Did the Examiner err in rejecting claims 1–9 and 13–18?

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ANALYSIS

Prior art references

Martin
Patent Owner argues that although the Martin reference indicates a
publication date of “‘21st February 1998’ on its first page, nowhere in Martin
is there any indication as to what that date means.” App. Br. 4. However,
Patent Owner does not argue persuasively that one of skill in the art, when
confronted with a date of “21st February 1998” on a first page of a
publication, would need further explanation within the reference as to “what
that date means.” Rather, one of skill in the art, being of ordinary creativity
and not being an automaton would have understood that “21st February
1998” is a date that specifies the 21st day in the month of February and in the
year of 1998. Further, one of skill in the art, being of ordinary creativity and
not being an automaton would have understood the context of a date printed
on the face of a reference article as being the date on which the date was
published. Therefore, we are not persuaded by Patent Owner’s implication
that because the Martin reference allegedly lacks a detailed explanation as to
“what that date means,” that Requester provided an insufficient showing that
the Martin reference was published (and publicly available) on the indicated
date.
In any event, Requester provides further evidence supporting the
contention that the Martin reference was publicly available by the indicated
date of “21st February 1998.” In particular, Requester provides a document
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“available through the Wayback Machine” that “establishes that the Martin
paper was cataloged in the Boston University Technical Reports Archive
and available to the public via the Internet even earlier than the February 21,
1998 date” and a “German thesis, unambiguously dated 1999 . . . cites the
Martin paper at page 77.” 3PR Resp. Br. 3.2 Patent Owner does not appear
to dispute the contents of Requester’s submitted evidence with respect to this
issue.
Patent Owner argues that Requester’s evidence with respect to this
issue “should be rejected and . . . not be considered” and “it is not a
‘rebuttal’ because Patent Owner contended only that Cisco had failed to
satisfy its burden in its request.” App. Br. 5. In other words, Patent Owner
now argues that Patent Owner never argued that the Martin reference was
not publicly available as of the critical date. Assuming Patent Owner’s
contention to be correct that Patent Owner never raised the issue of public
availability of the Martin reference, then we need not further consider the
issue of public availability of the Martin reference, the public availability of
the Martin reference not now or ever having been at issue in this proceeding.
Lastly, the Manual of Patent Examining Procedure (MPEP) § 2646(II)
states:
[N]either the patent owner nor the third party requester has the
right to . . . request reconsideration of, a finding that the prior
art patents or printed publications raise a SNQ/RLP . . . Where
the examiner determines that a reference is a printed publication
(i.e., that the criteria for publication has been satisfied), . . .

2 Third Party Requester Cisco Systems, Inc.’s Corrected Respondent Brief,
filed February 9, 2016 (“3PR Resp. Br.”).
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[t]hese matters cannot be questioned with respect to vacating
the order granting reexamination.”

MPEP § 2646(II), Rev. 07.2015 (Oct. 2015). Thus, to the extent the above
Patent Owner’s arguments asserting Requester’s purported failure “to satisfy
its burden in its request” (App. Br. 5) contends that Martin fails to raise a
SNQ/RLP and this reexamination proceeding should not vacated on these
grounds, Patent Owner is not permitted to question these matters. See id.;
see also 35 U.S.C. § 312 (pre-AIA).

Dalton
Patent Owner argues that Requester “provided no evidence that
Dalton was publicly accessible as of the alleged date [of October 30, 1998].”
App. Br. 5. To the extent that Patent Owner argues that the Dalton reference
was not publicly accessible “as of the alleged date [of October 30, 1998],”
Requester provides further evidence supporting the contention that the
Dalton reference was publicly available prior to the priority date of the ’135
patent. In particular, Requester argues that “[t]he Dalton paper was
originally disseminated with the Proceedings of the 8th Joint European
Networking Conference (JENC 8) held May 12-15, 1997” and provides “a
copy of the Dalton reference as it was published by Elsevier, indicating on
its face that the Dalton paper was received on July 1, 1997 and republished
in Volume 29 of the journal in 1997 at pages 1799-1808.” 3PR Resp. Br.
3–4. Requester also “provides an E2S Consortium publication,
unambiguously dated 1997, that cites the Dalton paper at page 67.” 3PR
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Resp. Br. 3–4. Patent Owner does not appear to dispute the contents of
Requester’s submitted evidence with respect to this issue.
Patent Owner argues that Petitioner’s “evidence should have been
provided with Cisco’s Request” but does not explain sufficiently why
Requester’s evidence pertaining to the public availability of the Dalton
reference should have been submitted prior to the point in time of the
proceeding at which Patent Owner allegedly raised the issue. App. Br. 5.
To the extent that Patent Owner now argues that Patent Owner never raised
the issue of public availability of the Dalton reference in the course of this
proceeding, we need not further address this “issue,” the “issue” never
having been raised in the first place.

Solana
Patent Owner argues that Requester “provided no evidence that
Solana was publicly accessible more than one year prior to the alleged
earliest effective date of Feb. 25, 2000.” App. Br. 6. To the extent that
Patent Owner argues that the Solana reference was not publicly accessible as
of “the alleged earliest effective date of Feb. 25, 2000,” Requester provides
further evidence supporting the contention that the Solana reference was
publicly available prior to the priority date of the ’135 patent. In particular,
Requester argues that “[t]he Solana reference was made available to the
public in 1997 as part of the proceedings of the 5th International Workshop
on Security Protocols” and
provides a copy of the cover of the bound volume for the
5th Internet Workshop on Security Protocols, indicating that the
proceedings occurred in April 1997; a title page from the bound
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volume indicating that the 5th International Workshop was held
in Paris, France from April 7-9, 1997; a copyright page that
includes ISBN number 3-540-64040-1 which corresponds to a
February, 1998 publication date for the bound volume; . . . the
table of contents showing the Solana paper begins on page 37 . .
. [; and] a copy of the ISBN number search results which
indicate that ISBN number 3-540-64040-1 corresponds to a
publication date of February 1998.

3PR Resp. Br. 4. Patent Owner does not appear to dispute the contents of
Requester’s submitted evidence with respect to this issue.
Patent Owner argues that Petitioner’s “evidence should have been provided
with Cisco’s Request” but does not explain sufficiently why Requester’s
evidence pertaining to the public availability of the Dalton reference should
have been submitted prior to the point in time of the proceeding at which
Patent Owner allegedly raised the issue. App. Br. 6. To the extent that
Patent Owner now argues that Patent Owner never raised the issue of public
availability of the Solana reference in the course of this proceeding, we need
not further address this “issue,” the “issue” never having been raised in the
first place.

Solana (claims 13–15); Solana and Dalton (claim 16); Solana and Denning
(claim 17)

Claim 13 recites a “central computer” receiving “a request to establish
a connection.” We agree that Solana discloses general methods to “provide
Internet transactions with adequate security features” including “the
provision of secure end-to-end transactions” in which an “initiator generates
a session key . . . a header containing the session key . . . the UNI of the
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responder . . . [and a] header.” Solana 37, 43, 45. Hence, Solana discloses a
method for establishing a secure connection (i.e., a “secure end-to-end
transaction”) in which an initiating device sends data that results in the
formation of the secure connection.
Patent Owner argues that Solana discloses a “packet shown arriving at
the D-DBS’ in Figure 2a” but that this “packet” “does not include a request
to establish a connection.” App. Br. 41. Patent Owner also argues that
Solana discloses a “destination address and a session key” and a “header”
but that “the mere inclusion of a destination address in the header . . . does
not transform the packet into a request for connection.” App. Br. 41. We
are not persuaded by Patent Owner’s argument at least because Patent
Owner does not explain persuasively how the initiating device sending data
that results in establishing a secure connection differs from a “request” to do
so. In both cases, an initiating device provides a transmission that results in
the establishment of a secure connection.
Claim 13 recites a method involving a computer that maintains
“authentication tables each corresponding to one of the client computers”
and authenticating “with reference to one of the . . . authentication tables.”
Patent Owner argues that Solana discloses a Local Authentication Database
(i.e., “LAD”) but fails to disclose “authentication tables,” as recited in claim
13. App. Br. 42. Hence, Patent Owner argues that the Local Authentication
Database of Solana differs materially from the claimed authentication table.
Solana discloses a Local Authentication Database (LAD) “that will
contain for each principal (UNI) the local authentication credentials” in
which reference to an LAD “verif[ies] the identity of [the] principals inside
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its domain.” Solana 43–44. Hence, Solana discloses an LAD that contains
authentication data for each “principal” (e.g., an index/table). Similarly,
claim 13 recites an authentication table corresponding to a client computer
(or corresponding to a principal) and authenticating a computer (or
principal) with reference to one of the authentication tables (or with
reference to a corresponding LAD in Solana). Patent Owner fails to explain
sufficient distinguishing characteristics between the claimed “authentication
table” and the “LAD” of Solana.
Patent Owner argues that Solana fails to disclose “that the alleged
request to establish a connection . . . is authenticated using the LAD entries.”
App. Br. 43. As Patent Owner points out, claim 13 recites “authenticating,
with reference to one of the . . . authentication tables, that the request
received in step (1) is from an authorized client.” App. Br. 43. As
previously discussed, Solana discloses this feature. For example, Solana
discloses that reference to an LAD “verif[ies] the identity of the principals in
its domain.” Solana 43–44. In other words, Solana discloses authenticating
(or “verifying”) that the request is from an authorized client with reference
to an authentication table (or with reference to an “LAD”), as recited in
claim 13.
Patent Owner also argues that Solana fails to disclose each element of
claim 13 because, according to Patent Owner, Requester has combined
elements from two different embodiments of Solana (namely one
embodiment illustrated in Figure 2a of Solana and a second embodiment
illustrated in Figure 3a of Solana), which Patent Owner argues is
impermissible in establishing anticipation of a claimed invention over a prior
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art reference. App. Br. 44–45. Requester argues that both Figure 2a of
Solana and Figure 3a of Solana describe “different tasks” for the same
“overall approach ‘to achieve confidentiality and authentication.’” 3PR
Resp. 18 (citing Solana 37). Solana discloses that it was known in the art to
“provide[] a proof of identity of the entity originating the transaction” and
illustrates “different kinds of authentication [that] are possible” in Figure 3a.
Solana 46–47. Solana also discloses that it was known in the art to “achieve
end-to-end confidentiality using domain collaborations” and describes
alternatives “to achieve end-to-end confidentiality using domain
collaborations.” Solana 45, Fig. 2a. We agree with Requester that Solana
discloses a method of establishing a secure connection between entities in
which it was known to those of skill in the art that such a system and method
would achieve both “authentication” and “confidentiality” using known
methods as disclosed by Solana in Figures 3a and 2a, respectively.
In response, Patent Owner reiterates that Requester “impermissibly
combine[s] the teachings of two distinct embodiment for an anticipation
rejection” because “Figures 2a and 3a represent distinct embodiments in
Solana with Figure 2a directed solely to confidential communications, and
Figure 3a directed solely to authenticated communications.” Reb. Br. 21.
However, Patent Owner does not explain persuasively how Solana’s
disclosure of the establishment of a confidential communication link
between entities in which users are authenticated constitute “two distinct
embodiments.” Rather, Solana disclose potentially multiple approaches to
achieving the establishment of a confidential communication link between
authenticated entities.
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Dependent claim 15 recites comparing an Internet Protocol (IP)
address in a header of each data packet to a table of valid IP addresses
maintained in a table in the second computer. Patent Owner does not
dispute that Solana discloses a “responder” (i.e., second computer) that
“verifies the identity (the UNI) of the initiator,” which “include[s] an IP
address” but contends that Solana fails to explicitly disclose that the
responder (or second computer) maintains a table of IP addresses, as recited
in claim 15. App. Br. 45–47. However, Patent Owner does not explain
persuasively that one of skill in the art would not have understood Solana’s
computer that verifies the identity of another network entity via
identification of an IP address would include the IP address being identified.
We agree with the Examiner and Requester that one of skill in the art, given
the knowledge that a “responder” uses a corresponding IP address to identify
a network entity, would have recognized Solana’s computer included the IP
address with which to identify the network entity in some type of data
structure (e.g., a table). Otherwise, the responder would have been unable to
identify the network entity with the corresponding IP address, the responder
not having the corresponding IP address with which to identify the network
entity. This would have been in direct contrast to the explicit teaching of
Solana that the responder, in fact, identifies the network entity via the
corresponding IP address.
Patent Owner does not provide further arguments in support of claim
14 with respect to this issue. The Examiner did not err in rejecting claims
13–15 as anticipated by Solana.
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Dependent claim 16 recites “a moving window of valid IP addresses.”
The Examiner finds that “Solana teaches . . . valid IP addresses” and that
Karr discloses a “moving window of information.” RAN 29 (quoting 3PR
April 9, 2014 Response, p. 34).3 Hence, the Examiner finds that one of skill
in the art would have known that such information may be used in a
“moving window.” See id. Given this teaching, it would have been obvious
that information, including known “valid IP address” as disclosed in Solana,
would have been provided in a known “moving window,” as taught by Karr.
Patent Owner argues that Karr fails to disclose “a moving window of
valid IP addresses,” as recited in claim 16. However, as discussed above,
the Examiner relies on the combination of Solana and Karr as disclosing or
suggesting a “moving window of valid IP addresses” and not on Karr alone.
Therefore, even assuming Patent Owner to be correct that Karr, in isolation,
fails to disclose or suggest a “moving window of valid IP addresses,” Patent
Owner does not assert or demonstrate sufficiently that the combination of
Solana and Karr also fails to disclose or suggest the disputed claim
limitation.
Patent Owner does not provide additional arguments in support of
dependent claim 17 with respect to Denning.
The Examiner did not err in rejecting claims 13–15 as anticipated by
Solana, claim 16 as unpatentable under 35 U.S.C. § 103(a) over Solana and
Karr, or claim 17 as unpatentable under 35 U.S.C. § 103(a) over Solana and
Denning.

3 Right of Appeal Notice, dated September 15, 2015 (“RAN”).
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Kiuchi (claims 1–4, 7, 13, 14, and 17); Kiuchi and Solana (claims 1–5, 7, 8,
and 18); Kiuchi and Dalton (claims 5 and 8); Kiuchi, Solana, and Dalton
(claims 5, 8, and 18); Kiuchi and Martin (claim 6); Kiuchi and Bellovin
(claim 9)

Patent Owner argues that Kiuchi discloses a “client-side proxy” and a
“server-side proxy” but fails to disclose a “client computer” or a “target
computer,” respectively, as recited in claim 1.
Claim 1 recites creating a network between a client computer and a
target computer and generating from the client computer a Domain Name
Service (DNS) request. Patent Owner argues that the claimed “client
computer” must be a “user’s computer” and that Kiuchi fails to disclose a
“user’s computer.” App. Br. 10. However, Patent Owner does not explain
sufficiently how Kiuchi fails to disclose a “client computer,” which claim 1
recites. As the Examiner points out, Kiuchi discloses a client-side proxy that
generates a Domain Name Service (DNS) request. Even assuming that
claim 1 recites a “user’s computer” (instead of a “client computer,” which
claim 1 actually recites) that generates a Domain Name Service (DNS)
request, as Patent Owner appears to allege, Patent Owner does not
demonstrate persuasively that the hypothetical “user’s computer” (renamed
from “client computer”) differs from the client-side proxy of Kiuchi, which
also generates a Domain Name Service (DNS) request. See e.g., Kiuchi 64–
65.
Patent Owner argues that the client-side proxy of Kiuchi differs from
the claimed “client computer” because “Kiuchi discloses a communication
system in which . . . a ‘user agent,’ at one institution is able to securely
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access its target.” App. Br. 11. In other words, Patent Owner argues that
Kiuchi discloses a “user agent” that corresponds to the claimed “client
computer” such that Kiuchi’s client-side proxy cannot also correspond to the
claimed “client computer.” We need not consider whether or not Kiuchi’s
“user agent” also discloses the claimed “client computer,” as Patent Owner
appears to contend, because Patent Owner does not demonstrate
persuasively that Kiuchi’s client-side proxy (equated to the claimed “client
computer” by the Examiner) does not generate a Domain Name Service
(DNS) request, as recited in claim 1. As noted above, Kiuchi discloses that
the client-side proxy performs this recited function.
Patent Owner argues that Kiuchi discloses “separate references to the
‘client’ and ‘client-side proxy’ . . . [and] demonstrates that the client-side
proxy is not the client itself” such that “Kiuchi . . . distinguishes between a
‘client,’ where an end-user sits, and a ‘client-side proxy,’ which has no end-
user.” App. Br. 11–12. In other words, Patent Owner argues that Kiuchi
discloses that the “client-side proxy” “has no end-user” and fails to disclose
that the “client-side proxy” is “where an end-user sits.” Claim 1 recites
“generating from the client computer a Domain Name Service (DNS)
request. Claim 1 does not also recite that the client computer must have an
“end-user” or that the client computer must be “where an end-user sits.”
Indeed, claim 1 does not recite an “end-user” at all. For at least this reason,
we are not persuaded by Patent Owner’s argument.
Patent Owner argues that the Federal Circuit has held that there was
“evidence” that a “web browser” of Kiuchi is “distinguishable from the
client-side proxy [of Kiuchi].” App. Br. 12. However, Patent Owner does
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not indicate the probative value of the “evidence” or whether the same
evidence is before us. More importantly, the discussed proceeding involved
a different patent with a different mapping of Kiuchi to its distinct claim
limitations and does not demonstrate persuasively that the “client-side
proxy” of Kiuchi is “distinguishable from” the claimed “client computer” in
claim 1 of the ’135 patent based on the evidence in the instant record. For at
least these reasons, we are not persuaded by Patent Owner’s argument.
Claim 1 recites requesting an IP address corresponding to a domain
name associated with the target computer. Patent Owner argues that Kiuchi
discloses a “URL associated with the origin server . . . not the server-side
proxy.” App. Br. 12. However, contrary to Patent Owner’s assertion,
Kiuchi discloses that the requested URL is associated with the server-side
proxy. For example, Kiuchi discloses a requested “URL” that “specifies” a
“host,” the “host” being “the requested server-side proxy [that] is registered
in the . . . network.” Kiuchi 65. We are not persuaded by Patent Owner’s
argument.
Claim 1 recites a “VPN.” Patent Owner argues that Kiuchi fails to
disclose a “VPN” because claim 1 supposedly requires the ability “to
communicate with the other devices within that same VPN,” that the VPN
must be “scalable,” and that devices in the VPN must be “able to
communicate with one another without having to discontinue an existing
connection or initiate another one.” App. Br. 13. However, Patent Owner
does not assert or demonstrate persuasively that claim 1, for example, recites
that devices must be “scalable” or must be able to communicate without
having to discontinue an existing connection or initiate another one. In any
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event, even assuming that claim 1 recites these hypothetical claim
limitations, Patent Owner does not demonstrate persuasively that the devices
of Kiuchi are not “scalable” and do not communicate without having to
discontinue an existing connection or initiate another one. Rather, Patent
Owner contends that Kiuchi discloses a device that allegedly disconnects
when the “session is finished.” App. Br. 14. One of skill in the art would
have understood that discontinuing a connection after a session is “finished”
is distinguishable from discontinuing a connection in order to communicate
at all—the two concepts being unrelated to each other.
Patent Owner argues that Kiuchi fails to disclose a “VPN” because
Kiuchi discloses devices that “do not communicate directly” and fails to
disclose devices “directly communicating.” App. Br. 14. Claim 1 does not
recite a “directly communicating.” Even assuming that claim 1 recites this
hypothetical limitation, Patent Owner does not demonstrate persuasively that
the client-side proxy and the server-side proxy (equated by the Examiner to
the client and target computers, respectively) do not “directly communicate.”
We are not persuaded by Patent Owner’s argument.
Claim 1 recites an IP address corresponding to a domain name
associated with a target computer. Patent Owner argues that Kiuchi fails to
disclose this feature because, according to Patent Owner, the IP address of
Kiuchi corresponds to the “origin server” and not the “server-side proxy,”
which is equated to the claimed “target computer” by the Examiner. See
App. Br. 15–16. We are not persuaded by Patent Owner’s argument. As
already noted above, Kiuchi discloses a requested “URL” that “specifies” a
“host,” the “host” being “the requested server-side proxy [that] is registered
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in the . . . network.” Kiuchi 65. In any event, even assuming that the
“URL” of Kiuchi corresponds directly to the “origin server,” as Patent
Owner appears to allege, Patent Owner does not assert or demonstrate
persuasively that the “URL” is not “associated with” the server-side proxy.
Regardless, Kiuchi discloses that the server-side proxy communicates with
the origin server inside the firewall. Kiuchi 66. Hence, Kiuchi’s server-side
proxy is “associated with” the origin server and its associated “URL.”
Patent Owner argues that Kiuchi fails to disclose determining whether
the DNS request is requesting access to a secure web site, as recited in claim
1, because the “server-side proxy” of Kiuchi is supposedly not a “secure web
site.” App. Br. 17. Kiuchi discloses that a “connection is established”
between the client-side proxy and the server-side proxy in which “a client-
side proxy forwards . . . requests [to the server-side proxy] in encrypted form
using C-HTTP format” and that the “server-side proxy communicates with
an origin server inside the firewall” (Kiuchi 66), such that communication
between the client-side proxy and the server-side proxy is encrypted and the
server-side proxy communicates with devices (e.g., origin server) behind the
firewall. One of skill in the art would have understood that a device that
communicates with encrypted transmissions and communicates with devices
behind a firewall would be secure.
Patent Owner argues that Kiuchi fails to disclose that the server-side
proxy is a secure web site because the server-side proxy of Kiuchi,
according to Patent Owner is not “one or more web pages at a location on
the World Wide Web.” App. Br. 17–18. Claim 1 recites a domain name
associated with at target computer. Hence, claim 1 requires that the target
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computer is associated with a domain name. Claim 1 does not also require
that the target computer is “one or more web pages at a location on the
World Wide Web.” Hence, we are not persuaded by Patent Owner’s
contention.
Patent Owner argues that Kiuchi fails to disclose a “DNS request.”
App. Br. 19. Claim 1 recites a Domain Name Service (DNS) request that
requests an IP address corresponding to a domain name associated with the
target computer. Kiuchi discloses that a “client-side proxy asks the . . .
name server whether it can communicate with the host specified in a given
URL . . . (and if) the connection is permitted, the . . . name server sends the
[requested] IP address . . . .” Kiuchi 65. In other words, Kiuchi discloses a
“request” (i.e., “asks” the server) for an IP address (i.e., the requested “IP
address” of Kiuchi) associated with the target computer (i.e., “server-side
proxy”).
Patent Owner argues that “Kiuchi does not expressly disclose the
‘DNS request’ . . . [because] Kiuchi . . . repeatedly differentiates its C-HTTP
features from DNS,” that “Kiuchi explains that the C-HTTP name service is
used ‘instead of DNS,’” that “the ‘DNS name service is not used for
hostname resolution,’” and that “a ‘DNS lookup’ is only performed after a
permission request to the C-HTTP name server fails.” App. Br. 19.
However, Patent Owner does not explain persuasively how the request of
Kiuchi (i.e., “asks” the server) differs from the claimed “DNS request” that,
like Kiuchi, requests an IP address corresponding to a desired domain name.
Dependent claim 2 recites that “steps (2) and (3) [of claim 1] are
performed at a DNS server separate from the client computer” and claim 1
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recites “automatically initiating the VPN between the client computer and
the target computer.” As the Examiner explains, Kiuchi discloses that the
“client-side proxy asks the C-HTTP name server whether it can
communicate” and “[i]f the connection is permitted, the C-HTTP name
server sends the IP address and public key of the server-side proxy and . . .
Nonce values” and that, subsequently, “the connection is established.”
Kiuchi 65, 66. In other words, Kiuchi discloses that a “client-side proxy”
sends a request to a C-HTTP name server for a secure connection with a
target computer (i.e., “asks” the name server) and, in response, the C-HTTP
name server “initiates” the connection (i.e., sends the IP address, public key,
and Nonce values prior to “the connection [being] established”).
Patent Owner argues that Kiuchi fails to disclose “automatically
initiating the VPN,” as recited in claim 2 (and claim 1) because “[t]he mere
sending of Nonce values by the C-HTTP name server to the client-side
proxy does not initiate a VPN between the client-side and server-side
proxies.” App. Br. 20. However, Patent Owner does not explain
persuasively how the “C-HTTP name server” performing a step (i.e.,
sending values) that subsequently results in “the connection [being]
established” differs from the claim feature of automatically initiating a
connection. In both cases, a step is performed by a server that results in the
subsequent formation of a secure connection between devices.
Dependent claim 3 recites returning the IP address in response to
determining that the DNS request in step (2) is not requesting access to a
secure target web site. As the Examiner points out, Kiuchi discloses a
“client-side proxy asks . . . whether it can communicate” and “[i]f the
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connection is permitted, the C-HTTP name server sends the IP address.”
Kiuchi 65. Hence, Kiuchi discloses returning a requested IP address in
response to determining that the connection is permitted (i.e., not requesting
access to a secure target web site). One of skill in the art would have
understood that a user without access to a secure site would not be permitted
to access the secure site, the user not having access to the secure site in the
first place. Since Kiuchi discloses returning the requested IP address “if the
connection is permitted,” one of skill in the art would have understood that
the “permitted” connection is not to a secure site to which the user is not
permitted access.
Regarding dependent claim 4, Patent Owner reiterates arguments that
Kiuchi supposedly fails to disclose a “client computer.” We are not
persuaded by Patent Owner’s arguments for at least the previously discussed
reasons.
Claim 13 recites a method involving a computer that maintains
“authentication tables each corresponding to one of the client computers”
and authenticating “with reference to one of the . . . authentication tables.”
As the Examiner explains, Kiuchi discloses a method involving a computer
(i.e., a “C-HTTP name server”) that sends an “IP address” corresponding to
a request. One of skill in the art would have understood that in order to send
an IP address corresponding to a request, the C-HTTP name server would
maintain the IP address data with corresponding (requested) domain names.
Otherwise, the C-HTTP name server would not maintain such data and
would not be capable of returning the desired IP address. This would be
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contrary to Kiuchi’s explicit disclosure that the desired IP address is, in fact,
returned.
Patent Owner argues that Kiuchi fails to disclose a “table,” as recited
in claim 13. App. Br. 22. As previously discussed, claim 13 requires that an
“authentication table” corresponds to one of the client computers and
authenticating is “with reference to” one of the authentication tables. Kiuchi
discloses that IP address data and corresponding (requested) domain names
are maintained by the C-HTTP name server and that authentication is with
reference to the requested domain name and corresponding IP address data.
Patent Owner does not explain a sufficient difference between the “table,” as
recited in claim 13 and the data maintained by the C-HTTP name server of
Kiuchi, both of which are maintained by a “computer” and both of which are
“referenced” in the process of authenticating.
Patent Owner appears to argue that the data maintained by Kiuchi
differs from the claimed “tables” because Kiuchi fails to disclose the precise
term “table.” We are not persuaded by Patent Owner. For a prior art
reference to anticipate in terms of 35 U.S.C. § 102, every element of the
claimed invention must be identically shown in a single reference.
However, this is not an “ipsissimis verbis” test. In re Bond, 910 F.2d 831,
832 (Fed. Cir. 1990). Therefore, it is immaterial whether or not Kiuchi
discloses the term “table” or not.
Patent Owner argues that Kiuchi fails to disclose a “central computer”
that “receives a request to establish a connection,” as recited in claim 13.
App. Br. 24. Specifically, Patent Owner argues that Kiuchi discloses a
client-side proxy “sends a request for connection to the server-side proxy”
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but that the request is not “received at the C-HTTP name server (the alleged
‘central computer’).” App. Br. 24. As previously discussed, Kiuchi
discloses that the “client-side proxy asks the C-HTTP name server whether it
can communicate . . . .” Kiuchi 65. One of skill in the art would have
understood that when a device “asks” another device, the device would be
sending a “request” to the other device. Hence, we are not persuaded by
Patent Owner’s argument that Kiuchi supposedly fails to disclose that a
request is “received at the C-HTTP name server (the alleged ‘central
computer’).”
Patent Owner argues that Martin fails to disclose an “IP address
hopping scheme,” as recited in dependent claim 6, because, according to
Patent Owner, Martin discloses that “the client chooses an address at the
outset that does not change.” App. Br. 27. Claim 6 recites an “IP address
hopping scheme” but does not appear to also recite that a client must not
choose an address at the outset that does not change. In fact, claim 6 does
not appear to recite changing an address at all. Therefore, we need not
consider whether or not Martin discloses this hypothetical claim limitation.
Patent Owner also argues that Martin discloses “selection and use of
an address” but fails to disclose “any ‘hops’ at all.” App. Br. 27. However,
Patent Owner does not explain a sufficient difference between choosing “a
random source address/port pair” (that Patent Owner alleges Martin
discloses) and the claimed IP address hopping scheme. App. Br. 27.
Dependent claim 5 recites determining whether the client computer is
authorized to resolve addresses of non secure target computers and, if not so
authorized, returning an error from the DNS request. Patent Owner argues
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that Kiuchi discloses “a ‘closed group of institutions on the Internet’ for C-
HTTP connections” and Dalton discloses “that some clients may have access
to resources outside the system.” Patent Owner further extrapolates Dalton’s
disclosure to solely include “open-access system[s]” and argues that “Kiuchi
does not contemplate an open-access system such as [systems disclosed by]
Dalton.” App. Br. 25.
To the extent that Patent Owner argues that Kiuchi teaches away from
Dalton (or vice versa), we are not persuaded by Patent Owner’s arguments
for at least the reasons set forth by Requester. 3PR Resp. Br. 10–11. For
example, Kiuchi discloses a network in which users may communicate via
secure communications. See, e.g., Kiuchi 64 (“[a] client-side proxy and
server-side proxy communicate with each other using a secure, encrypted
protocol”). Dalton also discloses network communication “that is secure
enough to implement services that are accessed over the Internet.” Dalton
Abstract. In other words, both Kiuchi and Dalton disclose network systems
in which users communicate via secure communications. Patent Owner does
not adequately explain how one network system for secure communications
(e.g., Dalton) “teaches away” from another network system for secure
communications (e.g., Kiuchi). In both cases, a network system is provided
in which users communicate securely.
To the extent that Patent Owner argues that Kiuchi discloses a “closed
system,” that Dalton discloses an “open system” and that it would not have
been obvious to one of skill in the art to have bodily incorporated the alleged
“open system” of Dalton with the alleged “closed system” of Kiuchi, we
note that “[t]he test for obviousness is not whether the features of a
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secondary reference may be bodily incorporated into the structure of the
primary reference; . . . Rather, the test is what the combined teachings of
those references would have suggested to those of ordinary skill in the art.”
In re Keller, 642 F.2d 413, 425 (CCPA 1981). Hence, we are not persuaded
by Patent Owner’s argument.
Patent Owner does not provide additional arguments in support of
claims 7, 8, 14, or 17 or arguments with respect to the Examiner’s rejection
of claim 9 under 35 U.S.C. 103(a) as unpatentable over Kiuchi and Bellovin.
App. Br. 24, 26. The Examiner did not err in rejecting claims 1–4, 7, 13, 14,
and 17 as anticipated by Kiuchi, claims 5 and 8 as unpatentable over Kiuchi
and Dalton, claim 6 as unpatentable over Kiuchi and Martin, or claim 9 as
unpatentable over Kiuchi and Bellovin.
Patent Owner argues that it would not have been obvious to one of
ordinary skill in the art to have combined the teachings of Kiuchi with that
of Solana because, according to Patent Owner, “[a]ll transmissions” of
Solana are secure and, therefore, “it would have been unnecessary to modify
the Solana system . . . to determine whether a . . . request is requesting
access to a secure web site.” App. Br. 49–50. However, the Examiner’s
rejection of the disputed claims is based on whether it would have been
obvious to one of ordinary skill in the art to have combined Kiuchi’s and
Solana’s teachings and not whether it would have been necessary to one of
ordinary skill in the art to do so. Thus, even assuming Patent Owner’s
contention to be correct that it would not have been necessary to determine if
a web site is secure, Patent Owner does not argue persuasively that it would
also not have been obvious based on references’ teachings to determine if a
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web site is secure. Given that both Kiuchi and Solana disclose secure
communications, we agree with the Examiner and Requester that it would
have been obvious to one of ordinary skill in the art to have determined if an
entity in a secure communication is secure or not. Otherwise, one of
ordinary skill in the art would not have known whether or not a network
entity is secure, not having determined if the entity is secure in the first
place, and would not have ascertained whether or not the communication
itself is secure, not having ascertained whether or not the entities involved in
the communication themselves are secure.
Patent Owner also argues that it would not have been obvious to one
of ordinary skill in the art to have combined the teachings of Kiuchi and
Solana because, according to Patent Owner, it would not have been
necessary to combine the references given that the “initiator” allegedly
“already has the . . . UNI when it sends the query.” App. Br. 48. We are
not persuaded by Patent Owner’s arguments for reasons previously
discussed above.
Patent Owner argues that Solana fails to disclose generating a DNS
request (App. Br. 48) but does not persuasively argue that Kiuchi also fails
to disclose this feature. Thus, even assuming Patent Owner’s contention that
Solana fails to disclose this feature, we are not persuaded by Patent Owner
that the combination of Kiuchi and Solana also fails to disclose this feature
for at least the reasons previously discussed above.
Patent Owner does not provide additional arguments in support of
claims 5, 8, and 18 with respect to Dalton; claim 9 with respect to Bellovin
and/or Dalton; or claim 6 with respect to Martin. The Examiner did not err
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in rejecting claims 1–5, 7, 8, and 18 as unpatentable under 35 U.S.C.
§ 103(a) over Kiuchi and Solana; claims 5, 8, and 18 as unpatentable under
35 U.S.C. § 103(a) over Kiuchi, Solana, and Dalton; claim 9 as unpatentable
under 35 U.S.C. § 103(a) over Kiuchi, Solana, Dalton, and Bellovin; and
claim 6 as unpatentable under 35 U.S.C. § 103(a) over Kiuchi, Solana, and
Martin.
In view of the above, we need not consider the propriety of the
Examiner’s non-adoption of the rejection of claims based on other grounds.
Cf. In re Gleave, 560 F.3d 1331, 1338 (Fed. Cir. 2009).

DECISION
We affirm the Examiner’s rejection of claims 1–4, 7, 13, 14, and 17
35 U.S.C. § 102 as anticipated by Kiuchi; claims 5 and 8 under 35 U.S.C.
§ 103(a) as unpatentable over Kiuchi and Dalton; claim 6 under 35 U.S.C.
§ 103(a) as unpatentable over Kiuchi and Martin; claim 9 under 35 U.S.C.
§ 103(a) as unpatentable over Kiuchi and Bellovin; claims 13–15 under 35
U.S.C. § 102 as anticipated by Solana; claims 1–5, 7, 8, and 18 under 35
U.S.C. § 103(a) as unpatentable over Kiuchi and Solana; claims 5, 8, and 18
under 35 U.S.C. § 103(a) as unpatentable over Kiuchi, Solana, and Dalton;
claim 9 under 35 U.S.C. § 103(a) as unpatentable over Kiuchi, Solana,
Dalton, and Bellovin; claim 6 under 35 U.S.C. § 103(a) as unpatentable over
Kiuchi, Solana, and Martin; claim 16 under 35 U.S.C. § 103(a) as
unpatentable over Solana and Karr; and claim 17 under 35 U.S.C. § 103(a)
as unpatentable over Solana and Denning.
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Requests for extensions of time in this inter partes reexamination
proceeding are governed by 37 C.F.R. § 1.956. See 37 C.F.R. § 41.79.
In the event neither party files a request for rehearing within the time
provided in 37 C.F.R. § 41.79, and this decision becomes final and
appealable under 37 C.F.R. § 41.81, a party seeking judicial review must
timely serve notice on the Director of the United States Patent and
Trademark Office. See 37 C.F.R. §§ 90.1 and 1.983.

AFFIRMED

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PATENT OWNER:

FINNEGAN, HENDERSON, FARABOW, GARRETT & DUNNER LLP
901 NEW YORK AVENUE, NW
WASHINGTON DC 20001-4413

THIRD PARTY REQUESTER:

SIDLEY AUSTIN LLP
2001 ROSS AVENUE
SUITE 3600
DALLAS, TX 75201

kis