Ex Parte LI

Patent Trial and Appeal Board

Mar 24, 2014

10756152 (P.T.A.B. Mar. 24, 2014)

UNITED STATES PATENT AND TRADEMARK OFFICE
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BEFORE THE PATENT TRIAL AND APPEAL BOARD
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Ex parte RUI LI
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Appeal 2011-004660
Application 10/756,152
Technology Center 2400
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Before ALLEN R. MacDONALD, LYNNE E. PETTIGREW, and
MIRIAM L. QUINN, Administrative Patent Judges.

QUINN, Administrative Patent Judge.

DECISION ON APPEAL
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Appellant appeals under 35 U.S.C. § 134(a) (2002) from a rejection of
claims 1-36 and 43-52. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM.

STATEMENT OF THE CASE
The invention relates generally to hypertext transfer protocol (HTTP)
communication within a network, and, more particularly, to techniques for
extending the keep-alive time of HTTP persistent connections. Spec. 1, 4-7.
Details of the appealed subject matter are recited in illustrative claim 1
reproduced below from the Claims Appendix of the Appeal Brief:
1. A method, comprising:
at a network device, providing a hypertext transfer
protocol (HTTP) client-side connection and a HTTP server-
side connection;
receiving at said network device via said client-side
connection a communication that signals said server-side
connection to close; and
maintaining persistent, by said network device, at least
the server-side connection in response to said communication
received via said client-side connection.

As evidence of unpatentability of the claimed subject matter, the
Examiner relies on the following references at pages 3 to 11 of the Answer:
Craig US 7,031,314 B2 April 18, 2006
Peiffer US 7,055,028 B2 May 30, 2006
Susai US 6,954,780 B2 Oct. 11, 2005
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The Examiner provides the following grounds of rejection, of which
Appellant seeks review:
a) Claims 1-5, 9-34, 36, 43-50, and 52 stand rejected under 35 U.S.C.
§ 103(a) as being unpatentable over Craig and Peiffer (Ans. 4-10);
and
b) Claims 6-8, 35, and 51 stand rejected under 35 U.S.C. § 103(a) as
being unpatentable over Craig, Peiffer, and Susai (Ans. 10-11).
ANALYSIS
We have reviewed the Examiner’s rejections in light of Appellant’s
arguments. Further, we have reviewed the Examiner’s response to
Appellant’s arguments and Appellant’s reply to the Examiner’s response.
Appellant raises various arguments on appeal directed at the findings
and conclusions of the Examiner in connection with limitations recited in
independent claim 1 and dependent claims 9 and 11. Specifically, for
independent claims 14, 22, 27, and 31, Appellant makes the same arguments
propounded with regard to independent claim 1. App. Br. 13-14, 17-18, 21-
22, and 24-25. For dependent claims 20, 25, 28, and 32, Appellant’s
contentions are similar to those made with respect to dependent claim 9. Id.
at 10-11, 15-16, 18-19, 22-23, and 27-28. And for dependent claims 21, 26,
29, and 33, Appellant challenges the same findings and conclusions made by
the Examiner in connection with dependent claim 11. Id. at 12-13, 16-17,
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20, 23-24, and 27-28. The remaining rejected claims are not argued
separately.1
Appellant’s contentions may be summarized as follows:
a) Did the Examiner err in rejecting the pending independent claims
because neither Craig nor Peiffer teaches “maintaining persistent
. . . the server-side connection” limitation?
b) Did the Examiner err in finding that Craig teaches the limitation of
“modifying . . . a header”?
c) Did the Examiner err in finding that Peiffer teaches “changing . . .
a HTTP version value . . . to another HTTP version value that is
recognizable by a server”?
We address each of Appellant’s contentions in turn.
A. Whether Craig or Peiffer Teaches “Maintaining Persistent”
Claim 1 recites “maintaining persistent, by said network device, at
least the server-side connection in response to said communication received
via said client-side connection.” Appellant argues that Craig does not teach
the limitation because Craig teaches to close the server-side connection in
response to handshakes and messages that signal the server to close a
connection. App. Br. 9; Reply 4. Appellant further argues that Peiffer does
not teach the limitation either because the persistent connections in Peiffer

1 Appellant’s argument for dependent claims 2-8, 10, 12, 13, 15-19,
23, 24, 30, 34-36, and 43-52 merely reference the arguments made with
respect to the claim(s) from which they depend (App. Br. 10, 12-14, 18, 24,
and 28). Therefore, except for our ultimate decision, these claims are not
discussed further herein. See 37 C.F.R. § 41.37(c)(1)(vii)(2011).
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are maintained open “unless explicitly commanded to close.” App. Br. 10.
We are not persuaded by either of Appellant’s arguments.
First, Appellant’s argument concerning Craig fails to address the
Examiner’s finding that Craig discloses the limitation because the server-
side connection does not close until receiving a message (FIN message). See
Ans. 12 (citing Craig, fig. 4, items 450, 455); Craig, fig. 4 (depicting that the
server closes the “server-side connection” upon receiving a FIN message,
not the close message from the client). That is, after receiving the “close”
message, the server-side connection does not close for a time. The claims do
not require any specific length of time for “maintaining persistent.”
Therefore, Appellant’s argument fails to show error in the Examiner’s
finding that Craig teaches the limitation.
Second, Appellant’s argument directed at Peiffer ignores relevant
teachings of persistent connections that the Examiner relied on in the
rejection. For example, the Examiner relies on Peiffer’s description of the
persistent connections described in column 10, lines 33-57 and Figure 7 as
evidence that Peiffer teaches maintaining persistent the server-side
connections. We are persuaded that the Examiner did not err in this finding.
Figure 7 illustrates that once a connection with a server is established, the
connection is not closed. See also Peiffer, col. 10, ll. 43-45 (describing
Figure 7). Appellant’s argument, instead, focuses on earlier paragraphs, in
column 9, where Peiffer describes typical server-side connections affected
by a command to close (see Reply 4), but ignores the remainder of Peiffer
that confirms the departure from typical connections in that secure server-
side connections are not torn down and reestablished for each client (see
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col. 16, ll. 11-13 (emphasis added)). Accordingly, we are not persuaded that
the Examiner erred in finding that Peiffer teaches the “maintaining
persistent” limitation.
B. Whether Craig Teaches “Modifying . . . a Header” Limitation.
Appellant contends that the Examiner erred in rejecting claim 9
because Craig does not teach two limitations: (1) “maintaining persistent at
least the server-side connection;” and (2) “modifying . . . a header . . . to
cause a server to ignore the modified header.” App. Br. 11-12. Claims 20,
25, 28, and 32 recite similar limitations. We do not agree with Appellant’s
contentions.
The first contention—whether Craig or Peiffer discloses “maintaining
persistent”—was dealt with above with regards to claim 1. With respect to
the second contention—regarding the “ignore the modified header”
limitation—the Examiner relies on Craig’s teachings of a mask applied to a
packet header to determine if it matches a classification rule. See Craig, col.
7, l. 66  col. 8. l. 6 (cited in the Examiner’s Answer at 14); see also Craig,
col. 11, ll. 32-37 (cited at page 6 in the Examiner’s Rejection mailed Aug. 5,
2009). For example, Craig teaches that if the masked packet header does not
match a rule (corresponding to the recited “unrecognizable format”), the
packet is terminated (corresponding to “ignore the modified header”). See
Craig, col. 11, ll. 45-48 (cited in Ans. 14). In contrast, Appellant argues that
when it finds a match, Craig opens a new separate connection, and that such
action by Craig is the opposite of the claim requirement that the server
“ignore” the modified header. App. Br. 11-12. Appellant’s argument,
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however, does not address the Examiner’s findings that when there is no
match, Craig ignores the packet (and, therefore, the modified header)
because Craig terminates the packet. Ans. 14.
In its reply, Appellant further argues that the order in which Craig
handles the modification and classification differs from the order in which
claim 9 recites “modifying . . . a header.” Reply 5-6. In particular,
Appellant contends that claim 9 requires that the format be rendered
unrecognizable after modification of the header, but that Craig proceeds
without modification after determining that the header format is
unrecognizable. Id. These arguments are not persuasive because whether
Craig may modify a packet’s header after the mask and classification is not
commensurate with the scope of the claim, which does not require any
action after ignoring the packet. The Examiner has pointed to Craig’s
masking and classification matching before dropping the packet and
Appellant has not addressed whether the recited “modifying” reads on
Craig’s masking of a header.
Accordingly, Appellant has not persuaded us of error in the
Examiner’s finding concerning the “modifying . . . a header” limitation, as
recited in claim 9, and similarly recited in claims 20, 25, 28 and 32.
C. Whether Peiffer Teaches the “Changing” Limitation
Claim 11 recites “changing . . . a HTTP version value indicated in the
communication to another HTTP version value that is recognizable by a
server . . . as being associated with a persistent connection.” Claims 21, 26,
29, and 33 recite a similar limitation. Appellant contends that the Examiner
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erred in rejecting claim 11 because Peiffer “mentions nothing” with respect
to changing a HTTP version value. App. Br. 13. This argument does not
address the Examiner’s finding that Peiffer implies changing to a value that
is recognizable by the server because Peiffer evaluates the type of request to
match the proper version of HTTP request with the appropriate server-side
socket. Ans. 15 (citing Peiffer, col. 9, ll. 37-48). The Examiner’s rejection
is not based on an express disclosure of changing a value. Therefore, an
argument that the reference does not “mention” changing is not responsive
to the rejection.
In its reply, Appellant argues that Peiffer’s routing of a request to the
appropriate socket sends the request without any “changing.” Reply 7. This
reply argument is not commensurate with the scope of the claim. Claim 11
requires that the network device change a value in the received
communication to another value. The claim, however, does not specify that
the change must be implemented in the packet header or other specific data
structure. Therefore, under the broadest reasonable interpretation of the
claim, the socket determination in Peiffer does not have to change either the
packet header or the request to meet the “change” limitation. The Examiner
has found that matching Peiffer’s sockets to the server that can handle the
specific type of HTTP request implies a change, by the network device, from
one value to another. Ans. 15. Appellant’s arguments do not persuade us
that the finding is in error.
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CONCLUSION
We conclude that Appellant has not shown error in the Examiner’s
findings and conclusions that the combination of Craig and Peiffer renders
obvious the subject matter of claims 1, 9, and 11. Therefore, we sustain the
rejection of claims 1, 9, and 11 under 35 U.S.C. § 103(a). We group
independent claims 14, 22, 27, and 31 with independent claim 1. We group
dependent claims 20, 25, 28, and 32 with dependent claim 9. We group
dependent claims 21, 26, 29, and 33, with dependent claim 11. And we
group dependent claims 2-8, 10, 12, 13, 15-19, 23, 24, 30, 34-36, and 43-52,
not argued separately, with the claim(s) from which they depend.
DECISION
We affirm the Examiner’s decision to reject claims 1-36 and 43-52.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv).

AFFIRMED

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