International Business Machines Corporation

Patent Trials and Appeals Board

Aug 2, 2021

2020002745 (P.T.A.B. Aug. 2, 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.
15/421,426 01/31/2017 Roy F. Brabson RSW920040198US4 4734
11480 7590 08/02/2021
IBM Corporation - Patent Center
1701 North Street
B/256-3
Endicott, NY 13760
EXAMINER
SURVILLO, OLEG
ART UNIT PAPER NUMBER
2442
NOTIFICATION DATE DELIVERY MODE
08/02/2021 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):
edciplaw@us.ibm.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________

Ex parte ROY F. BRABSON
___________

Appeal 2020-002745
Application 15/421,426
Technology Center 2400
____________

Before ALLEN R. MACDONALD, ERIC B. CHEN, and
PHILLIP A. BENNETT, Administrative Patent Judges.

CHEN, Administrative Patent Judge.

DECISION ON APPEAL

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Application 15/421,426

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Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 64–69 and 74–80. Claims 1–63 and
70–73 have been cancelled. We have jurisdiction under 35 U.S.C. § 6(b).
We AFFIRM IN PART.

CLAIMED SUBJECT MATTER
The claims are directed to a load request for a connection received
from a client at a routing stack. (Abstract.)
Claims 64, 79, and 80, reproduced below, are illustrative of the
claimed subject matter, with disputed limitations in italics:
64. A computer program product comprising a
computer readable storage memory device storing therein
computer readable program code for load balancing using
Mobile Internet Protocol (IP) Version 6, the computer readable
program code, which when executed by a computer hardware
system, causes the computer hardware system to:
receive, from a client, a request for a Transmission
Control Protocol (“TCP”) connection at a routing stack within
a Sysplex Distributor of an Internet Protocol (IP) workload
balancing system; and
in response to the request for the TCP connection
received in the routing stack, select a target stack for receiving
the TCP connection for a dynamic virtual Internet protocol
address (DVIPA), determine both if Mobile IP Version 6 route
optimizations have been enabled for the routing stack based
upon a presence of a mobility header in the request indicating
that a copy of a Care-of Test message should be forwarded to
the routing stack, and also if the selected target stack supports
Mobile IP Version 6 route optimizations, and if not, transmit a

1 We use the word “Appellant” to refer to “applicant” as defined in
37 C.F.R. § 1.42(a). Appellant identifies the real party in interest as
International Business Machines Corporation. (Appeal Br. 2.)
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message to the client with the selected stack and subsequently
communicating with the client so as to route subsequent
requests in the routing stack, but if so, insert the selected target
stack into a Mobile IP Version 6 Binding Update message, and
transmit the Mobile IP Version 6 Binding Update message to
the client so that the client subsequently communicates directly
with the selected target stack without communicating with the
routing stack.

79. A computer system comprising:
a processor(s) set;
a storage device; and
a routing stack stored in the memory and executable by
the processor set, with the routing stack including data and
instructions to cause the processor(s) set to perform at least the
following operations:
receiving, from a client and over a communication
network, a request for a Transmission Control Protocol (“TCP”)
connection,
responsive to the receipt of the request, selecting a
selected target stack for receiving the TCP connection,
determining that Mobile IP route optimizations have been
enabled for the routing stack,
determining that the selected target stack supports the
Mobile IP route optimizations,
responsive to the determination that Mobile IP route
optimizations have been enabled for the routing stack, and
further responsive to the determination that the selected target
stack supports the Mobile IP route optimizations:
inserting the selected target stack into a Mobile IP
Binding Update message, and
transmitting the Mobile IP Binding Update
message to the client, and
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establishing the requested TCP connection with
the client so that the client uses the Mobile IP Binding
Update message to communicate directly with the
selected target stack without communicating through the
routing stack.

80. A computer system comprising:
a processor(s) set;
a storage device; and
a routing stack stored in the memory and executable by
the processor set, with the routing stack including data and
instructions to cause the processor(s) set to perform at least the
following operations:
receiving, from a client and over a communication
network, a request for a Transmission Control Protocol (“TCP”)
connection,
responsive to the receipt of the request, selecting a
selected target stack for receiving the TCP connection,
determining that Mobile IP route optimizations have been
enabled for the routing stack,
determining that the selected target stack does not
support the Mobile IP route optimizations,
responsive to the determination that the selected target
stack does not support the Mobile IP route optimizations:
transmitting, to the client and over the
communication network, a message with the selected
stack, and
communicating with the client with the
communication including routing subsequent requests in
the routing stack.
REJECTIONS
Claims 64–69 and 74–80 stand rejected under 35 U.S.C. § 112(a) as
failing to comply with the written description requirement.
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Claims 79 and 80 stand rejected under 35 U.S.C. § 112(b) as
indefinite for failing to particularly point out and distinctly claim the subject
matter which the inventor or a joint inventor regards as the invention
The Examiner has withdrawn the rejection of claims 64–69 and 74–78
under 35 U.S.C. § 112(b). (Pre-Appeal Conference Dec. at 4–5, mailed
Nov. 6, 2019.)
The Examiner has withdrawn the rejection of claim 80 under
35 U.S.C. § 102 and the rejection of claims 64–69 and 74–79 under 35
U.S.C. § 103. (Id. at 6.)

OPINION
§ 112(a) Rejection—Written Description
Claims 64–69 and 74–78
We are persuaded by Appellant’s arguments (Appeal Br. 5; see also
Reply Br. 2) that the limitations “receive, from a client, a request for a
Transmission Control Protocol (“TCP”) connection at a routing stack” and
“indicating that a copy of a Care-of Test message should be forwarded to the
routing stack,” as recited in independent claim 64, comply with 35 U.S.C.
§ 112(a).
The Examiner found that “[b]ased on the claim language construction
. . . a request for TCP connection received at the routing stack (initial
request) contains a presence mobility header indicating that a copy of a
Care-of Test message should be forwarded to the routing stack” (Ans. 3–4),
however, “the specification and drawings depict a request for TCP
connection as a completely separate communication from a message
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indicating that a copy of a Care of Test message should be forwarded to the
routing stack” (id. at 4; see also Final Act. 5–6). We do not agree.
Independent claim 64 recites the following: (i) “receive, from a
client, a request for a Transmission Control Protocol (“TCP”) connection at
a routing stack”; (ii) “determine both if Mobile IP Version 6 route
optimizations have been enabled for the routing stack based upon a presence
of a mobility header in the request indicating that a copy of a Care-of Test
message should be forwarded to the routing stack”; and (iii) “if the selected
target stack supports Mobile IP Version 6 route optimizations, and if not,
transmit a message to the client” (emphases added). Thus, independent
claim 64 includes a conditional limitation with two possible outcomes—
either “if Mobile IP Version 6 route optimizations have been enabled” or “if
not.”
Moreover, the determination “if Mobile IP Version 6 route
optimizations have been enabled” is “based upon a presence of a mobility
header in the request indicating that a copy of a Care-of Test message should
be forwarded.” Thus, because one possible outcome is that Mobile IP
Version 6 route optimizations have not been enabled, claim 64 does not
necessarily require the recited “a request for a Transmission Control
Protocol (“TCP”) connection at a routing stack” to include “a presence of a
mobility header in the request indicating that a copy of a Care-of Test
message should be forwarded.”
Additionally, Appellant’s Specification discloses the following:
Some embodiments of the present invention provide
methods, systems and computer program products for load
balancing using Mobile Internet Protocol (IP) Version 6. A
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request for a connection is received from a client at a routing
stack.
(Spec. ¶ 7 (emphasis added).)
In further embodiments of the present invention, a Care-
of Test message may be received at the target stack from the
client. The Care-of Test message may include a mobility
header indicating that a copy of the Care-of Test message
should be forwarded to the routing stack. The copy of the Care-
of Test message may be transmitted to from the target stack to
the routing stack. The connection may be established at the
client between the client, the routing stack and the target stack
so as to allow direct communication between the client and the
target stack. An indication may be transmitted from the client to
the routing stack that the connection has been established.
(Spec. ¶ 11 (emphasis added).)
Thus, because the Specification discloses that “[a] request for a
connection is received from a client at a routing stack” (id. ¶ 7) and “[t]he
copy of the Care-of Test message may be transmitted to from the target stack
to the routing stack” (id. ¶ 11), the Specification provides written description
support for the limitations “receive, from a client, a request for a
Transmission Control Protocol (“TCP”) connection at a routing stack” and
“indicating that a copy of a Care-of Test message should be forwarded to the
routing stack,” respectively.
Accordingly, we are persuaded by Appellant’s arguments, as follows:
Specifically, as stated at paragraph [0007] of the original
specification, a request is provided from the client to the routing
stack. . . . At paragraph [0011] of the original specification, a
teaching is present that a Care-of-Test message is received at
the target stack from the client and that the message includes a
mobility header that indicates that a copy of the Care-of-Test
message should be forward to the routing stack. Therefore, the
request received by the routing stack is “forwarded” to the
target stack in which the mobility header is identified and
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processed in order to determine if a copy of the Care-of-Test
message is to be forwarded to the routing stack.
(Appeal Br. 5; see also Reply Br. 2.)
Thus, we do not agree with the Examiner that the Specification fails to
provide written description support for the limitations “receive, from a
client, a request for a Transmission Control Protocol (“TCP”) connection at
a routing stack” and “indicating that a copy of a Care-of Test message
should be forwarded to the routing stack.”
Therefore, we do not sustain the rejection of independent claim 64
under 35 U.S.C. § 112(a). Claims 65–69 and 74–78 depend from claim 64.
We do not sustain the rejection of claims 65–69 and 74–78 under 35 U.S.C.
§ 112(a) for the same reasons discussed with respect to independent claim
64.

Independent Claim 79
We are persuaded by Appellant’s arguments (Reply Br. 5) that the
limitation “establishing the requested TCP connection with the client so that
the client uses the Mobile IP Binding Update message to communicate
directly with the selected target stack without communicating through the
routing stack,” as recited in independent claim 79, complies with 35 U.S.C.
§ 112(a).
The Examiner found that “the limitation ‘establishing the requested
TCP connection with the client so that the client uses the Mobile IP Binding
Update message to communicate directly with the selected target stack
without communicating through the routing stack’ is not the functionality
performed by the routing stack because the claim requires ‘without
communicating through the routing stack’” and the “claim appears to
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describe an impossible scenario where connection is established without
communicating.” (Final Act. 6; see also Ans. 5.) We do not agree.
Appellant’s Figure 2, which illustrates a block diagram of system 200,
including client 205, routing stack 210, and first, second and third target
stacks 220, 230 and 240 (Spec. ¶ 60), is reproduced below:

In particular, Figure 2 illustrates that client 205 can bypass routing stack
210, and communicate directly with first, second, and third target stacks 220,
230, and 240, via “path B.” Moreover, Appellant’s Specification discloses
the following:
To provide load balancing using Mobile Internet Protocol
(IP) Version 6, the routing stack 210 may be configured to
receive a request for a connection from the client 205 over a
connection A. A Mobile IP Version 6 “Binding Update
message”, discussed above, may be transmitted to the client 205
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responsive to the received request for the connection. The
Binding Update message may identify a selected target stack
(220, 230, 240) with which the client 205 may communicate
directly, bypassing the routing stack according to some
embodiments of the present invention discussed herein. . . .
Thus, the client 205 may communicate directly with the selected
target stack 240 over path B instead of through the routing
stack 210 using paths A.
(Spec. ¶ 61 (emphasis added).)
Thus, because Appellant’s Specification discloses that client 105 can
also communicate directly with target stack directly (i.e., Path B in Figure 2)
and thus, bypassing routing stack 210, the Specification provides written
description support for the limitation “client . . . communicate[s] directly
with the selected target stack without communicating through the routing
stack.”
Accordingly, we are persuaded by Appellant’s arguments, as follows:
as support by Paragraph [0061] of the Appellants’ specification,
the routing stack can include instructions that “establish[] the
requested TCP connection with the client so that the client uses
the Mobile IP Binding Update message to communicate
directly with the selected target stack without communicating
through the routing stack,” as recited in Appellants’ claim 79.
(Reply Br. 5.)
Thus, we do not agree with the Examiner that the Specification fails to
provide written description support for the limitation “establishing the
requested TCP connection with the client so that the client uses the Mobile
IP Binding Update message to communicate directly with the selected target
stack without communicating through the routing stack.”
Therefore, we do not sustain the rejection of independent claim 79
under 35 U.S.C. § 112(a).
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Independent Claim 80
We are persuaded by Appellant’s arguments (Reply Br. 6) that the
limitations “determining that the selected target stack does not support the
Mobile IP route optimizations” and “responsive to the determination that the
selected target stack does not support the Mobile IP route optimizations:
transmitting, to the client and over the communication network, a message
with the selected stack, and communicating with the client with the
communication including routing subsequent requests in the routing stack,”
as recited in independent claim 80, comply with 35 U.S.C. § 112(a).
The Examiner found that
the limitations “determining that the selected target stack does
not support the Mobile IP route optimizations, responsive to the
determination that the selected target stack does not support the
Mobile IP route optimizations: transmitting, to the client and
over the communication network, a message with the selected
stack, and communicating with the client with the
communication including routing subsequent requests in the
routing stack” are not supported by the specification in
connection with the routing stack
and “Applicants failed to identify relevant portions of the specification and
corresponding drawings that support these functions in the situation when
the selected target stack is determined not to support the Mobile IP
optimization.” (Final Act. 6–7; see also Ans. 6–7.) We do not agree with
the Examiner.
Appellant’s Specification discloses the following:
It will be understood that embodiments of the present
invention discussed herein may be implemented if Mobile IP
Version 6 route optimizations have been enabled for the DVIPA
and the target stack supports Mobile IP Version 6 route
optimizations. If the target stack does not support Mobile IPv6
route optimizations, or if Mobile IP Version 6 route
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optimizations are not enabled for the DVIPA, the routing stack
may continue to select target stacks for new connection
requests using conventional methods known to those having
skill in the art.
(Spec. ¶ 72 (emphasis added).)
Thus, because the Specification discloses that “the present invention
discussed herein may be implemented if Mobile IP Version 6 route
optimizations have been enabled” (id.), the Specification provides written
description support for the limitation “determining that the selected target
stack does not support the Mobile IP route optimizations.” Similarly,
because the Specification discloses that “[i]f the target stack does not
support Mobile IPv6 route optimizations, or if Mobile IP Version 6 route
optimizations are not enabled for the DVIPA, the routing stack may continue
to select target stacks for new connection requests” (id.), the Specification
provides written description support for the limitation “responsive to the
determination that the selected target stack does not support the Mobile IP
route optimizations: transmitting, to the client and over the communication
network, a message with the selected stack, and communicating with the
client with the communication including routing subsequent requests in the
routing stack.”
Accordingly, we are persuaded by Appellant’s arguments, as follows:
there is explicit support [in paragraph 72] for “determining that
the selected target stack does not support the Mobile IP route
optimizations, responsive to the determination that the selected
target stack does not support the Mobile IP route optimizations:
transmitting, to the client and over the communication network,
a message with the selected stack, and communicating with the
client with the communication including routing subsequent
requests in the routing stack,” as disclosed in Appellants’ claim
80.
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(Reply Br. 6.)
Thus, we do not agree with the Examiner that the Specification fails to
provide written description support for the limitations “determining that the
selected target stack does not support the Mobile IP route optimizations” and
“responsive to the determination that the selected target stack does not
support the Mobile IP route optimizations: transmitting, to the client and
over the communication network, a message with the selected stack, and
communicating with the client with the communication including routing
subsequent requests in the routing stack.”
Accordingly, we do not sustain the rejection of independent claim 80
under 35 U.S.C. § 112(a).

§ 112(b) Rejection—Indefiniteness
Independent Claim 79
We do not sustain the rejection of independent claim 79 under 35
U.S.C. § 112(b) for the same reasons discussed with the rejection of
independent claims 79 under 35 U.S.C. § 112(a).

Independent Claim 80
We are unpersuaded by Appellant’s arguments (Reply Br. 8) that the
limitation “communicating with the client with the communication including
routing subsequent requests in the routing stack,” as recited in independent
claim 80, complies with 35 U.S.C. § 112(b).
The Examiner concluded that “[t]he last claimed step is ambiguous
because it is unclear what ‘the communication’ refers to” and “it is unclear
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what it means.” (Final Act. 7–8.) We agree with the Examiner’s
conclusion.
Independent claim 80 recites “communicating with the client with the
communication including routing subsequent requests in the routing stack.”
Because claim 80 recites “the communication,” and the claim provides no
earlier recitation of “a communication,” the claim is unclear as to what
element “the communication” refers.
Appellant argues that “the client is allowed to communicate directly
with a target stack [as disclosed in paragraph 73], therefore, it is only logical
that a communication would be communicated directly with that target
stack” and “assert[s] that is unequivocally clear what the communication in
Appellants’ claim 80 is.” (Reply Br. 8.) However, Appellant’s argument is
merely a conclusory statement, which does not adequately rebut the
Examiner’s conclusion that “the communication” is indefinite.
Thus, we sustain the rejection of independent claim 80 under 35
U.S.C. § 112(b).

CONCLUSION
The Examiner’s decision rejecting claims 64–69 and 74–80 under 35
U.S.C. § 112(a) is reversed.
The Examiner’s decision rejecting claim 79 under 35 U.S.C. § 112(b)
is reversed.
The Examiner’s decision rejecting claim 80 under 35 U.S.C. § 112(b)
is affirmed.

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DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C. § Reference(s)/
Basis
Affirmed Reversed
64–69, 74–
80
112(a) Written
Description
64–69, 74–
80
79, 80 112(b) Indefiniteness 80 79
Overall
Outcome
80 64–69, 74–
79

TIME PERIOD FOR RESPONSE
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 IN PART