Ex Parte Garg et al

Board of Patent Appeals and Interferences

Aug 9, 2011

10662728 (B.P.A.I. Aug. 9, 2011)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte SACHIN GARG and MARTIN KAPPES
____________

Appeal 2009-011368
Application 10/662,728
Technology Center 2400
____________

Before JAY P. LUCAS, JOHN A. JEFFERY, and JAMES R. HUGHES,
Administrative Patent Judges.

JEFFERY, Administrative Patent Judge.

DECISION ON APPEAL
Appellants appeal under 35 U.S.C. § 134(a) from the Examiner’s
rejection of claims 1-10. We have jurisdiction under 35 U.S.C. § 6(b). We
affirm.

STATEMENT OF THE CASE
Appellants’ invention reduces the likelihood of node congestion in
telecommunications networks by dropping certain protocol data units. See
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generally Spec. ¶¶ 0013-15. Claim 1 is illustrative with key disputed
limitations emphasized:
1. A method comprising:
receiving a first plurality of protocol data units at a first
input, wherein all of said first plurality of protocol data units
are en route to a first congestible node;
maintaining at a protocol-data-unit excisor a first queue
for said first plurality of protocol data units;
receiving at said protocol-data-unit excisor a flow control
signal that indicates whether said first congestible node is ready
to receive one or more of said protocol data units from said first
queue; and
selectively dropping, at said protocol-data-unit excisor,
one or more of said protocol data units based on a first metric of
said first queue.

RELATED APPEAL
This appeal is related to another appeal in connection with
Application No. 10/662,724 (Appeal No. 2009-007754) (Br. 5, 21; Ans.
2)—an appeal that has been decided. See Ex parte Garg, No. 2009-007754,
2010 WL 5137104 (BPAI 2010) (non-precedential) (reversing Examiner’s
anticipation rejection over prior art different than that cited in the present
appeal).

CITED REFERENCES
The Examiner relies on the following as evidence of unpatentability:
Erimli US 6,405,258 B1 June 11, 2002
Barker US 2002/0131365 A1 Sept. 19, 2002
Muller US 6,650,640 B1 Nov. 18, 2003
(filed Mar. 1, 1999)
Yu US 7,031,341 B2 Apr. 18, 2006
(filed Mar. 27, 2001)
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THE REJECTIONS
1. The Examiner rejected claims 1, 2, 4-6, and 8-10 under 35 U.S.C.
§ 103(a) as unpatentable over Muller, Erimli, and Barker. Ans. 3-9.1
2. The Examiner rejected claims 3 and 7 under 35 U.S.C. § 103(a) as
unpatentable over Muller, Erimli, Yu, and Barker. Ans. 9.

THE OBVIOUSNESS REJECTION OVER MULLER, ERIMLI, AND BARKER
Regarding representative claim 1, the Examiner finds that Muller
discloses every recited feature including receiving protocol data units at a
first input, where all of these data units are en route to a first congestible
node, which the Examiner equates to Muller’s Network Interface Circuit
(NIC). Ans. 3-5, 10-11. The Examiner finds that Muller does not disclose
(1) the node sending a ready to receive signal for protocol data units, and (2)
adding a traffic controlling data engine for congestion management, but cites
Erimli and Barker to cure these respective deficiencies in concluding that the
claim would have been obvious. Id.
Appellants argue that neither Muller2 nor Erimli teach or suggest
receiving a first plurality of protocol data units at a first input, where all of
these data units are en route to a first congestible node as claimed—a
limitation that is said to require only one node. Br. 15. The issue before us,
then, is as follows:

1 Throughout this opinion, we refer to the Appeal Brief filed April 28, 2008
and the Examiner’s Answer mailed July 8, 2008.
2 Although Appellants refer to this reference as “Miller” (Br. 14-15), we
nonetheless refer to this reference by its proper spelling (i.e., Muller) for
clarity.
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ISSUE
Under § 103, has the Examiner erred in rejecting claim 1 by finding
that Muller, Erimli, and Barker collectively would have taught or suggested
receiving protocol data units at a first input, where all these data units are en
route to a first congestible node?

FINDINGS OF FACT (FF)
1. “[A] ‘protocol data unit’ is defined as the data object that is
exchanged by entities. . . . A ‘frame,’ a ‘packet,’ and a ‘datagram’ are typical
protocol data units.” Spec. ¶ 0003.
2. “[A] ‘congestible node’ is defined as a network node (e.g. a
switch, router, access point, etc.) that is susceptible to dropping protocol data
units.” Spec. ¶ 0008.
3. We adopt the Examiner’s factual findings regarding Muller’s
disclosure as our own. Ans. 10-11.
4. Muller’s NIC 100 processes communication packets exchanged
between network 102 and a host computer system. A packet may be
received at NIC 100 from network 102 by a Medium Access Control (MAC)
module that (1) performs low-level packet processing and error checking;
(2) detects packet fragments and over-sized packets; (3) removes the layer-
one preamble; etc. Muller, col. 1, ll. 50-54; col. 8, ll. 25-39; Fig. 1A.
Muller’s NIC is detailed in Figure 1A reproduced below:
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Muller’s NIC in Figure 1A

5. The NIC’s Input Port Processing (IPP) module 104 then receives
the packet and stores the entire packet in packet queue 116 as received from
the MAC module or network. Also, part of the packet is copied into header
parser 106. Muller, col. 8, ll. 40-43; Fig. 1A.
6. Muller notes that in the illustrated embodiment, a communication
flow comprises one or more datagram packets from one source entity to one
destination entity. Muller, col. 8, ll. 64-66; Fig. 1A.

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ANALYSIS
This appeal turns on one question: Does Muller teach or suggest
receiving “protocol data units” at a first input, where all these data units are
en route to a first “congestible node”? Since the Examiner’s reliance on
Barker is undisputed (see Br. 15), and the Examiner relies on Erimli for
another undisputed aspect of claim 1 (Ans. 4), we confine our discussion to
Muller.
The Examiner maps Muller’s NIC and its modules to the recited “first
congestible node.” Ans. 10-11. This finding reasonably comports with
Appellants’ definition of the term, namely a network node (e.g., a switch,
router, access point, etc.) that is susceptible to dropping “protocol data units”
(e.g., packets). See FF 1-2.
Although the Examiner does not squarely identify the “first input” in
Muller, the Examiner nonetheless indicates that packets destined for
Muller’s host computer system must pass through the “congestible node,”
namely the NIC. Ans. 11. Certainly, the NIC has an input that receives
packets; indeed, the large arrow in Figure 1A that points from network 102
to the NIC’s input port processing module indicating the flow of data into
the NIC confirms this point. FF 4. In any event, Muller’s unillustrated
MAC module functions as such an input, for it receives packets at the NIC
for various processing and error-checking functions before the packets are
sent to other NIC modules. See FF 4-5.
Therefore, Muller at least suggests that all packets received at the
NIC’s input are en route to the NIC (i.e., the “congestible node”) for
processing before being sent to their ultimate destination, namely the host
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computer. See FF 4. That Muller indicates that packets flow from one
source entity to one destination entity (FF 6) only bolsters this conclusion.
To the extent that Appellants argue that Muller routes packets to more
than one congestible node, and not “exactly one node” (Br. 15), is not only
unsupported on this record, but is not commensurate with the scope of claim
1. Although the claim recites that all received protocol data units are en
route to “a” first congestible node, that hardly means that they must be
routed to only one such node. See KCJ Corp. v. Kinetic Concepts, Inc., 223
F.3d 1351, 1356 (Fed. Cir. 2000) (noting the indefinite article “a” or “an”
means “one or more” in open-ended claims containing the transitional term
“comprising”). So even if we were to assume that Muller routes packets to
multiple NICs (a finding that has not been made on this record in any event),
the scope and breadth of claim 1 reciting routing all protocol data units to
“a” first congestible node does not preclude routing those units to additional
nodes.
We are therefore not persuaded that the Examiner erred in rejecting
representative claim 1, and claims 2, 4-6, and 8-10 not separately argued
with particularity.

THE OBVIOUSNESS REJECTION OVER MULLER, ERIMLI, YU, AND BARKER
We also sustain the Examiner’s obviousness rejection of claims 3 and
7. Ans. 9. Appellants have not particularly pointed out errors in the
Examiner’s reasoning to overcome the Examiner’s conclusion of
obviousness for these claims, but rather indicate that Yu fails to cure the
independent claims’ deficiencies. Br. 16. We are not persuaded by these
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arguments, however, for the reasons previously discussed. The rejection is
therefore sustained.

CONCLUSION
The Examiner did not err in rejecting claims 1-10 under § 103.

ORDER
The Examiner’s decision rejecting claims 1-10 is affirmed.
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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