Ex Parte Luby

Board of Patent Appeals and Interferences

Oct 4, 2011

09587542 (B.P.A.I. Oct. 4, 2011)

UNITED STATES PATENT AND TRADEMARK OFFICE
_____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
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Ex parte MICHAEL G. LUBY
_____________

Appeal 2009-011058
Application 09/587,542
Technology Center 2400
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Before, ROBERT E. NAPPI, CARLA M. KRIVAK, and
DAVID M. KOHUT, Administrative Patent Judges.

KOHUT, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134(a) of the final
rejection of claims 1-12. We have jurisdiction under 35 U.S.C. § 6(b).
We reverse the Examiner’s rejection of these claims.

Appeal 2009-011058
Application 09/587,542

2
INVENTION
The invention is directed to apparatus and method for managing
multicasting network traffic by reducing the send rate over time. See Spec.
6-7. Claim 1 is representative of the invention and is reproduced below:
1. In a network supporting packet multicasting from a
sender into the network, where hosts join and leave a multicast
group by sending join and leave messages, respectively, to an
access device in the network, an improvement comprising:
a plurality of layers, wherein a layer is a logical channel
that carries packets for the multicast group;
logic for distributing multicast traffic from the sender
over the plurality of layers according to a sending rate
associated with each of the plurality of layers;
logic for accepting join and leave messages at the
access device from the hosts, wherein the join and leave
messages are associated with one or more layers of the
plurality of layers; and
logic for reducing the sending rate of at least one of the
plurality of layers over time independent of receiver
feedback.

REFERENCES
Lorenzo Vicisano, et al., TCP-like Congestion Control for Layered
Multicast Data Transfer, IEEE Infocom ’98 (San Francisco, CA, Mar. 29-
Apr. 2, 1998) (“Vicisano”).

Chiu US 6,505,253 B1 Jan. 7, 2003
(filed June 18, 1999)

REJECTION AT ISSUE
Claims 1-12 are rejected under 35 U.S.C. § 103(a) as being
unpatentable over Vicisano in view of Chiu. Ans. 4-9.

Appeal 2009-011058
Application 09/587,542

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ISSUE
Appellant argues on pages 8-10 of the Appeal Brief and pages 2-3 of
the Reply Brief that the Examiner’s rejection of claims 1-12 is in error.
These arguments present the following issue: Did the Examiner err in
finding that Vicisano in view of Chiu discloses reducing the sending rate of
layers over time independent of receiver feedback?1
ANALYSIS
Claim 1 requires the sending rate of at least one of the layers to be
reduced independent of receiver feedback. Independent claims 3 and 8
contain similar limitations. Claims 2, 4-7, and 9-12 depend upon claims 1,
3, or 8. The Examiner finds that Chiu discloses a system wherein bits are
transmitted for a particular period of time (a window), not transmitted for a
period of time, transmitted for a period of time, etc., indicating that the
transmission rate is reduced or increased as time passes. Additionally, the
Examiner finds that Chiu’s system operates in an “insensitive” mode,
wherein the transmission rate is adjusted independent of receiver feedback.
Thus, the Examiner finds that Chiu reduces the transmission rate over time
independent of receiver feedback. Ans. 10. We disagree.
We agree with Appellant that the Examiner is misinterpreting the
reference and that Chiu does not disclose reducing the transmission rate
when operating in the insensitive mode. Reply Br. 3. While feedback from
the receivers is not used in Chiu’s insensitive mode (col. 24, ll. 33-35), we
do not find any evidence to support the Examiner’s conclusion that

1 Appellant makes additional arguments with respect to claims 1, 3 and 8.
App. Br. 9. However, we do not reach these additional issues since this
issue is dispositive of the case.
Appeal 2009-011058
Application 09/587,542

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transmission rates are reduced when the system is operating in this mode, as
required by the independent claims. Thus, we cannot sustain the Examiner’s
rejection of claims 1-12.
CONCLUSION
The Examiner erred in finding that Vicisano in view of Chiu discloses
reducing the sending rate of layers over time independent of receiver
feedback.
SUMMARY
The Examiner’s decision to reject claims 1-12 is reversed.

REVERSED

msc