Ex Parte Grosse et al

Patent Trial and Appeal Board

Oct 30, 2013

11592725 (P.T.A.B. Oct. 30, 2013)

UNITED STATES PATENT AND TRADEMARKOFFICE
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.
11/592,725 11/03/2006 Eric H. Grosse 18-19 9807
7590 10/31/2013
Ryan, Mason & Lewis, LLP
Suite 205
1300 Post Road
Fairfield, CT 06824
EXAMINER
LEWIS, LISA C
ART UNIT PAPER NUMBER
2495
MAIL DATE DELIVERY MODE
10/31/2013 PAPER
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.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
____________________

Ex parte ERIC H. GROSSE and CLIFFORD E. MARTIN
____________________

Appeal 2011-0028871
Application 11/592,725
Technology Center 2400
____________________

Before JEAN R. HOMERE, BRYAN F. MOORE and
JOHN A. EVANS, Administrative Patent Judges.

HOMERE, Administrative Patent Judge.

DECISION ON APPEAL

1 The real party in interest is Lucent Technologies Inc. (App. Br. 1.)

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Application 11/592,725

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STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Examiner’s final
rejection of claims 1-20. (App. Br. 1.) We have jurisdiction under 35
U.S.C. § 6(b).
We affirm.
Appellants’ Invention
Appellants invented a method and system for protecting a target
computer within an enterprise network (150) against unwanted traffic
originating from outside computing devices (110). (Fig. 1, Spec. 2, ll. 19-
24.) In particular, upon receiving an incoming packet from an outside
computing device (110), a central filter (200) at a service provider network
(120) identifies the source address (IP address) of the computing device, and
forwards the identified IP address to an override filter (140), which converts
the IP address into a corresponding domain name address. If the converted
domain name address satisfies a regular expression in the override filter
listing, the received packet is transmitted to the target computing device.
(Spec. 4, ll. 11-26.)
Illustrative Claim
Independent claim 1 further illustrates the invention as follows:

1. A method for defending against unwanted traffic received by a
target victim, the target victim having one or more destination
addresses, the method comprising the steps of:
maintaining a central filter identifying a source address of at
least one source computing device whose transmission of packets to
said target victim is to be one or more of limited, dropped or allowed;
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maintaining an override filter listing at least one regular
expression identifying one or more source computing devices whose
transmission of packets to said target victim should be transmitted to
said target victim regardless of an entry in said central filter;
converting said source address to a domain name address in a
Domain Name Service format if said central filter indicates that at
least one received packet is received from said at least one source
computing device; and
transmitting said at least one received packet to said target
victim if said converted domain name address in said Domain Name
Service format satisfies a regular expression appearing in said
override filter.
Prior Art Relied Upon
The Examiner relies on the following prior art as evidence of
unpatentability:
Bellovin U.S. 2006/0070122 A1 Mar. 30, 2006
Carpenter U.S. 2006/0075496 A1 Apr. 6, 2006
Byrnes U.S. 2008/0052758 A1 Feb. 28, 2008
Klein WO 2006/090392 A2 Aug. 31, 2006
Quinn, Session Description Protocol (SDP) Source Filters, IETF
Standard, Internet Engineering Task Force, July 2006

Rejections on Appeal
The Examiner rejects claims 1-20 as follows:
1. Claims 1, 3-6, 9, 10, 12-15, 18, and 19 stand rejected under 35 U.S.C.
§ 103(a) as being unpatentable over the combination of Byrnes and
Klein.
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2. Claims 2 and 11 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over the combination of Byrnes, Klein, and Carpenter.
3. Claims 7, 16, and 20 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over the combination of Byrnes, Klein, and Quinn.
4. Claims 8 and 17 stand rejected under 35 U.S.C. § 103(a) as being
unpatentable over the combination of Byrnes, Klein, and Bellovin.

ANALYSIS
We consider Appellants’ arguments seriatim as they are presented in
the Appeal Brief, pages 4-8 and the Reply Brief, pages 2-7.

Dispositive Issue: Under 35 U.S.C. § 103(a), did the Examiner err in
finding that the combination of Byrnes and Klein teaches or suggests
converting a source address to a domain name address, as recited claim 1?
Appellants argue that the proposed combination of Byrnes and Klein
does not teach or suggest the disputed limitations emphasized above. (App.
Br. 4-6, Reply Br. 2-5.) According to Appellants, because Byrnes discloses
a whitelist containing both a list of IP addresses and domains from which a
user can simply look up a source address or a domain name address, Byrnes
does not teach a reverse DNS look up or converting the source address to a
domain name address. (Id.) In response, the Examiner finds that even
though the disclosed whitelist (override filter) includes both IP addresses
and domains, the association therebetween is not readily ascertainable.
Consequently, Klein’s disclosure of a reverse DNS lookup would allow
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users of Byrnes’ system to determine how IP addresses are related to the
domains in the whitelist. (Ans. 9-10.)
On the record before us, we agree with the Examiner’s conclusion of
obviousness. We note, at the outset, Appellants do not dispute that DNS
reverse look up is well-known in the art, as evidenced by Klein. Therefore,
the main issue turns on whether such a well-known technique would
complement Byrnes’ teaching to yield the disputed limitations. We answer
this inquiry in the affirmative. In particular, because the conversion of IP
addresses to corresponding domains is nothing other than looking up domain
names in a repository based upon an IP address associated therewith, we find
that only routine skill would be required for the artisan to look up domain
names in the whitelist based upon a received IP address. Consequently, we
agree with the Examiner that Byrnes and Klein disclose prior art elements
that perform their ordinary functions to predictably result in a system for
looking up domain names based on entered IP addresses and vice-versa.
Therefore, we do not agree with Appellants that Klein’s reverse lookup
teaches away from Byrnes’ disclosure of storing the domains and IP address
in the whitelist. It follows Appellants have not shown error in the
Examiner’s rejection of claim 1.
Regarding the rejection of claim 7, Appellants argue that the
combination of Byrnes, Klein, and Quinn does not teach or suggest using a
DNS mask containing a wild card field, wherein the DNS is a regular
expression listed in an override filter. (App. Br. 7, Reply Br. 7-8.) This
argument is not persuasive. We agree with the Examiner’s finding that
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Quinn’s disclosure of including a wild card in a DNS mask would
complement the Byrnes-Klein system to predictably result in an override
filter including a DNS mask containing a wild card, which in response to
receiving a regular expression, produces a requested IP address and/or
related domains. (Ans. 10.) It follows, therefore, that Appellants have not
shown error in the Examiner’s rejection of claim 7.
Regarding the rejections of claims 1, 9, 16, 19 and 20, Appellants
substantially reiterate the same arguments previously submitted for
patentability of claims 1 and 7 above. As per the foregoing discussions,
these arguments are not persuasive. See 37 C.F.R. § 41.37(c)(1)(vii).
Regarding claims 2-6, 8, 10-15, 17, and 18, Appellants have provided
no rebuttal arguments. Any argument that Appellants could have submitted
are therefore waived.
DECISION
We affirm the Examiner’s rejections of claims 1-20 as set forth above.
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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