Ex Parte Sollee

Board of Patent Appeals and Interferences

Jul 31, 2007

09881594 (B.P.A.I. Jul. 31, 2007)

The opinion in support of the decision being entered today
is not binding precedent of the Board

UNITED STATES PATENT AND TRADEMARK OFFICE
____________________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________________

Ex parte PATRICK N. SOLLEE
____________________

Appeal 2007-1063
Application 09/881,5941
Technology Center 2100
____________________

July 31, 2007
____________________

Before: ALLEN R. MacDONALD, JEAN R. HOMERE, and MARC S.
HOFF, Administrative Patent Judges.

HOFF, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF CASE
Appellant appeals under 35 U.S.C. § 134 from a final rejection of
claims 1-6, 25, 26, 30, 31, 33-36, 38 and 392. We have jurisdiction under 35
U.S.C. § 6(b).

1 Application filed June 14, 2001. The real party in interest is Nortel
Networks Limited.
Appeal 2007-1063
Application 09/881,594

We affirm.
Appellant’s invention relates to communication between a device
protected by a firewall and network address translator (NAT), and another
device located on the outside of the firewall and NAT. Because the firewall
rejects unsolicited communications from outside devices, the invention
contemplates that communication originates from the device protected by
the firewall. A communications path is set up through the firewall, and so-
called “keep-alive” messages are transmitted to maintain that
communications path.

Claim 1 is exemplary:
1. A method for use in communications involving a first
terminal that is coupled to one side of a firewall and network address
translator, the method comprising:

sending, by the first terminal, a message identifying the first
terminal to a node on another side of the firewall and network address
translator;

receiving, by the first terminal, another message from the node,
wherein the messages between the first terminal and the node causes
creation of a path through the firewall and network address translator;
and

repeatedly sending keep-alive messages to maintain the path
through the firewall and network address translator.

2 Claims 7, 32 and 37 were canceled in the Reply Brief filed October 10,
2006.
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The prior art relied upon by the Examiner in rejecting the claims on
appeal is:
Thomas US 2002/0184316 A1 Dec. 5, 2002
Roach US 2002/0037723 A1 Mar. 28, 2002

Claims 1-4, 25, 26, 30, 31, 33-36, 38 and 39 stand rejected under 35
U.S.C. § 102(e) as being anticipated by Thomas. Claims 5 and 6 stand
rejected under 35 U.S.C. § 103(a) as being obvious over Thomas in view of
Roach.
Appellant contends that the Examiner erred in that Thomas does not
anticipate nor render obvious the claimed invention, because Thomas
teaches repeatedly initiating communication, rather than maintaining an
existing communication path. The Examiner argues that Thomas may fairly
be read to meet the claims, because while Thomas may use different
terminology, his invention performs the same functions claimed by
Appellant.
Rather than repeat the arguments of Appellant or the Examiner, we
make reference to the Briefs and the Answer for their respective details.
Only those arguments actually made by Appellant have been considered in
this decision. Arguments that Appellant could have made but chose not to
make in the Briefs have not been considered and are deemed to be waived.
See 37 C.F.R. § 41.37(c)(1)(vii) (2004).3

3 Appellant has not presented any substantive arguments directed separately
to the patentability of the dependent claims or related claims in each group,
except as will be noted in this opinion. In the absence of a separate
argument with respect to those claims, they stand or fall with the
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ISSUE
The principal issue in the appeal before us is whether the Appellant
has shown that the Examiner erred in holding that the repeated initiation of
communication from a client behind a firewall to a server on the other side
of the firewall may fairly be interpreted to equate to the maintenance of a
communications path between the two devices.

FINDINGS OF FACT
The following Findings of Fact (FF) are shown by a preponderance of
the evidence.
The Invention
1. Appellant invented a method of communicating with a device
coupled to one side of a firewall and network address translator (NAT)
(Specification 3:2-4).
2. Because a firewall rejects unsolicited communications from
devices outside the firewall, the method contemplates that the first device,
located behind the firewall, shall initiate communication with a node on the
other side of the firewall. Upon receipt of a response from the node, a
communications “path” through the firewall and NAT is created
(Specification 7:24 – 8:2).
3. The communications path through the firewall and NAT is
maintained by repeatedly sending keep-alive messages, such that the
network address translation information regarding the first device and the
representative independent claim. See In re Young, 927 F.2d 588, 590, 18
USPQ2d 1089, 1091 (Fed. Cir. 1991). See also 37 C.F.R. § 41.37(c)(1)(vii).

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node is retained and not deleted. In one embodiment of the invention, the
first device, residing behind the firewall, sends the keep-alive messages
through the firewall and NAT to the node (Specification 8:2-5).
Thomas
4. Thomas teaches repeated back-and-forth communication
between a client located on one side of a firewall and NAT, and a server
located on the other side (Para. [0014]).
5. Thomas teaches that, because a firewall rejects unsolicited
communication from devices located outside, the client device is designated
to initiate communication with the server (Para. [0014]).
6. Thomas teaches that the client sends an identifying message to
a node on the other side of the firewall / NAT; receiving a response from the
node, wherein the messages from the client and node cause creation of a
path through the firewall / NAT; and conducting repeated further
communication between the client behind the firewall and the node on the
other side of the firewall (Para. [0038]).
7. Thomas further teaches that if a communications session is
initiated by the MAPI client, a MAPI server will use the IP address in the
packet header to communicate with that MAPI client for the duration of that
session (Para. [0038]).
8. In Thomas, a communications session between the MAPI client
and the MAPI server can be initiated by the MAPI client at a periodic
interval, for example every thirty seconds, every minute, five minutes, ten
minutes, or other appropriate period for that MAPI client and network (Para.
[0039]).
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9. Thomas suggests that an interval of thirty seconds or longer
“appears to strike an appropriate balance between MAPI client and network
bandwidth usage and apparent responsiveness of the MAPI client to the
user” (Para. [0039]).
10. In Thomas, the user can enable or disable the communication
initiator functionality by clicking on the check-box 34 that is labeled
“Enable Firewall Keep-Alive.” If the check-box 34 is selected, the
communication initiator functionality is enabled, and the user can set the
time period 39 for periodically repeated communications session initiation.
The user may select a shorter or longer interval at which the client initiates
communication with the server, for example 30 seconds, one minute, five
minutes, etc. (Para. [0051]).
11. Thomas does not disclose an upper or lower limit on the size of
the communication interval.
Roach
12. Roach teaches a registration message comprising a Session
Initiation Protocol (SIP) REGISTER message (Para. [0102]-[0105]).
13. Roach teaches that the SIP REGISTER request informs a proxy
that a party is at a specific host on a network. The address bindings
registered through SIP are periodically refreshed, and are eventually
removed (Para. [0010]).

PRINCIPLES OF LAW
Anticipation is established when a single prior art reference discloses
expressly or under the principles of inherency each and every limitation of
the claimed invention. Atlas Powder Co. v. IRECO Inc., 190 F.3d 1342,
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1347, 51 USPQ2d 1943, 1946 (Fed. Cir. 1999); In re Paulsen, 30 F.3d 1475,
1478-79, 31 USPQ2d 1671, 1673 (Fed. Cir. 1994).
In rejecting claims under 35 U.S.C. § 103, the Examiner bears the
initial burden of establishing a prima facie case of obviousness. In re
Piasecki, 745 F.2d 1468, 1472, 223 USPQ 785, 788 (Fed. Cir. 1984). The
Examiner can satisfy this burden by showing some articulated reasoning
with some rational underpinning to support the legal conclusion of
obviousness. KSR Int’l. v. Teleflex Inc., 127 S. Ct. 1727, 1741, 82 USPQ2d
1385, 1396 (2007) (citing In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329,
1336 (Fed. Cir. 2006)). Only if this initial burden is met does the burden of
coming forward with evidence or argument shift to the Appellant. Piasecki,
745 F.2d at 1472, 223 USPQ at 788. Thus, the Examiner must not only
assure that the requisite findings are made, based on evidence of record, but
must also explain the reasoning by which the findings are deemed to support
the Examiner’s conclusion.

ANALYSIS
Rejection under 35 U.S.C. § 102(e)
Appellant asserts that Thomas fails to anticipate Appellant’s claimed
invention, because Thomas does not teach “repeatedly sending keep-alive
messages to maintain the path through the firewall and network address
translator.” Appellant asserts that because the ordinary meaning of
“maintain” is “to keep in an existing state” (Br. 4:10, citing Merriam-
Webster Online Dictionary), Thomas cannot anticipate the claimed
invention, because Thomas teaches repeatedly initiating communication
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sessions between a Messaging Application Programming Interface (MAPI)
client, located behind a firewall and NAT, and a MAPI server (Br. 4:13-15).
Like Appellant’s invention, Thomas teaches a system and method for
communication with a client located behind a firewall and network address
translator (FF 4). Thomas teaches that the client sends an identifying
message to a node on the other side of the firewall / NAT; receiving a
response from the node, wherein the messages from the client and node
cause creation of a path through the firewall / NAT; and conducting repeated
further communication between the client behind the firewall and the node
on the other side of the firewall (FF 6).
Because Thomas teaches communication between a client behind a
firewall and NAT, and a node on the other side of the devices (FF 4),
Thomas necessarily uses similar address translation methods, because of the
presence of the known NAT (see FF 7). Thomas further teaches that this
communication may be repeatedly “initiated” by invoking a function known
as “Firewall Keep-Alive” (FF 10). In the system of Thomas, the user may
select the desired interval between initiation of communication sessions (FF
8). “Initiation” of communication at sufficiently short intervals, i.e. shorter
than the time-out in the NAT after which address translation information is
deleted, results in a device in which communication is “maintained” just as
Appellant argues. Subsequent communication “initiation” from the client
would occur before the address information in the NAT expired (see FF 7),
and thus the communications path through the firewall would never be
dropped. Appellant has presented no evidence that the thirty second interval
between sessions disclosed in Thomas (FF 10) is insufficient to “maintain”
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the communications path through the firewall. As a result, Appellant has
failed to carry his burden of establishing that the Examiner erred in
interpreting the reference. We find that Thomas discloses all the limitations
of the invention claimed in representative claims 1 and 25, and that the
Examiner did not err in his rejection of claims 1-4, 25 and 26 under 35
U.S.C. § 102.
With regard to claims 30 and 35, Appellant argues that Thomas does
not teach repeatedly sending the keep-alive messages to maintain the path
through the firewall and network address translator … for a duration of the
registration of the first terminal” (Br. 7:7-9). We disagree, for the reasons
held supra. Thomas may fairly be interpreted to teach that one may select an
interval between communication sessions short enough that the path between
client and server would never be dropped. The “initiation” messages then
become the equivalent of “keep-alive” messages, which would be sent for
the [indefinite] duration of the registration of the first terminal. We therefore
find no error in the Examiner’s rejection of claims 30 and 35 under 35
U.S.C. § 102.
With regard to claims 33, 34, 38 and 39, Appellant argues that
Thomas does not teach “causing a mapping table to be maintained by the
firewall and network address translator” (Br. 8:16-17), because as noted
supra, the repeated initiation of communication taught by Thomas does not
correspond to the maintenance claimed by Appellant. For the reasons held
above, we read Thomas to anticipate these claims as well. Thomas teaches
that if a communications session is initiated by the MAPI client, a MAPI
server will use the IP address in the packet header to communicate with that
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MAPI client for the duration of that session (FF 7). Thomas may fairly be
interpreted to teach that one may select an interval between communication
sessions short enough that the path between client and server would never be
dropped. We therefore find that the Examiner did not err in rejecting claims
33, 34, 38 and 39 under 35 U.S.C. § 102.
Rejection under 35 U.S.C. § 103(a)
With regard to claims 5 and 6, Appellant argues that the Examiner has
not provided any objective evidence to support his conclusion that it would
have been obvious to modify Thomas to include sending a Session Initiation
Protocol (SIP) REGISTER message as taught by Roach (Br. 9:18-20).
Appellant further states that “Thomas relates to the initiation of
communications sessions by a MAPI client with a MAPI server to enable the
MAPI client to receive electronic mail, calendar items, and task items from
the MAPI server” (Br. 9:20-22), and that “substituting the SIP messages into
the system of Thomas would likely render Thomas inoperable for its
intended purpose, since SIP generally is used for establishing … telephony
voice call sessions or multimedia call sessions” (Br. 10:10-13). We do not
agree that Thomas’s intended purpose is so limited. Thomas discloses that
“[i]n an embodiment of the invention, an extension to a client software
application is provided that can enable use of the client with a server across
a network that includes such a firewall or gateway” (FF 4; para. [0014]).
One of Thomas’s embodiments does involve electronic mail, but Thomas is
careful to state that the examples recited (electronic mail messages, calendar
items, task items) are “without limitation” (para. [0018]). The Examiner
stated that the skilled artisan “would have been motivated to [modify
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Thomas in view of Roach] to initiate real time media data sessions” (Answer
7:18-20). Because Thomas is not limited to electronic mail communications,
and contains no teaching excluding telephonic or multimedia
communication, we find that the Examiner did not err in rejecting claims 5
and 6 under 35 U.S.C. § 103(a).
Other Issues
Should there be further prosecution of this application, we bring the
following references to the attention of Appellant and the Examiner:
Dingman US 2004/0024879 A1 Feb. 5, 2004
Oren US 2003/0145093 A1 Jul. 31, 2003
Stephenson US 2002/0023143 A1 Feb. 21, 2002

Dingman teaches transmitting a message, e.g., every 30 seconds to
keep the path in the firewall/NAT open in case a user agent is behind a
NAT/firewall (para. [0115]). Oren teaches maintaining a connection by
having a client module send a keep-alive message every few hundred
seconds (para. [0062]). Stephenson teaches sending a keep-alive message to
maintain a connection through a firewall (para. [0108]).
Although Dingman is not prior art to Appellant, the reference can be
used as evidence to confirm what the Thomas patent would teach to one of
ordinary skill in the art.

CONCLUSION OF LAW
We conclude that Appellant has not shown that the Examiner erred in
rejecting claims 1-6, 25, 26, 30, 31, 33-36, 38 and 39. Claims 1-6, 25, 26,
30, 31, 33-36, 38 and 39 are not patentable.

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DECISION
The Examiner’s rejection of claims 1-6, 25, 26, 30, 31, 33-36, 38 and
39 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

gw

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