Ex Parte AnsariDownload PDFPatent Trial and Appeal BoardDec 18, 201411616988 (P.T.A.B. Dec. 18, 2014) Copy Citation 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. 11/616,988 12/28/2006 Furquan Ahmed Ansari Ansari 6 (LCNT/128194) 3475 46363 7590 12/18/2014 WALL & TONG, LLP/ ALCATEL-LUCENT USA INC. 25 James Way Eatontown, NJ 07724 EXAMINER PREVAL, LIONEL ART UNIT PAPER NUMBER 2475 MAIL DATE DELIVERY MODE 12/18/2014 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 FURQUAN AHMED ANSARI ______________ Appeal 2012-007186 Application 11/616,988 Technology Center 2400 ______________ Before JEFFREY S. SMITH, JOHNNY A. KUMAR, and MICHAEL J. STRAUSS, Administrative Patent Judges. KUMAR, Administrative Patent Judge. DECISION ON APPEAL This is a decision on appeal under 35 U.S.C. § 134(a) from the Examiner’s non-final rejection of claims 1–10, 12–14, 17, 18, 20–23, and 25. Claim 11, 15, 16, 19, and 24 are cancelled. We have jurisdiction under 35 U.S.C. § 6(b). We affirm. Appeal 2012-007186 Application 11/616,988 2 STATEMENT OF THE CASE Appellant’s invention generally relates to a method for controlling fragmentation of packets transmitted from a sending device toward a receiving device. A packet of the sending device is received at a router. The packet has a packet size associated therewith. An expect path for the packet is determined at the router. The expected path comprises a plurality of links. A minimum Media Transmission Unit (MTU) size of the expected path is determined at the router. The MTU size of the expected path is determined using a respective plurality of MTU sizes of the links of the expected path. In response to a determination that the packet size is greater than the minimum MTU size of the expected path, a message is propagated from the router toward the sending device. The message is configured to cause the sending device to constrain packet sizes of subsequent packets transmitted by the sending device to be less than or equal to the minimum MTU size of the expected path. See Abstract and Fig. 1. Packet fragmentation and reassembly are avoided because the packets received from the sending device have packet sizes that are less than or equal to the MTU size associated with that path in the network. Spec. 7, ll. 13–19. Exemplary claims 1, 12, and 25 recite: 1. A method for controlling fragmentation of packets transmitted from a sending device toward a receiving device, comprising: receiving, at a router, a packet of the sending device, the packet having a packet size associated therewith; determining, at the router, an expected path for the packet, wherein the expected path comprises a plurality of links; Appeal 2012-007186 Application 11/616,988 3 determining, at the router, a minimum Media Transmission Unit (MTU) size of the expected path using a respective plurality of MTU sizes of the links of the expected path; and in response to a determination that the packet size is greater than the minimum MTU size of the expected path, propagating, from the router toward the sending device, a message for causing the sending device to constrain packet sizes of subsequent packets transmitted by the sending device to be less than or equal to the minimum MTU size of the expected path. 12. A method, comprising: generating, at a router, a link state advertisement (LSA) for a link associated with the router, wherein the LSA comprises a link Type-Length-Value (TLV), wherein the link TLV comprises a sub-TLV including MTU information associated with the link; and propagating the LSA toward at least one other router. 25. An apparatus for maintaining a Media Transmission Unit (MTU) size table, the apparatus comprising: a processor configured for: receiving, at a router, a status message associated with a link, wherein the status message comprises an MTU size of the link; identifying, in the MTU size table, a table entry associated with the link; and updating the identified table entry of the MTU size table to include the MTU size of the link. Appeal 2012-007186 Application 11/616,988 4 Rejections Claims 1, 3–5, 10, 22, and 25 stand rejected under 35 U.S.C. § 102(a) as being unpatentable over Pancholi (US 2006/0045131 A1, Mar. 2, 2006). Ans. 4–8. Claims 2, 6–8, and 18 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Pancholi and Mirtorabi (US 2007/0214275 A1, Sept. 13, 2007). Ans. 8–12. Claim 9 stands rejected under 35 U.S.C. § 103(a) as being unpatentable over Pancholi, Mirtorabi, and Katz (D. Katz et al., Traffic Engineering (TE) Extensions to OSPF Version 2, IETF RFC 3630 (Sept. 2003)). Ans. 12. Claims 12 and 13 stand rejected under 35 U.S.C. § 102(e) as being unpatentable over Mirtorabi. Ans. 13–14. Claim 14, 17, 20, 21, and 23 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Mirtorabi and Pancholi. Ans. 14–18. ANALYSIS Rather than reiterate the arguments of Appellant and the Examiner, we refer to the Appeal Brief (“App. Br.”) filed October 11, 2011, the Answer (“Ans.”) mailed February 22, 2012, and the Reply Brief (“Reply Br.”) filed March 27, 2012, for the respective details. We have considered in this decision only those arguments Appellant actually raised in the Briefs. Any other arguments that Appellant could have made but chose not to make in the Briefs are deemed to be waived. See 37 C.F.R. § 41.37(c)(1)(vii). The Examiner has provided a comprehensive response to each argument presented by the Appellant on pages 18 through 22 of the Answer. We have reviewed this response and concur with the Examiner’s findings Appeal 2012-007186 Application 11/616,988 5 and conclusions. We adopt as our own (1) the findings and reasons set forth by the Examiner in the action from which this appeal is taken and (2) the reasons set forth by the Examiner in the Examiner’s Answer in response to Appellant’s Appeal Brief. Ans. 4–22. We highlight and address specific findings and arguments for emphasis as follows. Section 102 rejection of claims 1, 3–5, 10, and 22 over Pancholi Based on Appellant’s arguments in the Appeal Brief (App. Br. 12– 14), the principal and dispositive issue of whether the Examiner erred in rejecting claims 1, 3–5, 10, and 22 turns on whether Pancholi discloses, determining, at the router, a minimum Media Transmission Unit (MTU) size of the expected path using a respective plurality of MTU sizes of the links of the expected path; and in response to a determination that the packet size is greater than the minimum MTU size of the expected path, propagating, from the router toward the sending device, a message for causing the sending device to constrain packet sizes of subsequent packets transmitted by the sending device to be less than or equal to the minimum MTU size of the expected path. Claim 1 (emphasis ours). Appellant contends, “Pancholi merely mentions a server, and does not teach or suggest determining a minimum MTU size for an expected path at a router” (Reply Br. 2), and “Pancholi merely mentions a server, and does not teach or suggest propagating a message from a router.” Reply Br. 3. The Examiner finds that in Pancholi the PMTU server 104 corresponds to the claimed router. Ans. 5–6 (citing Pancholi, Fig. 1). We concur with the Examiner’s finding because server 104 performs the functions of a router. Ans. 5, 18–20. Appeal 2012-007186 Application 11/616,988 6 Appellant admits that Pancholi “defines the PMTU” but contends that Pancholi “does not provide any teaching or suggestion as to how the PMTU is determined.” Reply Br. 2. The Examiner finds, and we agree, Pancholi discloses this feature: Every network link has a maximum packet size called the link’s Maximum Transmission Unit (MTU). The full path from one computer to another may travel across many links with different MTUs. The minimum of the MTUs for all of the links in a path is the PMTU. Ans. 18 (quoting Pancholi ¶ 8). Regarding Appellant’s contention that Pancholi does not disclose “propagating a message” or a “condition which causes the PMTU reply 134 to be sent” (App. Br. 13–14), we adopt as our own the Examiner’s findings of fact and reasons set forth in the Examiner’s Answer (Ans. 18–21) and concur with the Examiner’s conclusions. It follows that Appellant has not shown error in the Examiner’s rejection of claims 1, 3–5, 10, and 22. Further, because Appellant has not presented any persuasive arguments challenging the Examiner’s rejection of claims 6, 8–10, 13, and 14, we likewise affirm these claims for the reasons set forth for claim 1. Section 102 rejection of claim 25 over Pancholi Regarding claim 25, while Appellant raised additional arguments for patentability (App. Br. 15–19), we find that the Examiner has rebutted in the Answer each and every one of those arguments supported by sufficient evidence. Ans. 21. Therefore, we adopt the Examiner’s findings and underlying reasoning, which are incorporated herein by reference. In the Reply Brief, Appellant responds that Pancholi is “devoid of any teaching or suggestion that the PMTU update 152 is received at a router.” Appeal 2012-007186 Application 11/616,988 7 Reply Br. 6. For the reasons discussed supra with respect to the rejection of claim 1, we find Pancholi discloses the claimed router. Because Appellant has not shown reversible error in the Examiner’s findings, we affirm the Examiner’s rejection of claim 25 as anticipated by Pancholi. Section 102 rejection of claims 12 and 13 over Mirtorabi Based on Appellant’s arguments in the Appeal Brief (App. Br. 19– 20), the principal and dispositive issue of whether the Examiner erred in rejecting claims 12 and 13 turns on whether Mirtorabi discloses “wherein the link TLV comprises a sub-TLV including MTU information associated with the link,” (emphasis ours) as recited in independent claim 12. Appellant contends, “The AS numbers of the AS-path sub-TLV as disclosed in Mirtorabi do not teach or suggest MTU information associated with a link as claimed in Appellant’s claim 12.” Reply Br. 7. The Examiner finds Mirtorabi discloses: OSPF employs conventional link-state advertisements (LSA) for exchanging routing and topology information between a set of interconnected intermediate network nodes, i.e., routers and switches. In fact, different types of LSAs may be used to communicate the routing and topology information. Mirtorabi ¶ 11 (emphasis ours); Ans. 11. Thus, we find the claimed “MTU information” encompasses Mirtorabi’s routing and topology information. It follows that Appellant has not shown error in the Examiner’s rejection of claims 12 and 13. Appeal 2012-007186 Application 11/616,988 8 Section 103 rejections of claims 2, 6-9, 14, 17, 18, 20, 21, and 231 Appellant provided additional arguments with respect to the patentability of claims 17, 18, 20, 21, and 23 (App. Br. 20–23). The Examiner has rebutted each of those arguments in the Answer by a preponderance of the evidence (Ans. 6–18). Therefore, we agree with the Examiner’s findings and underlying reasoning and adopt them as our own. Consequently, we conclude there is no reversible error in the Examiner’s rejections of claims 2, 6–9, 14, 17, 18, 20, 21, and 23. DECISION The Examiner’s rejections of claims 1–10, 12–14, 17, 18, 20–23, and 25 are 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 msc 1 Appellant allows dependent claims 2 and 6–9 to stand or fall with independent claim 1, and claim14 to stand or fall with claim 12. App. Br. 20, 22. Copy with citationCopy as parenthetical citation