Ex Parte Dahan et al

Patent Trial and Appeal BoardNov 21, 2012

10322893 (P.T.A.B. Nov. 21, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE ____________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ____________________ Ex parte FRANCK B. DAHAN and BERTRAND CORNILLAULT ____________________ Appeal 2010-004003 Application 10/322,893 Technology Center 2400 ____________________ Before DEBRA K. STEPHENS, KALYAN K. DESHPANDE, and JUSTIN BUSCH, Administrative Patent Judges. BUSCH, Administrative Patent Judge. DECISION ON APPEAL Appeal 2010-004003 Application 11/322,893 2 Appellants appeal under 35 U.S.C. § 134(a) from the Examiner’s final rejection of claims 3-11 and 13-19. We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM. Introduction According to Appellants, the invention “relates to microprocessors, and more specifically to improvements in security mechanisms to support secure software services.” Spec. ¶ 2. STATEMENT OF THE CASE Exemplary Claim Claim 5 is an exemplary claim and is reproduced below: 5. A method of operating a digital system including a graphics display and secure computing resources, comprising the steps of: in a non-secure mode, preventing access to the secure computing resources; executing an application program; displaying results of the executing step on the graphics display; entering into a secure mode of operation for executing a secure portion of the application program by: jumping to an entry address at a particular address in an instruction memory; executing an activation sequence of instructions beginning at the entry address; and entering the secure mode of operation only if the activation sequence of instructions is fully executed by the CPU in a pre-defined order; Appeal 2010-004003 Application 11/322,893 3 then unlocking access to the secure computing resources; and executing the secure portion of the application program using the secure computing resources, including activating a secure mode indicator that is independent from the graphics display; wherein the secure mode indicator can only be activated by the trusted program code while in the secure mode of operation. References Veil 6,092,202 Jul. 18, 2000 Boebert 5,822,435 Oct. 13, 1998 Takahashi 5,615,263 Mar. 25, 1997 Flyntz 6,389,542 B1 May 14, 2002 Hobson 5,745,676 Apr. 28, 1998 Gurak 4,368,357 Jan. 11, 1983 Schuster 6,914,897 B1 Jul. 5, 2005 Rejections Claims 3, 5, 6, 9, 10, 11, 17, and 18 stand rejected under 35 U.S.C. § 103(a) as being obvious in view of Boebert, Veil, and Takahashi. Claims 4, 13, and 14 stand rejected under 35 U.S.C. § 103(a) as being obvious in view of Boebert, Veil, Takahashi, and Flyntz. Claims 7 and 8 stand rejected under 35 U.S.C. § 103(a) as being obvious in view of Boebert, Veil, Takahashi, and Hobson. Claims 15 and 16 stand rejected under 35 U.S.C. § 103(a) as being obvious in view of Boebert, Veil, Takahashi, Flyntz, and Gurak. Appeal 2010-004003 Application 11/322,893 4 Claim 19 stands rejected under 35 U.S.C. § 103(a) as being obvious in view of Boebert, Veil, Takahashi, and Schuster. ISSUE 35 U.S.C. § 103(a) (Boebert, Veil, and Takahashi): claims 5 and 171 Appellants argue their invention is not rendered obvious by the combination of Boebert, Veil, and Takahashi, alone or in combination with additional references. App. Br. 11-34. Specifically, Appellants argue that Takahashi “fails to teach the claimed steps of executing an activation sequence and of entering the secure mode of operation.” App. Br. 11-17, 27- 31. Appellants also argue that combining Takahashi with the combined Boebert-Veil system would render that system inoperable. App. Br. 17-21. Issue 1a: Has the Examiner erred in finding that Takahashi, in combination with Boebert and Veil, teaches or suggests “executing an activation sequence of instructions beginning at the entry address” and “entering the secure mode of operation only if the activation sequence of instructions is fully executed by the CPU in a pre-defined order,” as recited in claim 5? Issue 1b: Has the Examiner erred in combining Takahashi with Boebert and Veil? 1 Claim 17 is a system claim that includes similar limitations to those limitations at issue in method claim 5. We have reviewed Appellants’ arguments with respect to claim 17 (and its dependent claims) and apply the same analysis to reach the same conclusion as with respect to claim 5. Appeal 2010-004003 Application 11/322,893 5 ANALYSIS Appellants argue that the Examiner ignores the claim term “pre- defined order” and that the plain meaning of “pre-defined order” as used in the claims requires executing the activation sequence instructions in a particular order. Reply Br. 6. Appellants then assert that the “pre-defined order” in each claim on appeal “defines a test against which the actual activation sequence is compared to determine whether the secure mode ought to be entered.” Id. Appellants further argue that the Examiner’s application of Takahashi conflates a “pre-defined order” with a “pre-defined result.” Reply Br. 7. In support of this argument, Appellants argue that the Examiner’s interpretation of Takahashi’s teachings would allow unauthorized entry into secure mode because “nothing in the Takahashi reference determines whether the order of execution of the interrupt handler instructions is the same as that originally programmed, and nothing … suggests aborting secure mode entry if that original order is not followed.” Reply Br. 7-8. We agree with Appellants that “pre-defined order” requires execution of instructions in a particular order. However, we disagree with Appellants that the Examiner ignores the claim term “pre-defined order.” In fact, the Examiner addressed the “pre-defined order” throughout the Answer. Ans. 3- 4, 11-13. For example, the Examiner found that “all instructions in a routine must be processed in a certain order and fully execute these instructions for the interrupt to be correctly handled before the secured mode is entered.” Ans. 3. We find that the broadest reasonable interpretation, in light of the Appeal 2010-004003 Application 11/322,893 6 Specification, of “pre-defined order” includes a particular order of executing instructions that is determined prior to execution, which is consistent with the Examiner’s rejections. See, e.g., Ans. 3, 11.Appellants are arguing limitations (“the order of execution of the … instructions is the same as that originally programmed”) not recited in the claims. Reply Br. 8. As the Examiner explained, and contrary to Appellants’ position (App. Br. 15-16), the claims as presented do not require that “something other than the full execution of an activation sequence of instructions in that pre-defined order exists, and would not cause entry into the secure mode.” Ans. 13. Therefore, we agree with the Examiner that Takahashi teaches “executing an activation sequence of instructions beginning at the entry address” and “entering the secure mode of operation only if the activation sequence of instructions is fully executed by the CPU in a pre-defined order.” Appellants also argue that applying Takahashi to the Boebert-Veil combination would render the Boebert-Veil system inoperable for its intended purpose. App. Br. 17. Appellants assert that integration of just Takashi’s interrupt handling would result in a “secure mode [that] is in fact not secure, because according to the Takahashi approach, there is no check that the interrupt itself is legitimate.” App. Br. 20. Appellants further assert that if the security method of Takahashi is fully incorporated into the Boebert-Veil system, “then all input/output is disabled, which defeats the operation of the system including a display and a separate secure mode indicator.” Id. Appeal 2010-004003 Application 11/322,893 7 As the Examiner stated, Takahashi is “merely relied upon for the teaching of the method of activating a secure mode,” such that one skilled in the art would incorporate the teachings from Takahashi into the Boebert- Veil system. Ans. 14, 19. The specific activation sequence of Takahashi is not relevant, as one of ordinary skill in the art would have found it obvious to use Takahashi’s teaching of an activation sequence in order to enter a secure mode that would be appropriate for the Boebert-Veil system. We emphasize: To justify combining reference teachings in support of a rejection it is not necessary that a device shown in one reference can be physically inserted into the device shown in the other. The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference; nor is it that the claimed invention must be expressly suggested in any one or all of the references. Rather, the test is what the combined teachings of the references would have suggested to those of ordinary skill in the art. In re Keller, 642 F.2d 413, 425 (CCPA 1981) (citations omitted). It is the integration, not the bodily incorporation, of the teachings of Takahashi into the Boebert-Veil system that would result in rendering Appellants’ claimed invention obvious to one of ordinary skill in the art (and operable for its intended purpose). Therefore, we are not persuaded by Appellants’ arguments that one would lack motivation to combine Takahashi with the Boebert-Veil system or that incorporating Takahashi’s teachings into the Boebert-Veil system would render Fitz inoperable for its intended use. For the same reasons as discussed above, we find that the combination would have been obvious with respect to dependent claim 3, notwithstanding Appeal 2010-004003 Application 11/322,893 8 Appellants’ arguments that the combination would have been “even less obvious.” App. Br. 21. Appellants have not argued dependent claims 4, 6, and 9-11 separately. Therefore, we agree with the Examiner that claims 3, 4- 6, 9-11, and 13-19 are obvious. ISSUE 35 U.S.C. § 103(a) (Boebert, Veil, Takahashi, and Hobson): claims 7 and 8 Appellants argue that Hobson is directed to “operations that are performed by a digital system once already in a secure mode, and not in order to enter the secure mode.” App. Br. 23-24. Therefore, Appellants argue that Hobson does not teach monitoring status signals or aborting an activation sequence. Issue 2: Has the Examiner erred in finding that Hobson, in combination with Boebert, Veil, and Takahashi teaches or suggests “monitoring a set of one or more status signals provided by the CPU and the system during each access of the activation sequence” and “aborting the activation sequence if the status signals indicate that any one of the activation sequence accesses is not an instruction fetch access,” as recited in claim 7? ANALYSIS Appellants argue that Hobson’s control bit is used when the system is already in secure mode as opposed to being used in order to enter a secure mode. App. Br. 26. Appellants assert that this use of a control bit in Hobson therefore has no application to the claimed activation sequence. Id. Appeal 2010-004003 Application 11/322,893 9 Appellants further argue that Hobson does not discuss aborting if a store operation is requested and merely prevents the store operation from executing. Id. We agree with the Examiner’s findings and conclusions. Ans. 8. The Examiner is merely relying on Hobson to teach monitoring status signals (i.e., setting and checking the fetch-only control bit), and aborting instructions when those signals are violated, which prevents write instructions from otherwise being executed. Id. We find integrating the teachings of Hobson into the activation sequence based on the motivation provided would have been obvious. Therefore, we agree with the Examiner that claim 7 and claim 8, not separately argued, are obvious in view of Boebert, Veil, Takahashi, and Hobson. DECISION The Examiner’s rejection of claims 3-11 and 13-19 under 35 U.S.C. § 103(a) as being obvious 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 msc