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  <xsd:element id="ftnt_ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsAndAllocationOfRecognizedPeriodCostsTableTextBlock" name="ScheduleOfShareBasedPaymentAwardStockOptionsValuationAssumptionsAndAllocationOfRecognizedPeriodCostsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ScheduleOfSharesReservedForFutureIssuanceTableTextBlock" name="ScheduleOfSharesReservedForFutureIssuanceTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ScheduleOfWarrantiesTable" name="ScheduleOfWarrantiesTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ServicesGrossProfit" name="ServicesGrossProfit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ServicesMember" name="ServicesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesAxis" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesDomain" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAuthorizedSharesChangesDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardExpirationPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVest" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsExpectedToVestWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsIssuedWeightedAveragePricePerShare" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsIssuedWeightedAveragePricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximum" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximumPercent" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseToNumberOfSharesAuthorizedPerOriginalPlanTermsMaximumPercent" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumStockOwnershipPercentForOptionsGrantedToIndividuals" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMaximumStockOwnershipPercentForOptionsGrantedToIndividuals" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExericsePriceAsPercentOfFairValueOnGrantDate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumExericsePriceAsPercentOfFairValueOnGrantDate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumStockOwnershipPercentTriggeringEarlyAwardExpiration" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardMinimumStockOwnershipPercentTriggeringEarlyAwardExpiration" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="ftnt_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedBeforeAdjustments" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedBeforeAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfFixedAmountOfSharesMember" name="ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfFixedAmountOfSharesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfOutstandingSharesOnLastDayOfPreceedingYearMember" name="ShareBasedCompensationAwardAuthorizedNumberChangesLesserOfOutstandingSharesOnLastDayOfPreceedingYearMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_ShortTermInvestmentsLineItemMember" name="ShortTermInvestmentsLineItemMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_SoftwareProductWarrantyMember" name="SoftwareProductWarrantyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StateJurisdictionCaliforniaMember" name="StateJurisdictionCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_StockIssuedDuringPeriodSharesStockOptionsAndWarrantsExercised" name="StockIssuedDuringPeriodSharesStockOptionsAndWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_StockIssuedDuringPeriodValueStockOptionsAndWarrantsExercised" name="StockIssuedDuringPeriodValueStockOptionsAndWarrantsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockOptionsAndRestrictedStockUnitsOutstandingMember" name="StockOptionsAndRestrictedStockUnitsOutstandingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockOptionsNonqualifyingMember" name="StockOptionsNonqualifyingMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockPlan2000Member" name="StockPlan2000Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockPlan2008Member" name="StockPlan2008Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockPlan2009Member" name="StockPlan2009Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_StockPlans20002008And2009Member" name="StockPlans20002008And2009Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_TalkswitchCorpMember" name="TalkswitchCorpMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_TechnologyBasedIntangibleAssetsMember" name="TechnologyBasedIntangibleAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_WarrantiesLineItems" name="WarrantiesLineItems" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="ftnt_WarrantyLength" name="WarrantyLength" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="ftnt_XdnIncMember" name="XdnIncMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
