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  <xs:element id="band_CPaaSUsageBasedFeesMember" abstract="true" name="CPaaSUsageBasedFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_CPaaSServiceFeesMember" abstract="true" name="CPaaSServiceFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_StockOptionsAndRestrictedStockUnitsEmployeesMember" abstract="true" name="StockOptionsAndRestrictedStockUnitsEmployeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_RestrictedStockUnitsNonEmployeeMember" abstract="true" name="RestrictedStockUnitsNonEmployeeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_ZeroPointTwoFivePercentConvertibleSeniorNotesDue2026Member" abstract="true" name="ZeroPointTwoFivePercentConvertibleSeniorNotesDue2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_ZeroPointFiveZeroPercentConvertibleSeniorNotesDue2028Member" abstract="true" name="ZeroPointFiveZeroPercentConvertibleSeniorNotesDue2028Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_AccountsReceivableAllowanceForCreditLossForeignCurrencyTranslation" abstract="false" name="AccountsReceivableAllowanceForCreditLossForeignCurrencyTranslation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_CustomerDepositsCurrent1" abstract="false" name="CustomerDepositsCurrent1" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_CorporateHeadquartersMember" abstract="true" name="CorporateHeadquartersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_OperatingLeaseRightOfUseAssetAccumulatedAmortization" abstract="false" name="OperatingLeaseRightOfUseAssetAccumulatedAmortization" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_LesseeOperatingLeaseNumberOfOptionToExtend" abstract="false" name="LesseeOperatingLeaseNumberOfOptionToExtend" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="band_MarketRentalRate" abstract="false" name="MarketRentalRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_LeaseIncentive" abstract="false" name="LeaseIncentive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_ComputerAndOfficeEquipmentMember" abstract="true" name="ComputerAndOfficeEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_TelecommunicationsEquipmentMember" abstract="true" name="TelecommunicationsEquipmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_BankOfAmericaCreditAgreementMember" abstract="true" name="BankOfAmericaCreditAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_VotingCommonStockMember" abstract="true" name="VotingCommonStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_LineOfCreditFacilityAccordionFeatureIncreaseLimit" abstract="false" name="LineOfCreditFacilityAccordionFeatureIncreaseLimit" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_LineOfCreditFacilityDaysPriorToMaturityDate" abstract="false" name="LineOfCreditFacilityDaysPriorToMaturityDate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="band_DebtInstrumentCovenantLeverageRatioMaximumAllowed" abstract="false" name="DebtInstrumentCovenantLeverageRatioMaximumAllowed" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="band_DebtInstrumentCovenantFixedChargeRatioMinimum" abstract="false" name="DebtInstrumentCovenantFixedChargeRatioMinimum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="band_DebtInstrumentCovenantProFormaLeverageRatioMinimum" abstract="false" name="DebtInstrumentCovenantProFormaLeverageRatioMinimum" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="band_LineOfCreditFacilityCovenantConsecutiveQuarters" abstract="false" name="LineOfCreditFacilityCovenantConsecutiveQuarters" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="band_DebtInstrumentCovenantProFormaTotalLeverageRatioMaximumAllowed" abstract="false" name="DebtInstrumentCovenantProFormaTotalLeverageRatioMaximumAllowed" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="band_DebtInstrumentAdditionalBasisSpreadOnVariableRate" abstract="false" name="DebtInstrumentAdditionalBasisSpreadOnVariableRate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_DebtInstrumentCollateralEquityInterestsPledgedPercentageOfCapitalStock" abstract="false" name="DebtInstrumentCollateralEquityInterestsPledgedPercentageOfCapitalStock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="band_DebtInstrumentRedemptionPeriodTradingDaysToMaturity" abstract="false" name="DebtInstrumentRedemptionPeriodTradingDaysToMaturity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="band_DebtInstrumentConvertibleInitialConversionStrikePrice" abstract="false" name="DebtInstrumentConvertibleInitialConversionStrikePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="band_DebtInstrumentConvertibleInitialCapPrice" abstract="false" name="DebtInstrumentConvertibleInitialCapPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="band_CappedCallOptionIssuanceCost" abstract="false" name="CappedCallOptionIssuanceCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_DebtInstrumentConvertibleConversionCappedCallShares" abstract="false" name="DebtInstrumentConvertibleConversionCappedCallShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="band_CommonStockVotingRightsVotesPerShare" abstract="false" name="CommonStockVotingRightsVotesPerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="band_StockOptionPlan2010Member" abstract="true" name="StockOptionPlan2010Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_A2017EquityCompensationPlanMember" abstract="true" name="A2017EquityCompensationPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_CommonStockCapitalSharesReservedForFutureIssuancePercentIncrease" abstract="false" name="CommonStockCapitalSharesReservedForFutureIssuancePercentIncrease" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_OfficeSpaceMember" abstract="true" name="OfficeSpaceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationDeductionInnovationIncomeAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeductionInnovationIncomeAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseNonDeductibleExecutiveCompensationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseNonDeductibleExecutiveCompensationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseIncomeFromBranchAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseIncomeFromBranchAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationDeductionInnovationIncomePercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationDeductionInnovationIncomePercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseNonDeductibleExecutiveCompensationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseNonDeductibleExecutiveCompensationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseIncomeFromBranchPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseIncomeFromBranchPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxesOtherPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxesOtherPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationCostPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseExecutiveCompensationCostPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_EffectiveIncomeTaxRateReconciliationIntangiblesAndDeferredAdjustments" abstract="false" name="EffectiveIncomeTaxRateReconciliationIntangiblesAndDeferredAdjustments" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="band_DeferredTaxAssetsOperatingLeaseArrangements" abstract="false" name="DeferredTaxAssetsOperatingLeaseArrangements" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="band_EarningsPerShareBasicAndDilutedEPSAbstract" abstract="true" name="EarningsPerShareBasicAndDilutedEPSAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="band_DarylE.RaifordMember" abstract="true" name="DarylE.RaifordMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="band_KadeRossMember" abstract="true" name="KadeRossMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
