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<!-- DFS ActiveDisclosure(SM) XBRL Linkbase Document - http://www.dfsco.com/financial-services/ -->
<!-- Creation Date      : 2018-05-09T19:42:31.2093731+00:00 -->
<!-- Version            : 2.9.6605.1333 -->
<!-- Package ID         : b934e5ecd38940d79e4236ef4b199cfa -->
<!-- Copyright (c) 2018 Donnelley Financial, LLC. All Rights Reserved. -->
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Goodwill" xlink:type="locator" xlink:label="us-gaap_Goodwill" />
    <label xml:lang="en-US" xlink:label="us-gaap_Goodwill_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Goodwill</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_Goodwill_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Goodwill</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other assets</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Other Assets Noncurrent</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_LongTermInvestments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Long-term investments</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_LongTermInvestments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Long Term Investments</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">LIABILITIES AND STOCKHOLDERS&#8217; EQUITY</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities And Stockholders Equity [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:type="locator" xlink:label="us-gaap_LiabilitiesCurrentAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Current Liabilities</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities Current [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:type="locator" xlink:label="us-gaap_AccountsPayableCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsPayableCurrent" xlink:to="us-gaap_AccountsPayableCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Accounts Payable Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:type="locator" xlink:label="us-gaap_DeferredRevenueCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Unearned revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueCurrent" xlink:to="us-gaap_DeferredRevenueCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:type="locator" xlink:label="us-gaap_AccruedLiabilitiesCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccruedLiabilitiesCurrent" xlink:to="us-gaap_AccruedLiabilitiesCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AccruedLiabilitiesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Liabilities Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:type="locator" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued wages and benefits</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:to="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Employee Related Liabilities Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccruedIncomeTaxesCurrent" xlink:type="locator" xlink:label="us-gaap_AccruedIncomeTaxesCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax payable</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccruedIncomeTaxesCurrent" xlink:to="us-gaap_AccruedIncomeTaxesCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Accrued Income Taxes Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:type="locator" xlink:label="us-gaap_LiabilitiesCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Current Liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrent" xlink:to="us-gaap_LiabilitiesCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueNoncurrent" xlink:type="locator" xlink:label="us-gaap_DeferredRevenueNoncurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Non-current unearned revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueNoncurrent" xlink:to="us-gaap_DeferredRevenueNoncurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DeferredRevenueNoncurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue Noncurrent</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:type="locator" xlink:label="us-gaap_OtherLiabilitiesNoncurrent" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesNoncurrent" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Other Liabilities Noncurrent</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:type="locator" xlink:label="us-gaap_LongTermDebtNoncurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Bonds payable</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtNoncurrent" xlink:to="us-gaap_LongTermDebtNoncurrent_lbl" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Liabilities" xlink:type="locator" xlink:label="us-gaap_Liabilities" />
    <label xml:lang="en-US" xlink:label="us-gaap_Liabilities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total Liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Liabilities" xlink:to="us-gaap_Liabilities_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_Liabilities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:type="locator" xlink:label="us-gaap_CommitmentsAndContingencies" />
    <label xml:lang="en-US" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Commitments and contingencies (see Note 15)</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Commitments And Contingencies</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:type="locator" xlink:label="us-gaap_StockholdersEquityAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stockholders&#8217; Equity</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockValue" xlink:type="locator" xlink:label="us-gaap_CommonStockValue" />
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    <label xml:lang="en-US" xlink:label="us-gaap_CommonStockValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Common Stock Value</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Additional paid-in capital</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Liabilities And Stockholders Equity</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossNetOfTax" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:to="us-gaap_OtherComprehensiveIncomeLossNetOfTax_lbl" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:type="locator" xlink:label="us-gaap_StatementOfCashFlowsAbstract" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentIncomeAmortizationOfPremium" xlink:type="locator" xlink:label="us-gaap_InvestmentIncomeAmortizationOfPremium" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:type="locator" xlink:label="us-gaap_GainLossOnSaleOfPropertyPlantEquipment" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensation" />
    <label xml:lang="en-US" xlink:label="us-gaap_ShareBasedCompensation_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock-based compensation expense</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInInventories" />
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    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInInventories_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Inventories</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Prepaid expenses and other assets</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Prepaid Deferred Expense And Other Assets</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accounts payable</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Accounts Payable</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInOtherAccruedLiabilities" xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Accrued expenses and other liabilities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities" xlink:to="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInOtherAccruedLiabilities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Other Accrued Liabilities</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable" xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Income tax payable</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable" xlink:to="us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Increase Decrease In Accrued Income Taxes Payable</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash provided by operating activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided By Used In Operating Activities Continuing Operations</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from investing activities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperationsAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided By Used In Investing Activities Continuing Operations [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:type="locator" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of property, plant and equipment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Payments To Acquire Property Plant And Equipment</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:type="locator" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from disposals of property, plant and equipment</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Sale Of Property Plant And Equipment</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities" xlink:type="locator" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from sales and maturities of available-for-sale investments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities" xlink:to="us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Sale And Maturity Of Available For Sale Securities</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecurities" xlink:type="locator" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecurities" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of available-for-sale investments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireAvailableForSaleSecurities" xlink:to="us-gaap_PaymentsToAcquireAvailableForSaleSecurities_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Payments To Acquire Available For Sale Securities</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:type="locator" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Acquisition of business</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireBusinessesGross" xlink:to="us-gaap_PaymentsToAcquireBusinessesGross_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Payments To Acquire Businesses Gross</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in investing activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided By Used In Investing Activities Continuing Operations</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Cash flows from financing activities:</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperationsAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided By Used In Financing Activities Continuing Operations [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:type="locator" xlink:label="us-gaap_ProceedsFromStockOptionsExercised" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Proceeds from stock option exercises</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromStockOptionsExercised" xlink:to="us-gaap_ProceedsFromStockOptionsExercised_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Proceeds From Stock Options Exercised</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:type="locator" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Purchases of treasury stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:to="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsForRepurchaseOfCommonStock_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Payments For Repurchase Of Common Stock</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PaymentsOfDividendsCommonStock" xlink:type="locator" xlink:label="us-gaap_PaymentsOfDividendsCommonStock" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsOfDividendsCommonStock_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Dividend payments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsOfDividendsCommonStock" xlink:to="us-gaap_PaymentsOfDividendsCommonStock_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_PaymentsOfDividendsCommonStock_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Payments Of Dividends Common Stock</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net cash used in financing activities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Net Cash Provided By Used In Financing Activities Continuing Operations</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" xlink:type="locator" xlink:label="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" />
    <label xml:lang="en-US" xlink:label="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net decrease in cash and cash equivalents</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect" xlink:to="us-gaap_CashAndCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect_lbl" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents" xlink:type="locator" xlink:label="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents" />
    <label xml:lang="en-US" xlink:label="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of exchange rate changes</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents" xlink:to="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_EffectOfExchangeRateOnCashAndCashEquivalents_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Effect Of Exchange Rate On Cash And Cash Equivalents</label>
    <label xml:lang="en-US" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Cash and cash equivalents, beginning of period</label>
    <label xml:lang="en-US" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Cash and cash equivalents, end of period</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" xlink:type="locator" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Supplemental disclosure of non-cash investing activities:</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_CashFlowNoncashInvestingAndFinancingActivitiesDisclosureAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Cash Flow Noncash Investing And Financing Activities Disclosure [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1" xlink:type="locator" xlink:label="us-gaap_NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1" />
    <label xml:lang="en-US" xlink:label="us-gaap_NoncashOrPartNoncashAcquisitionValueOfAssetsAcquired1_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Purchases of property, plant and equipment included in accounts payable</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual" xlink:type="locator" xlink:label="us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual" />
    <label xml:lang="en-US" xlink:label="us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Net loss</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Business Combination Pro Forma Information Earnings Or Loss Of Acquiree Since Acquisition Date Actual</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" />
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    <label xml:lang="en-US" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets By Major Class [Axis]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" />
    <label xml:lang="en-US" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Finite-Lived Intangible Assets, Major Class Name</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Finite Lived Intangible Assets Major Class Name [Domain]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:type="locator" xlink:label="us-gaap_CustomerRelationshipsMember" />
    <label xml:lang="en-US" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Relationships [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CustomerRelationshipsMember" xlink:to="us-gaap_CustomerRelationshipsMember_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_CustomerRelationshipsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Customer Relationships [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LicensingAgreementsMember" xlink:type="locator" xlink:label="us-gaap_LicensingAgreementsMember" />
    <label xml:lang="en-US" xlink:label="us-gaap_LicensingAgreementsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Licensed Technology [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LicensingAgreementsMember" xlink:to="us-gaap_LicensingAgreementsMember_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_LicensingAgreementsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Licensing Agreements [Member]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_SupplierRelationshipMember" xlink:type="locator" xlink:label="adtn_SupplierRelationshipMember" />
    <label xml:lang="en-US" xlink:label="adtn_SupplierRelationshipMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Supplier relationship.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_SupplierRelationshipMember" xlink:to="adtn_SupplierRelationshipMember_lbl" />
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    <label xml:lang="en-US" xlink:label="adtn_SupplierRelationshipMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Supplier Relationship [Member]</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" xlink:type="locator" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife" />
    <label xml:lang="en-US" xlink:label="us-gaap_AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Life (years)</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionsProFormaRevenue" xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue" />
    <label xml:lang="en-US" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Pro forma revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_BusinessAcquisitionsProFormaRevenue" xlink:to="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_BusinessAcquisitionsProFormaRevenue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisitions Pro Forma Revenue</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic" xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic" />
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    <label xml:lang="en-US" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareBasic_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Business Acquisition Pro Forma Earnings Per Share Basic</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted" xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionProFormaEarningsPerShareDiluted" />
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    <loc xlink:href="adtn-20180331.xsd#adtn_BusinessCombinationAcquisitionAndIntegrationRelatedCostsAndAmortizationOfAcquiredIntangibles" xlink:type="locator" xlink:label="adtn_BusinessCombinationAcquisitionAndIntegrationRelatedCostsAndAmortizationOfAcquiredIntangibles" />
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    <loc xlink:href="adtn-20180331.xsd#adtn_RevenueLineItems" xlink:type="locator" xlink:label="adtn_RevenueLineItems" />
    <label xml:lang="en-US" xlink:label="adtn_RevenueLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue.</label>
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    <loc xlink:href="adtn-20180331.xsd#adtn_RevenueTable" xlink:type="locator" xlink:label="adtn_RevenueTable" />
    <label xml:lang="en-US" xlink:label="adtn_RevenueTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Revenue.</label>
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    <label xml:lang="en-US" xlink:label="adtn_RevenueTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue [Table]</label>
    <label xml:lang="en-US" xlink:label="adtn_RevenueTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Table]</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_RangeAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_RangeAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Range [Axis]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeMember" xlink:type="locator" xlink:label="us-gaap_RangeMember" />
    <label xml:lang="en-US" xlink:label="us-gaap_RangeMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Range</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_RangeMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Range [Member]</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_MinimumMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Minimum [Member]</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_MinimumMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Minimum [Member]</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_MaximumMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maximum [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MaximumMember" xlink:to="us-gaap_MaximumMember_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_MaximumMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Maximum [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_RevenueLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue [Line Items]</label>
    <label xml:lang="en-US" xlink:label="adtn_RevenueLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Revenue [Line Items]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StandardProductWarrantyDescription" xlink:type="locator" xlink:label="us-gaap_StandardProductWarrantyDescription" />
    <label xml:lang="en-US" xlink:label="us-gaap_StandardProductWarrantyDescription_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Period of assurance-based warranty for product defects</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StandardProductWarrantyDescription" xlink:to="us-gaap_StandardProductWarrantyDescription_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_StandardProductWarrantyDescription_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Standard Product Warranty Description</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment" xlink:type="locator" xlink:label="adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment" />
    <label xml:lang="en-US" xlink:label="adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Lessor sales type lease arrangement terms for network equipment.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment" xlink:to="adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Lessor sales type lease arrangement terms for network equipments</label>
    <label xml:lang="en-US" xlink:label="adtn_LessorSalesTypeLeaseArrangementTermsForNetworkEquipment_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Lessor Sales Type Lease Arrangement Terms For Network Equipment</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_MaintenanceServicePeriods" xlink:type="locator" xlink:label="adtn_MaintenanceServicePeriods" />
    <label xml:lang="en-US" xlink:label="adtn_MaintenanceServicePeriods_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Maintenance service periods.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_MaintenanceServicePeriods" xlink:to="adtn_MaintenanceServicePeriods_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_MaintenanceServicePeriods_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Maintenance service periods</label>
    <label xml:lang="en-US" xlink:label="adtn_MaintenanceServicePeriods_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Maintenance Service Periods</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRemainingPerformanceObligation" xlink:type="locator" xlink:label="us-gaap_RevenueRemainingPerformanceObligation" />
    <label xml:lang="en-US" xlink:label="us-gaap_RevenueRemainingPerformanceObligation_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Remaining performance obligations</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RevenueRemainingPerformanceObligation" xlink:to="us-gaap_RevenueRemainingPerformanceObligation_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_RevenueRemainingPerformanceObligation_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Revenue Remaining Performance Obligation</label>
    <label xml:lang="en-US" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Accounts receivable</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContractWithCustomerAssetNetCurrent" xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent" />
    <label xml:lang="en-US" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contract assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ContractWithCustomerAssetNetCurrent" xlink:to="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Contract With Customer Asset Net Current</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueRevenueRecognized1" xlink:type="locator" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1" />
    <label xml:lang="en-US" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue recognized that was included in unearned revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueRevenueRecognized1" xlink:to="us-gaap_DeferredRevenueRevenueRecognized1_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DeferredRevenueRevenueRecognized1_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Deferred Revenue Revenue Recognized1</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:type="locator" xlink:label="us-gaap_DisaggregationOfRevenueTable" />
    <label xml:lang="en-US" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disaggregation Of Revenue [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DisaggregationOfRevenueTable" xlink:to="us-gaap_DisaggregationOfRevenueTable_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DisaggregationOfRevenueTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation Of Revenue [Table]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:type="locator" xlink:label="us-gaap_StatementBusinessSegmentsAxis" />
    <label xml:lang="en-US" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_StatementBusinessSegmentsAxis_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Statement Business Segments [Axis]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentDomain" xlink:type="locator" xlink:label="us-gaap_SegmentDomain" />
    <label xml:lang="en-US" xlink:label="us-gaap_SegmentDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentDomain" xlink:to="us-gaap_SegmentDomain_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_SegmentDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Segment [Domain]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_NetworkSolutionsMember" xlink:type="locator" xlink:label="adtn_NetworkSolutionsMember" />
    <label xml:lang="en-US" xlink:label="adtn_NetworkSolutionsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Network solutions.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_NetworkSolutionsMember" xlink:to="adtn_NetworkSolutionsMember_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_NetworkSolutionsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Network Solutions [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_NetworkSolutionsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Network Solutions [Member]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_ServicesAndSupportMember" xlink:type="locator" xlink:label="adtn_ServicesAndSupportMember" />
    <label xml:lang="en-US" xlink:label="adtn_ServicesAndSupportMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Services and support.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_ServicesAndSupportMember" xlink:to="adtn_ServicesAndSupportMember_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_ServicesAndSupportMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Services &amp; Support [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_ServicesAndSupportMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Services And Support [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:type="locator" xlink:label="us-gaap_ProductOrServiceAxis" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductOrServiceAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Products and Services</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProductOrServiceAxis" xlink:to="us-gaap_ProductOrServiceAxis_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductOrServiceAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Product Or Service [Axis]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:type="locator" xlink:label="us-gaap_ProductsAndServicesDomain" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductsAndServicesDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Products and Services</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProductsAndServicesDomain" xlink:to="us-gaap_ProductsAndServicesDomain_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductsAndServicesDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Products And Services [Domain]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_AccessAndAggregationMember" xlink:type="locator" xlink:label="adtn_AccessAndAggregationMember" />
    <label xml:lang="en-US" xlink:label="adtn_AccessAndAggregationMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Access and aggregation.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_AccessAndAggregationMember" xlink:to="adtn_AccessAndAggregationMember_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_AccessAndAggregationMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Access &amp; Aggregation [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_AccessAndAggregationMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Access And Aggregation [Member]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_CustomerDevicesMember" xlink:type="locator" xlink:label="adtn_CustomerDevicesMember" />
    <label xml:lang="en-US" xlink:label="adtn_CustomerDevicesMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Customer devices.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_CustomerDevicesMember" xlink:to="adtn_CustomerDevicesMember_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_CustomerDevicesMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Customer Devices [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_CustomerDevicesMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Customer Devices [Member]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_TraditionalAndOtherProductsMember" xlink:type="locator" xlink:label="adtn_TraditionalAndOtherProductsMember" />
    <label xml:lang="en-US" xlink:label="adtn_TraditionalAndOtherProductsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Traditional and other products.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_TraditionalAndOtherProductsMember" xlink:to="adtn_TraditionalAndOtherProductsMember_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_TraditionalAndOtherProductsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Traditional &amp; Other Products [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_TraditionalAndOtherProductsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Traditional And Other Products [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:type="locator" xlink:label="us-gaap_DisaggregationOfRevenueLineItems" />
    <label xml:lang="en-US" xlink:label="us-gaap_DisaggregationOfRevenueLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Disaggregation Of Revenue [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DisaggregationOfRevenueLineItems" xlink:to="us-gaap_DisaggregationOfRevenueLineItems_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DisaggregationOfRevenueLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Disaggregation Of Revenue [Line Items]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:type="locator" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" />
    <label xml:lang="en-US" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Revenue From Contract With Customer Excluding Assessed Tax</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:type="locator" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations" />
    <label xml:lang="en-US" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effective tax rate</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:to="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_EffectiveIncomeTaxRateContinuingOperations_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Effective Income Tax Rate Continuing Operations</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanServiceCost" xlink:type="locator" xlink:label="us-gaap_DefinedBenefitPlanServiceCost" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanServiceCost_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Service cost</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanServiceCost" xlink:to="us-gaap_DefinedBenefitPlanServiceCost_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanServiceCost_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Service Cost</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanInterestCost" xlink:type="locator" xlink:label="us-gaap_DefinedBenefitPlanInterestCost" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanInterestCost_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Interest cost</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanInterestCost" xlink:to="us-gaap_DefinedBenefitPlanInterestCost_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanInterestCost_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Interest Cost</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:type="locator" xlink:label="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Expected return on plan assets</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:to="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Expected Return On Plan Assets</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:type="locator" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Amortization of actuarial losses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:to="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Amortization Of Gains Losses</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:type="locator" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Net periodic pension cost</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:to="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Defined Benefit Plan Net Periodic Benefit Cost</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:type="locator" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" />
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    <label xml:lang="en-US" xlink:label="us-gaap_USTreasuryAndGovernmentMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">U S Treasury And Government [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:type="locator" xlink:label="us-gaap_ForeignGovernmentDebtSecuritiesMember" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ForeignGovernmentDebtSecuritiesMember" xlink:to="us-gaap_ForeignGovernmentDebtSecuritiesMember_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ForeignGovernmentDebtSecuritiesMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Foreign Government Debt Securities [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" xlink:type="locator" xlink:label="us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule of Available-for-sale Securities [Line Items]</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Available For Sale Securities [Line Items]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Amortized Cost</label>
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    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Debt Securities Amortized Cost Basis</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Unrealized Gains</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:to="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gross Unrealized Losses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:to="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Available-for-sale debt securities, Carrying Value</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:to="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Securities</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedInvestments" xlink:type="locator" xlink:label="us-gaap_RestrictedInvestments" />
    <label xml:lang="en-US" xlink:label="us-gaap_RestrictedInvestments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Restricted investment held at cost</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RestrictedInvestments" xlink:to="us-gaap_RestrictedInvestments_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_RestrictedInvestments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Restricted Investments</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherInvestments" xlink:type="locator" xlink:label="us-gaap_OtherInvestments" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherInvestments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other investments held at cost</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherInvestments" xlink:to="us-gaap_OtherInvestments_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherInvestments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Other Investments</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Investments" xlink:type="locator" xlink:label="us-gaap_Investments" />
    <label xml:lang="en-US" xlink:label="us-gaap_Investments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Total carrying value of available-for-sale investments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Investments" xlink:to="us-gaap_Investments_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_Investments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Investments</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" xlink:type="locator" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" />
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of available-for-sale debt securities at fair value maturing after one year through two years.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue" xlink:to="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" />
    <loc xlink:href="adtn-20180331.xsd#adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue" xlink:type="locator" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue" />
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of available-for-sale debt securities at fair value maturing after two year through three years.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue" xlink:to="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" />
    <loc xlink:href="adtn-20180331.xsd#adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue" xlink:type="locator" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue" />
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of available-for-sale debt securities at fair value maturing after three years through five years.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue" xlink:to="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue_lbl" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less than one year</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue" xlink:to="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities Within One Year Fair Value</label>
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">One to two years</label>
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughTwoYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After One Through Two Years Fair Value</label>
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Two to three years</label>
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterTwoThroughThreeYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After Two Through Three Years Fair Value</label>
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Three to five years</label>
    <label xml:lang="en-US" xlink:label="adtn_AvailableForSaleSecuritiesDebtMaturitiesAfterThreeThroughFiveYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After Three Through Five Years Fair Value</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Five to ten years</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue" xlink:to="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">More than ten years</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue" xlink:to="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Debt Maturities After Ten Years Fair Value</label>
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Available-for-sale debt securities, Fair Value/Carrying Value</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtSecuritiesMember" xlink:type="locator" xlink:label="us-gaap_DebtSecuritiesMember" />
    <label xml:lang="en-US" xlink:label="us-gaap_DebtSecuritiesMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Debt Securities [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtSecuritiesMember" xlink:to="us-gaap_DebtSecuritiesMember_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_DebtSecuritiesMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Debt Securities [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross realized gains</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains" xlink:to="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedGains_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Gross Realized Gains</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xlink:type="locator" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel">Gross realized losses</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses" xlink:to="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Available For Sale Securities Gross Realized Losses</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FederalHomeLoanBanksAbstract" xlink:type="locator" xlink:label="us-gaap_FederalHomeLoanBanksAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_FederalHomeLoanBanksAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Federal Home Loan Banks [Abstract]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FederalHomeLoanBanksAbstract" xlink:to="us-gaap_FederalHomeLoanBanksAbstract_lbl" />
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfInvestmentsTable" xlink:type="locator" xlink:label="us-gaap_ScheduleOfInvestmentsTable" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfInvestmentsTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Investments [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfInvestmentsTable" xlink:to="us-gaap_ScheduleOfInvestmentsTable_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfInvestmentsTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Investments [Table]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:type="locator" xlink:label="us-gaap_FairValueByAssetClassAxis" />
    <label xml:lang="en-US" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Class</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueByAssetClassAxis" xlink:to="us-gaap_FairValueByAssetClassAxis_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_FairValueByAssetClassAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Fair Value By Asset Class [Axis]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:type="locator" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
    <label xml:lang="en-US" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Asset Class</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_lbl" />
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    <label xml:lang="en-US" xlink:label="adtn_RawMaterialsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Raw materials.</label>
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GoodwillLineItems" xlink:to="us-gaap_GoodwillLineItems_lbl" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" />
    <label xml:lang="en-US" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2020</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" />
    <label xml:lang="en-US" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">2021</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax" xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansNetOfTax" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:type="locator" xlink:label="us-gaap_TreasuryStockValueAcquiredCostMethod" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" xlink:type="locator" xlink:label="us-gaap_AdjustmentToAdditionalPaidInCapitalIncomeTaxEffectFromShareBasedCompensationNet" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:type="locator" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" xlink:type="locator" xlink:label="us-gaap_StockRepurchaseProgramNumberOfSharesAuthorizedToBeRepurchased" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit" xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit" />
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:type="locator" xlink:label="us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" />
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    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLossAbstract" xlink:to="us-gaap_NetIncomeLossAbstract_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NetIncomeLossAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Net Income Loss [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:type="locator" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Denominator</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number Of Shares Outstanding [Abstract]</label>
    <label xml:lang="en-US" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Weighted average number of shares &#8211; basic</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract" xlink:type="locator" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract" />
    <label xml:lang="en-US" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Effect of dilutive securities</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract" xlink:to="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Weighted Average Number Diluted Shares Outstanding Adjustment [Abstract]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:type="locator" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Stock options</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:to="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable To Share Based Payment Arrangements</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncrementalCommonSharesAttributableToContingentlyIssuableShares" xlink:type="locator" xlink:label="us-gaap_IncrementalCommonSharesAttributableToContingentlyIssuableShares" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncrementalCommonSharesAttributableToContingentlyIssuableShares_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">PSUs, RSUs and restricted stock</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncrementalCommonSharesAttributableToContingentlyIssuableShares" xlink:to="us-gaap_IncrementalCommonSharesAttributableToContingentlyIssuableShares_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_IncrementalCommonSharesAttributableToContingentlyIssuableShares_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Incremental Common Shares Attributable To Contingently Issuable Shares</label>
    <label xml:lang="en-US" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel">Weighted average number of shares &#8211; diluted</label>
    <label xml:lang="en-US" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income (loss) per share &#8211; basic</label>
    <label xml:lang="en-US" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel">Net income (loss) per share &#8211; diluted</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" />
    <label xml:lang="en-US" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Anti-dilutive options, Total</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NumberOfReportableSegments" xlink:type="locator" xlink:label="us-gaap_NumberOfReportableSegments" />
    <label xml:lang="en-US" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of reportable segments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NumberOfReportableSegments" xlink:to="us-gaap_NumberOfReportableSegments_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Reportable Segments</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:type="locator" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Segment Reporting Information By Segment [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:to="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Segment Reporting Information By Segment [Table]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:type="locator" xlink:label="us-gaap_SegmentReportingInformationLineItems" />
    <label xml:lang="en-US" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Segment Reporting Information [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_SegmentReportingInformationLineItems_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Segment Reporting Information [Line Items]</label>
    <label xml:lang="en-US" xlink:label="us-gaap_SalesRevenueNet_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Sales</label>
    <label xml:lang="en-US" xlink:label="us-gaap_GrossProfit_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Gross Profit</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_NumberOfProductCategories" xlink:type="locator" xlink:label="adtn_NumberOfProductCategories" />
    <label xml:lang="en-US" xlink:label="adtn_NumberOfProductCategories_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Sales information by product category.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_NumberOfProductCategories" xlink:to="adtn_NumberOfProductCategories_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_NumberOfProductCategories_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Number of categories</label>
    <label xml:lang="en-US" xlink:label="adtn_NumberOfProductCategories_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Number Of Product Categories</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:type="locator" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Schedule Of Entity Wide Information Revenue From External Customers By Products And Services [Table]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:to="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Schedule Of Entity Wide Information Revenue From External Customers By Products And Services [Table]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_AccessAndAggregationsMember" xlink:type="locator" xlink:label="adtn_AccessAndAggregationsMember" />
    <label xml:lang="en-US" xlink:label="adtn_AccessAndAggregationsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Access and aggregations.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_AccessAndAggregationsMember" xlink:to="adtn_AccessAndAggregationsMember_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_AccessAndAggregationsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Access &amp; Aggregation [Member]</label>
    <label xml:lang="en-US" xlink:label="adtn_AccessAndAggregationsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Access And Aggregations [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems" xlink:type="locator" xlink:label="us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems" />
    <label xml:lang="en-US" xlink:label="us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Revenue from External Customer [Line Items]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems" xlink:to="us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Entity Wide Information Revenue From External Customer [Line Items]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProductWarrantyAccrual" xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrual" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Liability for warranty obligations</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProductWarrantyAccrual" xlink:to="us-gaap_ProductWarrantyAccrual_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Accrual</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued" xlink:type="locator" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued" />
    <label xml:lang="en-US" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Product warranty accrual increase decrease for warranties issued.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued" xlink:to="adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued_lbl" />
    <loc xlink:href="adtn-20180331.xsd#adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments" xlink:type="locator" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments" />
    <label xml:lang="en-US" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Product warranty accrual increase decrease for payments.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments" xlink:to="adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel">Balance at beginning of period</label>
    <label xml:lang="en-US" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Plus: Amounts charged to cost and expenses</label>
    <label xml:lang="en-US" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForWarrantiesIssued_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Accrual Increase Decrease For Warranties Issued</label>
    <label xml:lang="en-US" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Less: Deductions</label>
    <label xml:lang="en-US" xlink:label="adtn_ProductWarrantyAccrualIncreaseDecreaseForPayments_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Product Warranty Accrual Increase Decrease For Payments</label>
    <label xml:lang="en-US" xlink:label="us-gaap_ProductWarrantyAccrual_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel">Balance at end of period</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_NumberOfPrivateEquityFunds" xlink:type="locator" xlink:label="adtn_NumberOfPrivateEquityFunds" />
    <label xml:lang="en-US" xlink:label="adtn_NumberOfPrivateEquityFunds_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">The number of investments in private equity funds.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_NumberOfPrivateEquityFunds" xlink:to="adtn_NumberOfPrivateEquityFunds_lbl" />
    <loc xlink:href="adtn-20180331.xsd#adtn_CommitmentsTowardsPrivateEquityFunds" xlink:type="locator" xlink:label="adtn_CommitmentsTowardsPrivateEquityFunds" />
    <label xml:lang="en-US" xlink:label="adtn_CommitmentsTowardsPrivateEquityFunds_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Amount of contributions made that have been applied to private equity fund commitments.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_CommitmentsTowardsPrivateEquityFunds" xlink:to="adtn_CommitmentsTowardsPrivateEquityFunds_lbl" />
    <loc xlink:href="adtn-20180331.xsd#adtn_ContingenciesAndCommitmentsLineItems" xlink:type="locator" xlink:label="adtn_ContingenciesAndCommitmentsLineItems" />
    <label xml:lang="en-US" xlink:label="adtn_ContingenciesAndCommitmentsLineItems_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingencies and commitments.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_ContingenciesAndCommitmentsLineItems" xlink:to="adtn_ContingenciesAndCommitmentsLineItems_lbl" />
    <loc xlink:href="adtn-20180331.xsd#adtn_ContingenciesAndCommitmentsTable" xlink:type="locator" xlink:label="adtn_ContingenciesAndCommitmentsTable" />
    <label xml:lang="en-US" xlink:label="adtn_ContingenciesAndCommitmentsTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Contingencies and commitments.</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="adtn_ContingenciesAndCommitmentsTable" xlink:to="adtn_ContingenciesAndCommitmentsTable_lbl" />
    <label xml:lang="en-US" xlink:label="adtn_ContingenciesAndCommitmentsTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Contingencies And Commitments [Table]</label>
    <label xml:lang="en-US" xlink:label="adtn_ContingenciesAndCommitmentsTable_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Contingencies And Commitments [Table]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PrivateEquityFundsMember" xlink:type="locator" xlink:label="us-gaap_PrivateEquityFundsMember" />
    <label xml:lang="en-US" xlink:label="us-gaap_PrivateEquityFundsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Private Equity Funds [Member]</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PrivateEquityFundsMember" xlink:to="us-gaap_PrivateEquityFundsMember_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_PrivateEquityFundsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Private Equity Funds [Member]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherCommitmentsAxis" xlink:type="locator" xlink:label="us-gaap_OtherCommitmentsAxis" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherCommitmentsAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherCommitmentsAxis" xlink:to="us-gaap_OtherCommitmentsAxis_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherCommitmentsAxis_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitments [Axis]</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherCommitmentsDomain" xlink:type="locator" xlink:label="us-gaap_OtherCommitmentsDomain" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherCommitmentsDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel">Other Commitments</label>
    <labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherCommitmentsDomain" xlink:to="us-gaap_OtherCommitmentsDomain_lbl" />
    <label xml:lang="en-US" xlink:label="us-gaap_OtherCommitmentsDomain_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label">Other Commitments [Domain]</label>
    <loc xlink:href="adtn-20180331.xsd#adtn_InvestmentCommitmentsMember" xlink:type="locator" xlink:label="adtn_InvestmentCommitmentsMember" />
    <label xml:lang="en-US" xlink:label="adtn_InvestmentCommitmentsMember_lbl" xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation">Investment commitments.</label>
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