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  <xsd:element abstract="true" id="smsi_WarrantsIssuedWithConvertibleNotesMember" name="WarrantsIssuedWithConvertibleNotesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-10-revenues-disaggregation-of-revenue-details" name="statement-statement-note-10-revenues-disaggregation-of-revenue-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-10-revenues-tables" name="statement-statement-note-10-revenues-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-11-segment-customer-concentration-and-geographical-information-schedule-of-expenses-details" name="statement-statement-note-11-segment-customer-concentration-and-geographical-information-schedule-of-expenses-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-11-segment-customer-concentration-and-geographical-information-schedule-of-geographical-information-details" name="statement-statement-note-11-segment-customer-concentration-and-geographical-information-schedule-of-geographical-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-11-segment-customer-concentration-and-geographical-information-schedule-of-revenue-details" name="statement-statement-note-11-segment-customer-concentration-and-geographical-information-schedule-of-revenue-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-11-segment-customer-concentration-and-geographical-information-tables" name="statement-statement-note-11-segment-customer-concentration-and-geographical-information-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-13-leases-lease-costs-details" name="statement-statement-note-13-leases-lease-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-13-leases-schedule-of-lease-liability-maturity-details" name="statement-statement-note-13-leases-schedule-of-lease-liability-maturity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-13-leases-tables" name="statement-statement-note-13-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-5-debt-and-warrants-transactions-tables" name="statement-statement-note-5-debt-and-warrants-transactions-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-5-debt-and-warrants-transactions-warrant-valuation-assumptions-details" name="statement-statement-note-5-debt-and-warrants-transactions-warrant-valuation-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-6-fair-value-of-financial-instruments-changes-in-derivative-liabilities-details" name="statement-statement-note-6-fair-value-of-financial-instruments-changes-in-derivative-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-6-fair-value-of-financial-instruments-liabilities-measure-on-recurring-basis-details" name="statement-statement-note-6-fair-value-of-financial-instruments-liabilities-measure-on-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-6-fair-value-of-financial-instruments-tables" name="statement-statement-note-6-fair-value-of-financial-instruments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-7-goodwill-and-intangible-assets-future-amortization-expense-details" name="statement-statement-note-7-goodwill-and-intangible-assets-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-7-goodwill-and-intangible-assets-schedule-of-intangible-assets-details" name="statement-statement-note-7-goodwill-and-intangible-assets-schedule-of-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-7-goodwill-and-intangible-assets-tables" name="statement-statement-note-7-goodwill-and-intangible-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-8-earnings-per-share-schedule-of-antidilutive-securities-details" name="statement-statement-note-8-earnings-per-share-schedule-of-antidilutive-securities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-8-earnings-per-share-schedule-of-earnings-per-share-details" name="statement-statement-note-8-earnings-per-share-schedule-of-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-8-earnings-per-share-tables" name="statement-statement-note-8-earnings-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-9-stockbased-compensation-restricted-stock-activity-details" name="statement-statement-note-9-stockbased-compensation-restricted-stock-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-9-stockbased-compensation-schedule-of-stock-based-compensation-details" name="statement-statement-note-9-stockbased-compensation-schedule-of-stock-based-compensation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-9-stockbased-compensation-schedule-of-stock-options-details" name="statement-statement-note-9-stockbased-compensation-schedule-of-stock-options-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-note-9-stockbased-compensation-tables" name="statement-statement-note-9-stockbased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="smsi_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
