<element name="SenderDigitalEnvelope"> <complexType> <sequence> <element name="DigitalEnvelopeProtocol" type="tns:protocol.type" /> <element ref="tns:EncryptionAlgorithm" maxOccurs="unbounded" /> <element name="EncryptionSecurityDetailsRef" type="tns:SecurityDetailsRef.type" minOccurs="0" /> </sequence> </complexType> </element>