ASOAP extensions enable developers to modify the request or response streams of SOAP messages
BSOAP extensions are applied to a particular operation with a custom SOAP extension attribute, or registered with the application (or machine) configuration file
CDescription formatters can be created to add custom WSDL extensions, and then read to add these SOAP extension attributes
DHTTP modules and custom Web requests can be used only for a lower level extensibility
EThe Web Services Management for Microsoft .NET (WSM) can enhance .NET Web Services for various Web service protocols that extend beyond the baseline, such as WS-Attachments and WS-Security
FAll of these