Encoding at end of method name

When I create a new SOAP project (File > New SOAP Project) in SOAPUI5.2.1 and open a request in the request editor, the method name is suffixed with what looks like a base64 encoding, i.e. "FClwamF23S9sYW5nLbN0cmluzs=" in the example below. What is this and how is it generated?

Thanks,

Ian

<soapenv:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:view="http://example.com/a/b/c/d/ImplementingClass#getVersion?FClwamF23S9sYW5nLbN0cmluzs=">
<soapenv:Header/>
<soapenv:Body>
<view:getVersion soapenv:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"/>
</soapenv:Body>
</soapenv:Envelope>