How to generate a WSDL Url without authentication

Hello Expert

I am migrating from PI 7.0 to PO 7.4 dual stack.

My scenario is SOAP+ RFC.  In PI 7.0 customer generate WSDL without authorization using url http://url:port/sap/xi/engine?type=entry&version=3.0&Sender.Service=XX&Interface=urn:xx.com^MI_XX.  But in PO 7.4 I use the same way to generate the WSDL which need input user and password.  User and password requirement means the third party system who call our sender SOAP aggreement need to change their program. Is there solution to disable authorization in PO 7.4.

Thanks in advanced.