VBCS: Securely invoking REST API

Summary

How to pass VBCS logged in user credential to backend REST API

Content

I have developed REST apis using ADF-BC and deployed them in JCS. I have secured those services in weblogic. To invoke those services you need to pass authorization header as

authorization basic <b64 encrypted username:pwd>

I want when VBCS invokes such service, it passes credentials of the person who has logged into VBCS. 

I see various options available in VBCS REST API Authentication.

One option is "Propagate Current User Identity". Although there is no document available but I feel that this option is good enough to pass current VBCS user's credential to REST API.