Secured way of calling REST services in Java Script

Summary:

Hi,

For one use case where we need to construct the END Point URL dynamically, We are doing that in Java script and using Basic Auth as authentication mechanism. We are storing user name and password in ATP table and using the same to call REST service(POST) in JS using fetch API.

We are planning to change Authentication mechanism as Basic Auth. What is the most secured way of calling REST services from Java Script and how to do it ? Which authentication mechanism should I use to call service in JS?

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