Comparison to Azure Websites Authentication about azure-activedirectory-library-for-js

[myusrn]

That azure web sites [aws] authN/authZ preview you reference above appears to be about enabling wsfed + session token cookies based federated identity [ / claims based ] security without you having to configure the required app settings in your aad tenant and enable the required web app owin katana security middleware module in your web app either using vs15/vs14 ide tooling support or manually.

I'm concluding this by looking at the resulting aad tenant settings I end up with after stepping through that azure mgmt. portal azure web site configuration option and then fiddler capturing the flows resulting from the default aws setup.

The adal for javascript story involves acquiring and using bearer tokens, through the use of oauth implicit grant flows, and using those to secure your web app service calls, i.e. attaching to authorization header.

There is a story for having a web app provide both wsfed -> openid connect [oidc] + session token cookies security and oauth bearer token security support which you'd be responsible for enabling. The post http://aka.ms/owinScBt discusses this.