The authorization server of the OAuth 2.0 implementation manages the authentication process in OAuth 2.0. Its main task is to issue OAuth 2.0 access tokens for the OAuth 2.0 client. The access tokens can be sent to the resource server.
SSL must be set up in the AS ABAP (see Parameters for OAuth 2.0 Administration).
The topic OAuth 2.0 Flows Supported by SAP illustrates the way an OAuth 2.0 client can get access to resources on an AS ABAP.