OAuth 2.0 Flows: Which support a refresh token?

Which OAuth 2.0 flows support a refresh token?

a) Authorization Code Flow, Implicit Flow
b) Authorization Code Flow, Resource Owner Password Credentials Flow
c) Client Credentials Flow, Implicit Flow
d) Resource Owner Password Credentials Flow, Client Credentials Flow

Answer:

In OAuth 2.0, the Authorization Code Flow and the Resource Owner Password Credentials Flow are the two flows that support a refresh token.

Within the context of OAuth 2.0, flows that support a refresh token are the Authorization Code Flow and the Resource Owner Password Credentials Flow. These two flows provide a mechanism for obtaining a new access token when the current one expires, without requiring the user to re-authenticate, thanks to the use of the refresh token.

The Authorization Code Flow involves multiple steps for token retrieval. Initially, the application sends the user to the authorization server. Once the user grants access, the server redirects the user back to the application with an authorization code. The application then exchanges this code for an access token and a refresh token.

On the other hand, the Resource Owner Password Credentials Flow allows the client application to directly present the user's credentials to the authorization server in order to receive an access token and a refresh token. This flow is typically used in scenarios where the client application is highly trusted.

Both flows ensure that the user can continue to access resources securely without disruptions due to expiring access tokens. They offer a convenient way to maintain access without requiring the user to constantly log in again, providing a better user experience.