In OAuth 2.0 the Client_id is unique for any OAuth Client on the same Authorization Server.

OAuth 2.0 Dynamic Client Registration Protocol allows clients to dynamically register using the registration_endpoint.

Client_id is a Public identifier for the Application.

Some Uses#

BY using Client_id / Client Secret you can potentially control which OAuth Clients are allowed to connect to your API and make decisions such as rate limit them or block them. This is the way that e.g. Twitter can ensure that no other twitter client is allowed to have over 100,000 users.

More Information#

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