# Service Provider

### Definition

The Service Providers are standard applications that rely on Identity Providers to let the users log in.

#### Join federation

To join the federation, the service provider management team must deliver its "Metadata". The service provider Metadata describes how the service providers behave:

- Which security algorithms does it support.
- The public portion of its signing and encrypting keys.
- The SAML protocol does it support.
- The URL of each SAML protocol endpoint.
- Contact information.

### Standard attributes

<p class="callout info">To see more information about the service providers types and attributes, you can check the [Service providers](https://bookstack.soffid.com/books/soffid-4-reference-guide/page/service-providers-addon-federation "Service Providers (addon federation)") page.</p>