Service Provider (SP)

In the context of Identity and Access Management (IAM)|identity and access management (IAM) and federated identity systems, a Service Provider (SP) is an entity or system that provides access to specific resources, services, or applications to authenticated and authorized users. The SP is one of the key components in a federated identity environment and relies on identity and authentication information provided by an Trusted Identity Provider (IdP)|Identity Provider (IdP) to make access control decisions.

The SP hosts or manages a set of resources, services, or applications that users want to access. These resources can include web applications, databases, APIs, files, or any other digital assets. The SP is responsible for controlling access to its resources. It relies on information received from the IdP to make access control decisions, such as determining which users are allowed to access specific resources and what level of access they have.

The SP establishes a trust relationship with one or more IdPs. This trust relationship allows the SP to trust the authentication and authorization information provided by the IdPs, enabling users to log in and access resources using their IdP-issued credentials.

The SP relies on the IdP to authenticate users. When a user attempts to access a resource protected by the SP, they are redirected to their IdP for authentication. Once authenticated, the IdP issues an authentication token or assertion, which the user presents to the SP to gain access.

Many SPs implement Single Sign-On (SSO) functionality, allowing users to log in once to access multiple resources hosted by the same or different SPs without the need to repeatedly enter credentials. The IdP may provide the SP with additional attributes or claims about the user, which can be used for authorization purposes. For example, the IdP might provide the user's role or group membership.

The SP must integrate with the federated identity system and implement protocols such as SAML (Security Assertion Markup Language)|Security Assertion Markup Language (SAML), OpenID Connect, or OAuth 2.0 to facilitate the exchange of authentication and authorization information with IdPs.

SPs typically maintain metadata that describes their endpoints, configuration details, and encryption keys. This metadata is often shared with IdPs to establish trust and enable secure communication. SPs need to implement appropriate security measures to protect against unauthorized access and data breaches. They must also handle authentication tokens and user data securely.

Examples of Service Providers include:

  • Web applications that require users to log in to access protected content.
  • APIs that provide access to specific functionalities or data.
  • Cloud service providers that host software-as-a-service (SaaS) applications.
  • Online retailers that offer personalized services and accounts.