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The IdP provides a number of general-purpose storage facilities that can be used by core subsystems like session management and consent. Broadly speaking, there are two kinds of storage plugins: client-side and server-side. Client-side plugins have the advantage of requiring no additional software or configuration and make clustering very robust and simple, but they only support a subset of use cases. Server-side plugins (aside from the simple case of storing data in memory) support all use cases, but require additional software and configuration, and usually create additional points of failure in a clustered deployment.
You may wish to review the SameSite topic, as it may have implications for your storage options and/or the need to address SameSite based on your chosen options.
The IdP ships with 3 preconfigured org.opensaml.storage.StorageService beans:
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