The most confusing aspect of the SP software for beginners, aside from all the SAML and federation concepts, is how the software relates to the applications and resources it's being used to protect. Early use tends to lead to a lot of common questions:
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Logical and Physical SPs
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A single installation of the SP software can act as many logical, distinct "services", and a single logical "service" can span any number of physical hosts. |
The first point to make is that the term "Service Provider" (SP) gets thrown around a lot in the documentation and in email, and sometimes it means slightly different things based on context. Like a lot of things in computing, there's the physical part (the software bits you're installing) and the logical part (the notion of a service).
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The meat of the software configuration is divided across two sections of the shibboleth3shibboleth2.xml file: the <RequestMapper> and the <ApplicationDefaults> elements. In the case of Apache, the former is generally omitted in favor of Apache-specific commands.
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Once you assign a non-default applicationId property to some set of content, you have to complete the configuration by defining an "application override" in the shibboleth3shibboleth2.xml file. Defining a new application requires the minimum of an <ApplicationOverride> element just inside the closing </ApplicationDefaults> tag. An id attribute is needed with the applicationId used in the resource mapping step above. The rest depends on what's intended to be different about the application from the default settings.
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