...
The SP includes http://id.incommon.org/assurance/silver in the SAML AuthnRequest element. It accepts assertions that contain http://id.incommon.org/assurance/silver in the AuthnContext from IdPs with http://id.incommon.org/assurance/silver in InCommon metadata, i.e.that is, the SP explicitly verifies that the assertion contains http://id.incommon.org/assurance/silver in the AuthnContext and that InCommon metadata contains http://id.incommon.org/assurance/silver for the issuing IdP.
...
- Assertions that contain http://id.incommon.org/assurance/silver in the AuthnContext from IdPs with http://id.incommon.org/assurance/silver in InCommon metadata, or
- Assertions that contain http://id.incommon.org/assurance/bronze in the AuthnContext from IdPs with http://id.incommon.org/assurance/bronze in InCommon metadata
...
- metadata
...
As usual, the SP should intelligently handle errors. In particular, the SP should be prepared to handle the case that not all users at a particular IdP may be eligible for Silver or Bronze LOA (for example, users not vetted at the Silver LOA or passwords too weak for Bronze LOA), so even if the IdP is tagged with http://id.incommon.org/assurance/silver or http://id.incommon.org/assurance/bronze in InCommon metadata, authentication for some users may result in a "FatalProfileException".
...