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http://wayf.incommonfederation.org/InCommon/InCommon-metadata.xml
Policy
InCommon expects participants to refresh metadata daily to ensure that SAML endpoints have access to the most up-to-date keys and other registered information. Some software implementations (such as Shibboleth) handle metadata easily, but regardless of your software, please read this entire page to understand the requirements and pitfalls associated with metadata consumption.
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In addition, if you don't refresh your metadata regularly, it is likely that a software implementation will fail at some point since the XML document carries an expiration date (validUntil) that causes the metadata to expire in two weeks. InCommon strongly recommends that you do not rely on the actual length of this validity interval in any way, and in fact, we reserve the right to shorten the validity interval with little or no notice.
Metadata Refresh
Signature Verification
Federation metadata is signed for integrity and authenticity. Participants are strongly encouraged to verify the XML signature on the metadata file before use; failure to do so will seriously compromise the security of your SAML deployment.
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For convenience, we provide a set of (suitably modified) schema files that permit offline schema validation.
Expiry Verification
Federation metadata has an expiration date, much like an X.509 certificate. It is important that expired metadata not be accepted, otherwise an attacker would be able to substitute expired metadata in conjunction with a metadata refresh. In particular, a metadata file should not be accepted if either of the following conditions are true:
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| Warning | ||
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Verifying the signature on a SAML metadata file does not verify the presence or value of an expiration date. The only way to verify the expiration date is to parse the XML. |
Configuration
Firewall Configuration
Depending on your environment, you may have to poke a hole in an outbound firewall to allow your metadata client to reach the metadata server. In that case, you will actually want to poke two holes in that firewall since there are two metadata servers as described below.
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