IdP == Identity Provider. A thing that knows what accounts exist, and how to authenticate for them. Contrast: RP (relying party), which needs the IdP to identify who someone is.
Your IdP can be, like, GSuite auth. RP can be any app that believes GSuite when it makes assertions about who you are, via OpenID Connect or SAML.
I found "Intrusion Detection and Prevention System" but I don't think that's it.