Exactly, it should be like an API token or a signed blob, that allows the ID owner X (the student) to ask the verifier V (part of Govt) to verify ID for query e

Exactly, it should be like an API token or a signed blob, that allows the ID owner X (the student) to ask the verifier V (part of Govt) to verify ID for query entity Q. This string can be checked by those holding the private key for Q. X:Q = V->generatepair(Qpub) // Generate a unique ID stri g for interacting with the university. Not confidential, because not verifiable by anyone. Tok = V->encode(Xpriv, X:Q, Qpub, property:FullName, Vpriv) // Generate a token string unique to the pairing of X:Q, for a specified property like FullName, signed by the verifier. FullName = decode(Tok, Xpub, Qpriv) // The query entity (university) can decide this blob, but no one else can. If the Q looses confidentiality of Qpriv and all the Tok, then that data is lost. But having that doesn't let the attacker prove they are X to a different entity. I'm sure more rigorous schemes have been thought out, but there is so much inertia in changing anything.