JLINC Protocol
JLINC is an open protocol for sharing data protected by an agreement on the terms under which the data is being shared.
The agreement is known as an Information Sharing Agreement, and can be a reference to a standardized agreement (a Standard Information Sharing Agreement or SISA) or a one-off specialized contract.
The base profile is HTTP-based, but any protocol that affords methods for initiating and responding to data transactions, along with metadata (headers) accompanying those interactions could be adapted.