Interesting subject. This is worth detailed modeling.
But why does this need a separate blockchain ... ?
It can be done on Steem with a new front end, control codes in posts, and accounts that follow other accounts.
E.g., unless A, B, C is following you, which follows an institutional verification procedure, your reports, offers, transactions do not appear on the front end. The institutional side can simply follow and unfollow participants. Only those followed by the correct account and using the write control code which is sniffed can perform specific actions.
Vote 300: As usual I'm late to the party.
It could probably be done on the public blockchain but it has heavy political implications (e.g. EC using STEEM) that are better addressed separately, ar a later stage, when people become more familiar with the technology.
My team is making a file system for Steem that allows private files. There are certain designs that allow this.
Probably there are many actual methods you guys can use to make a private section hosted on a public chain. In a way that can be justified and proven. I mean: to those in ministries.
Issue is that a blockchain for a small number of participants is just a database with signed entries and eventually somebody will ask that question while the idea is being pitched. And then, if any real interest materializes, the final result will be a standard database, while the blockchain part will be dumped. Most govts already use key files to registered entities for access and posting to common databases. They just require java. (Usually outdated version of java ... :P )
Actually this has been asked no later than today :-)
There are two aspects, one formal and one more fundamental:
But if this project hasn't budged yet (it should have been out in 2017) is because of lack of political consensus around "against payment": some private actors want to extract payment for data which is public and should be free; the Commission was considering forcing them through legislation to surrender that data for free; the blockchain offers the magic solution of "writing in a ledger" the value transfer and create a magic triangle: actors accessing the data pay with the blockchain token which they could have received from the Commission for free (so data access is free as the Commission wants); the private actors accumulate the token and come to the Commission to exchange it for euros (so they get real euros for the data as they want); Commission acts as a kind of internal exchange for the token of this blockchain; and all this comes out of the box when using a blockchain - if you had to use a database with signed entries that also implements a ledger you'd end up ... redeveloping a blockchain ...
The lingering question is "where do the euros come from" but then I'm just the IT guy, I proposed the solution and FISMA seemed happy. They'll need to come up with the answer to that but anyway, the good thing is that by recording a "debt", it "cuts the problem in smaller bits" - gives time to negotiate further how and at what rate those tokens are going to be exchanged ...