Quote from: laiwendersky on December 16, 2017, 02:07:23 PM

on your website, the description about 'Privacy and Access Control', I have some question: can the block chain be modified? how do you do it? how to guarantee the privacy of the data?

"Medicalchain provides the user full access and control of their data and how this data is shared. The user will have the functionality of providing different access levels to different users; they would assign a set of access permissions and designate who can query and write data to their blockchain."

We are building on Hyperledger Fabric, this is a permissioned blockchain solution that accommodates for this specific use-case.
We can guarantee the immutability of the data, while retaining the confidentiality, which is paramount with such sensitive data.

The blockchain works as the guarantee that the data held within the system is immutable, that access to that data is strictly controlled and can be moderated by the owner of that data.
In Hyperledger Fabric, "chaincode" is the 'smart contract' that runs on the peers and creates transactions.
Users on the platform can create transactions (from our application) on the network's shared ledger, which then updates the global state of the assets.

Hyperledger have their own explainer as to how this works on a general level, but this example is not exactly the same as what we are building:
https://youtu.be/EKa5Gh9whgU
We will be releasing our own explainer in the new year as to how our platform works in more detail.