Computer-networks

What I needed to develop:

Design and implement a green pass management service according to the following specifications. A user, once vaccinated, through a client connects to a vaccine center and communicates the code of his health card. The vaccine center communicates to ServerV the code received by the client and the validity period a of the green pass. A client, to verify if a green pass is valid, sends the code of a health card to the ServerG which requires the ServerV to check the validity`a. A ClientT can also invalidate or restore the validity of a green pass by informing the ServerG of a person’s infection or recovery through the health card code.