Self-sovereign-identities (SSI) for IoT and next internet

1 . A computer-implemented system for at least one transaction comprising at least one smart contract between users of a network, comprising:

the network comprising a plurality of blockchains, each comprising at least one block linked by at least one cryptographic key each comprising a hash function and a timestamp to other blocks of the same blockchain, or one or more different blockchains, or both the same blockchain and one or more different blockchains, wherein

the network is accessible by the users, each user accessing the network through a corresponding computing device,

wherein the plurality of blockchains comprise:

private blockchains, wherein said each user owns at least one of said private blockchains and

public blockchains, wherein said each user owns or is associated to at least one of said public blockchains;

wherein the at least one smart contract comprises rules determining that upon execution of the at least one smart contract new blocks are added to at least one of the private blockchains and to at least one of the public blockchains of said each user involved in the at least one transaction, wherein the new blocks are linked by said at least one cryptographic key, wherein the computer-implemented system further comprises:

at least one digital identity associated to said each user, for authenticating said each user, said digital identity comprising a physical fingerprint;

at least one footprint blockchain for tracking all the transactions involving said each user, said at least one footprint blockchain comprising blocks of private blockchain(s) owned by said each user and blocks of public blockchain(s) linked to at least one private blockchain owned by said each user;

at least one digital repository, wherein the digital information, or a part of the digital information, of the at least one transaction is stored;

at least one trust function blockchain associated to said each user, being a public blockchain that records a set of parameters that define trust of said each user, on the basis of an algorithm whose rules are defined in the at least one smart contract;

wherein the at least one smart contract comprises rules determining that upon execution of the at least one smart contract new blocks are added to at least one footprint blockchain and to at least one trust function blockchain of said each user involved in the at least one transaction;

wherein the new blocks added upon execution of the at least one smart contract comprise a hyperlink towards the at least one digital repository where digital information of the transaction is stored.

2 . The computer-implemented system of claim 1 , wherein the parameters that define a user's trust are used as a proof-of-stake indicator in a blockchain protocol.

3 . The computer-implemented system of claim 1 , wherein the fingerprint associated to each user, comprises at least one physical unclonable function or a secure element.

4 . The computer-implemented system of claim 1 , wherein the plurality of private blockchains comprise a plurality of sidechains.

5 . A computer-implemented method for secure transactions between said users of a network, carried out by the computer-implemented system of claim 1 , comprising:

a) submitting a transaction between at least two users of the network, said transaction comprising at least one smart contract, said smart contract comprising rules;

b) authorizing the transaction;

c) executing the at least one smart contract;

and wherein the method comprises:

d) adding at least one new block to at least one blockchain of the computer-implemented system, on the basis of the rules defined in the smart contract; and

wherein said executing the at least one smart contract includes executing a consensus mechanism for addition of the at least one new block that is automatically granted on execution of the smart contract, wherein

the adding a new block to at least one blockchain consists of:

adding a new block to at least one private blockchain and to at least one trust function blockchain of each of said two or more users;

and wherein:

said b) authorizing the transaction comprises:

b1) authenticating the identity of the users involved in the transaction;

b2) verifying trust of the users involved in the transaction, by means of the trust function blockchain;

b3) authorizing the transaction in response to all users accepting and satisfying all the rules of the smart contract.

6 . The computer-implemented system of claim 1 , wherein the smart-contract comprises a plurality of independent rules-blocks, organized according to users' negotiation.

7 . The computer-implemented system of claim 6 , wherein said rules-blocks comprise links to a plurality of blockchains, or to a plurality of digital repositories, or to both a plurality of blockchains and a plurality of digital repositories, and wherein said rules-blocks are users of the network having a digital identity consisting in the pattern of said links.

8 . The computer-implemented method of claim 5 , wherein the rules comprise rules-blocks wherein acceptance of the rules-blocks by the users improves a level of trust of the rules-blocks of a given user.

9 . The computer-implemented method of claim 8 , wherein the consensus mechanism is deployed through the rules-blocks.

10 . The computer-implemented system of claim 1 , wherein at least one of the users is an object.

11 . The computer-implemented system of claim 4 , wherein at least two of the sidechains are semantically linked.

12 . The computer-implemented method of claim 5 , wherein said authenticating the identity of the users involved in the transaction is by fingerprint, by footprint, or by both fingerprint and footprint.

13 . The computer-implemented system of claim 1 , wherein the blocks in the computer-implemented system are linked by a first hash function to blocks of a first blockchain and by a second hash function to blocks of a second blockchain.

14 . The computer-implemented system of claim 1 , wherein the new blocks are also semantically linked.