## 3 Materials and Methods
### Materials
#### 3.1.1 IOTA Identity  
The IOTA Identity framework is built in accordance with the W3C standards for decentralized identity management, ensuring seamless interoperability between different systems and stakeholders. This is a critical feature because it allows different parties, such as issuers, holders, and verifiers, to interact with the system without the need for a centralized intermediary. The framework facilitates several essential operations, including the identity registration, issuance and validation of Verifiable Credentials (VCs), and a robust credential revocation mechanism. By integrating the principles of Decentralized Identity (DID) and Self-Sovereign Identity (SSI), it empowers users to take full control of their digital identity.  
The main components of the IOTA Identity Framework enable users to create unique and secure digital identities that are stored in a distributed ledger. The system leverages IOTA's Tangle technology to ensure data integrity, security and scalability. The use of Verifiable Credentials enables the trusted sharing of identity information while maintaining privacy and minimizing reliance on centralized authorities. Verifiable Presentations enable users to present credentials in a secure and privacy-preserving manner, ensuring that only relevant information is shared when needed.  
A key feature of the IOTA Identity Framework is its support for revocation mechanisms that allow the status of credentials to be updated or revoked in real time. This is critical for maintaining the trustworthiness of credentials, especially in dynamic environments where data may change or become invalid. In addition, the framework uses cryptographic proofs and the inherent security of the IOTA network to ensure that identity information is tamper-proof and cannot be altered without the appropriate permissions.  
IOTA Identity framework is compounded with the following characteristics that follow the actual standards and other ones that belong to the network of IOTA:* IOTA DID Method: The IOTA DID standard follows W3C specifications and outlines how to manage DID documents stored on the IOTA Tangle. The DID is composed of two parts: \"did:iota:\" and \"iota-specific-idstring\". The \"iota-specific-idstring\" is further divided into two components: \"iota-network\", which identifies the specific IOTA network, and \"iota-tag\", an alphanumeric string of 44 characters that uniquely identifies the entity within the IOTA network. The \"iota-network\" part is up to 6 characters long, representing the specific IOTA network in use.
* Revocation Bitmap: This is a credential revocation mechanism that disables the cryptographic keys associated with a verification method, making it invalid for generating new digital signature proofs. Once revoked, the credential becomes invalid, and any verifier can check its revocation status by querying the verifiable data registry, such as the IOTA Tangle.
* Verification Methods: These are parameters used in conjunction with a process or protocol to independently verify a proof. For instance, a public key can be used to verify a digital signature, ensuring that the signer possesses the associated private key.
* Verification Relationships: It defines the relationship between a DID subject and a verification method. The W3C outlines several useful verification relationships that can be included in a DID Document (DDo), such as authentication, assertion, key exchange, invocation capability, and delegation capability.