## 1 Introduction
This approach enables the creation of identities independently of governments, corporations, or global organizations [6]. The World Wide Web Consortium (W3C), an international body dedicated to developing web standards, has defined two fundamental standards for a secure and privacy-preserving decentralized identity architecture: DIDs and VCs both utilize asymmetric cryptography to ensure the privacy, integrity, and authenticity of identity-related information. DIDs are generated using cryptographic key pairs, where a public key encrypts messages sent to the identity and a private key decrypts them, proving ownership and control. VCs rely on similar cryptographic principles, with the issuing entity digitally signing credentials using its private key. These credentials can then be verified using the public keys of the issuer and the recipient, ensuring that the credentials are authentic and unaltered. Together, DIDs and VCs provide a secure and flexible system for decentralized identity management, enabling trusted interactions in IoT ecosystems. Despite its potential, adopting decentralized identity management in IoT ecosystems using IOTA presents several challenges. The high computational demands of cryptographic operations on resource-constrained devices, such as IoT sensors or Raspberry Pi, remain a critical issue. Interoperability with existing identity frameworks, such as Hyperledger Indy and Ethereum, is another barrier, requiring the development of bridging solutions. Additionally, the lack of standardized communication protocols like DIDComm in the IOTA framework limits seamless interactions between decentralized identities. The scalability of non-permanent nodes in the IOTA Tangle and their associated data persistence issues also pose challenges. Finally, ensuring regulatory compliance, such as adherence to the General Data Protection Regulation (GDPR) while leveraging decentralized identity principles, introduces complexities that must be addressed to ensure broader adoption and practical usability. This research builds upon a growing body of work on decentralized identity and IoT security. Recent studies emphasize the potential of blockchain and DAG-based systems, like IOTA, in mitigating IoT vulnerabilities and improving transparency, accountability, and user empowerment in decentralized environment principles; IOTA strengthens privacy-preserving and scalable identity management in IoT networks, addressing critical challenges in the decentralized Internet. This study proposes a decentralized identity management model that uses the IOTA framework to enable secure and scalable identity solutions for IoT devices. By incorporating SSI principles, the model empowers devices with verifiable, independent identities, ensuring data privacy and user control while mitigating the risks associated with centralized architectures. Specifically, the study focuses on integrating IOTA Identity for Decentralized Identifiers, IOTA Streams for secure data exchange, and IOTA Stronghold for cryptographic key management. The primary objectives of our approach are as follows:  
1. To design and implement a proof-of-concept decentralized identity management system for IoT devices using IOTA. 2. To evaluate the performance, scalability, and security of the proposed system under resource-constrained IoT conditions. 3. To explore the broader implications of decentralized identity solutions for the future of IoT in the context of Web 3.0. This study addresses a critical gap in IoT identity management by proposing a scalable, secure, and privacy-preserving solution leveraging cutting-edge technologies such as the IOTA Tangle. The findings of this research have implications for advancing Web 3.0 paradigms and paving the way for a decentralized IoT ecosystem. This paper is organized as follows: Section 2 summarizes some related works; Section 3 describes the materials and methods employed in this study, including the hardware and software used, as well as the implementation details of the proposed framework.