The upcoming 6G Non-Terrestrial Networks (NTN) technology is expected to enable comprehensive connectivity of the Internet of Things (IoT) across various environments. The presence of a large number of IoT devices operating in diverse scenarios, along with the associated vast amounts of data, poses challenges in terms of security and privacy for the 6G NTN IoT networks. Therefore, blockchain technology is considered a key solution for enhancing network security and simplifying management in 6G networks. While IoT devices usually adopt heterogeneous blockchain platforms in different scenarios, cross-chain identity authentication technology is a prerequisite for secure interactions. However, traditional authentication techniques, such as PKI-based solutions, face challenges in handling authentication within 6G Non-Terrestrial Networks, since techniques heavily rely on trusted third-party certificate authorities (CAs) to issue credentials across blockchains. In response to these challenges, we propose a decentralized cross-chain identity authentication scheme for 6G NTN IoT networks called IoTAuth. We design a novel authentication mechanism with user autonomy, combining threshold signatures and DID technology to transform the process of identity credential issuance into a collaborative issuance by multiple nodes under the 6G NTN IoT networks. Furthermore, the scheme realizes cross-chain identity authentication without a centralized manner via an identity conversion mechanism based on relay-chain technology, which further guarantees security in the 6G NTN IoT networks context. The experimental results illustrate the effectiveness and practicality of the scheme. Finally, we present comprehensive future directions.

中文翻译：

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IoTAuth：6G非地面物联网网络的去中心化跨链身份认证方案


即将推出的 6G 非地面网络 (NTN) 技术预计将实现跨各种环境的物联网 (IoT) 的全面连接。大量物联网设备在不同场景下运行，以及相关的大量数据，给 6G NTN 物联网网络的安全和隐私带来了挑战。因此，区块链技术被认为是6G网络中增强网络安全、简化管理的关键解决方案。虽然物联网设备在不同场景下通常采用异构区块链平台，但跨链身份认证技术是安全交互的前提。然而，传统的身份验证技术（例如基于 PKI 的解决方案）在处理 6G 非地面网络内的身份验证方面面临挑战，因为该技术严重依赖受信任的第三方证书颁发机构 (CA) 来跨区块链颁发凭证。针对这些挑战，我们提出了一种用于 6G NTN 物联网网络的去中心化跨链身份认证方案，称为 IoTAuth。我们设计了一种新颖的用户自主身份验证机制，结合门限签名和DID技术，将身份凭证颁发过程转变为6G NTN物联网网络下多个节点的协作颁发。此外，该方案通过基于中继链技术的身份转换机制，实现了无需中心化方式的跨链身份认证，进一步保证了6G NTN物联网网络环境下的安全性。实验结果验证了该方案的有效性和实用性。最后，我们提出了全面的未来方向。