The exponential growth of the Internet of Things (IoT) ecosystem has amplified concerns regarding device reliability, interoperability, and security assurance. Despite the proliferation of IoT security guidelines, a unified and quantitative approach to measuring trust remains absent. This paper introduces SCI-IoT (Secure Certification Index for IoT), a standardized and quantitative framework for trust scoring, evaluation, and certification of IoT devices. The framework employs a six-tier grading model (Grades A-F), enabling device profiling across consumer, industrial, and critical infrastructure domains. Within this model, 30 distinct Trust Tests assess devices across dimensions such as authentication, encryption, data integrity, resilience, and firmware security. Each test is assigned a criticality-based weight (1.0-2.0) and a performance rating (1-4), converted to a normalized percentage and aggregated through a weighted computation to yield the Secure Certification Index (SCI). The SCI determines the device's Trust Verdict, categorized into five SCI levels, and serves as the foundation for optional grade-based certification. The framework also incorporates critical gate conditions, enforcing absolute compliance in high risk parameters to prevent certification of devices with fundamental vulnerabilities. By unifying quantitative trust scoring with structured certification criteria, SCI-IoT provides a transparent, scalable, and reproducible method to benchmark IoT device trustworthiness. The proposed system aims to streamline manufacturer compliance, improve consumer confidence, and facilitate global interoperability in IoT security certification.

翻译：物联网（IoT）生态系统的指数级增长加剧了人们对设备可靠性、互操作性和安全保障的担忧。尽管物联网安全指南不断涌现，但衡量信任的统一定量方法仍然缺失。本文提出SCI-IoT（物联网安全认证指数），这是一种用于物联网设备信任评分、评估与认证的标准化定量框架。该框架采用六层分级模型（A-F级），支持对消费级、工业级和关键基础设施领域的设备进行画像分析。在此模型中，30项独立的信任测试从身份验证、加密、数据完整性、抗扰性和固件安全等维度评估设备。每项测试均分配基于关键性的权重（1.0-2.0）和性能评级（1-4），通过归一化百分比转换后，经加权计算聚合生成安全认证指数（SCI）。SCI决定设备的信任判定结果，归入五个SCI等级，并作为可选分级认证的基础。该框架还纳入关键门槛条件，强制要求高风险参数绝对合规，以防止存在根本性漏洞的设备获得认证。通过将定量信任评分与结构化认证标准相统一，SCI-IoT提供了一种透明、可扩展且可复现的方法来基准化物联网设备的可信度。所提出的系统旨在简化制造商合规流程，提升消费者信心，并促进物联网安全认证的全球互操作性。