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To solve security issues arising from multiple attackable vulnerabilities and key leakage in BACnet/IP authentication, a security-enhanced BACnet/IP-SA protocol authentication scheme was proposed.By analyzing the authentication message flow model of the protocol and modeling it using colored Petri net theory and CPN Tools, vulnerabilities in the security of BACnet/IP were identified.An improvement scheme was proposed based on the Dolev-Yao attacker model and formal analysis method.The BACnet/IP-SA protocol utilized the device’s pseudo-identity to safeguard the actual identity information.It emploied the PUF response for authentication and verified the authenticity of the counterparty’s identity.The session key was generated through the authentication value of the multi-information set.The protocol’s security was demonstrated by combining BAN logic and non-formal methods.The experimental results indicate that the proposed scheme can effectively resist security threats from multi-class attacks and key leakage, enhancing the security of the protocol authentication while reducing computational overhead.

Metallic glasses (MGs) are considered as promising materials for microelectromechanical systems (MEMS) due to their excellent mechanical properties combined with unique net shape formability. However, the prevalent fabrication of MG MEMS is based on semiconductor micro-manufacturing technology which is limited to 2D. This work introduces a mechanically guided manufacturing method which enables facile fabrication of free-standing 3D MG structures with predictable complex and high-aspect-ratio configuration. As examples, 3D MG architectures with out-of-plane aspect ratio up to three and MG microhelices arrays are fabricated. Most critically, we show the prepared architectures exhibit super-elasticity. Such unprecedented elasticity originates from the near-ideal elastic limit of MGs, combining with geometric optimization. Finally, we demonstrate that the microstructure of the MG 3D architectures can be tuned over a wide range, which is desirable in a wide range of applications such as sensing and energy harvesting devices.