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The evolution of mobile networks toward ubiquitous connectivity envisioned by International Mobile Telecommunications-2030 has caused a surge in control plane traffic. A deep understanding of the control plane’s internal characteristics and mechanisms is crucial for delivering optimal services. However, existing measurements often neglect the control plane or treat it as an opaque box, focusing on overall performance instead of its intrinsic characteristics. In this paper, we introduce a 3GPP-compliant control plane evaluation framework and conduct the first in-depth analysis of the characteristics and overheads exhibited by various network functions (NFs) under large-scale connectivity conditions, based on empirical measurements. We selected three core network systems and conducted performance measurements on 500,000 User Equipment during UE registration and PDU session establishment procedures. We reveal the substantial resource demands and limited scalability of the Access and Mobility Management Function (AMF) and the Network Repository Function (NRF). Furthermore, our analysis identifies a significant need for an enhanced state management mechanism. The insights derived from our measurements underscore the immense potential for optimization within the core network. Key optimization pathways include enhancing protocol stack processing, mitigating potential leverage-based attacks, and implementing an integrated state management framework. 

Abstract Fluorophores with high quantum yields, extended maximum emission wavelengths, and long photoluminescence (PL) lifetimes are still lacking for sensing and imaging applications in the second near‐infrared window (NIR‐II). In this work, a series of rod‐shaped icosahedral nanoclusters with bright NIR‐II PL, quantum yields up to≈8%, and a peak emission wavelength of 1520 nm are reported. It is found that the bright NIR‐II emission arises from a previously ignored state with near‐zero oscillator strength in the ground‐state geometry and the central Au atom in the nanoclusters suppresses the non‐radiative transitions and enhances the overall PL efficiency. In addition, a framework is developed to analyze and relate the underlying transitions for the absorptions and the NIR‐II emissions in the Au nanoclusters based on the experimentally defined absorption coefficient. Overall, this work not only shows good performance of the rod‐shaped icosahedral series of Au nanoclusters as NIR‐II fluorophores, but also unravels the fundamental electronic transitions and atomic‐level structure‐property relations for the enhancement of the NIR‐II PL in gold nanoclusters. The framework developed here also provides a simple method to analyze the underlying electronic transitions in metal nanoclusters.