MQTT over QUIC protocol has recently garnered attention in the IoT field. This protocol enables faster communication than the traditional MQTT. However, the security risks arising from the new combination of MQTT and QUIC still need to be explained. In particular, the MQTT over QUIC broker's availability could be compromised by initial attacks that exploit specific vulnerabilities of the QUIC protocol. Initial attacks target the handshake process of the QUIC protocol and unfairly consume server-side resources. This study examines the impact of initial attacks on MQTT over QUIC brokers and proposes defensive measures. Our verification shows that initial attacks can indeed compromise the availability of MQTT over QUIC brokers. Furthermore, we confirmed that maintaining session continuity can preserve broker availability against initial attacks.

Cloud-Edge Continuum Computing Platform hosts real-time applications over edge and cloud resources. The execution time of real-time applications composed of micro-services is increased by the communication latency, which is the time between a packet entering and leaving the network. To keep the execution time small, a latency-guaranteed network, which determines an upper bound of the latency, will be effective. Motivated by this requirement, we have been enhancing Deterministic Networking (DetNet), a protocol suite that builds a latency-guaranteed network over Wide-Area Networks (WAN).

In incineration plants, indoor positioning systems are needed to prevent workers from approaching hazardous areas and to facilitate rescue operations in emergencies. Although many positioning systems using signal strength indicators such as Wi-Fi Received Signal Strength Indicator (RSSI) have been proposed, the vast interior of incineration plants increases the cost of constructing a communication infrastructure using $\mathbf{5 G H z}$ Wi-Fi. Therefore, by adopting Low Power Wide Area (LPWA), which allows for long-distance communication, the number of Access points (APs) that need to be installed in the environment can be reduced, thus lowering the cost of constructing the communication infrastructure. IEEE 802.11ah (11ah) is a new LPWA standard that uses the Sub-GHz band. In this study, we deployed new 11ah receivers in an incineration plant where IEEE 802.11ac (11ac) is already established and evaluated their coverage and area classification performance. The experiment demonstrated that the entire incineration plant can be covered with fewer units compared to 11ac. Additionally, when a small number of 11 ah receivers were installed, the system identified individual rooms with higher accuracy than 11ac, suggesting that 11ah RSSI is a promising feature that can be obtained at low cost.

There are broad benefits to developing pedestrian spaces in terms of environment, culture, and economy. Given this context, accurately measuring pedestrian traffic is considered a critical indicator of sidewalk usage. Currently, the mainstream method for detecting pedestrians utilizes RGB camera footage installed along sidewalks. However, especially during nighttime and adverse weather conditions, insufficient lighting hampers detection accuracy. In contrast, Far-Infrared(FIR) imaging does not require a light source as it measures radiated heat. This study proposes a pedestrian detection and tracking model that integrates the strengths of both RGB and FIR cameras through image fusion processing. Specifically, pedestrians are detected from fused images using a pedestrian detector and then tracked using a tracking system to measure pedestrian counts. Additionally, a version of the pedestrian detector trained on the fused images through transfer learning is developed, and its detection results are compared with those from a non-transfer learning model. The experimental results demonstrate that using fused images for detection and tracking is effective in specific data scenarios, confirming the utility of the image fusion model under varied conditions.

Cloud bursting functionality provides the administrators of on-premise supercomputing systems with an on-demand way of dynamically integrating the computing resources on the cloud into them when the computing demands from the users dramatically increase. In the Cybermedia Center at Osaka University, we have deployed a cloud bursting environment between a supercomputing system named SQUID and Microsoft Azure by respecting the transparency in usage rather than performance. Technically, the transparency allows users to execute their jobs on the cloud computing resources without having to be aware of the cloud in terms of usage. However, how we encourage users of our supercomputing system to use the cloud computing resources is a realistic and important problem to be solved from a practical operational perspective. In this paper, we investigate the cloud bursting environment on SQUID in terms of performance, monetary cost, and transparency on usage. Finally, we discuss how we as the administrators of on-premise supercomputing systems can provide a better way to encourage users to execute their jobs on the cloud computing resource instead of on the on-premise computing resource under our service policy.