Chun-Feng Liao

Multicast‐based service discovery protocols such as mDNS/DNS‐SD are widely used in IoT environments. However, in heterogeneous IoT deployments, a large fraction of incoming discovery queries do not correspond to any services provided by a given device, resulting in substantial packet‐processing overhead despite producing no useful outcomes. This inefficiency is problematic for resource‐constrained IoT devices. Based on the observation that the distinction between query‐hit and query‐miss packets can be determined using only a compact, query‐oriented view of service state, we propose an in‐kernel early filtering approach that projects service state into kernel space and performs early service matching in kernel. The proposed approach is realized using a Service State Projector and an Early Filtering Module implemented on eBPF and XDP. Experimental results show that, at a 95% query miss rate, throughput increases to over three times that of the baseline, while sustaining nearly 100% service responsiveness and maintains low order‐matched response lag. It also reduces total CPU utilization from over 20% to approximately 7% under a 500‐QPS workload, and reduces the number of system calls by more than 62.5%. Even when no filtering benefit can be realized, the additional processing cost remains limited, with only a 1.27% increase in total CPU utilization under saturated load and less than a 1% reduction in throughput.

Dependency Injection (DI) is a widely adopted design pattern in the software industry. DI reduces the otherwise necessary coupling between a client and the concrete object providing the service. This decoupling is achieved by delegating the responsibility of object creation to an external DI module, commonly referred to as a DI Container. Nevertheless, DI can introduce certain side effects. To guide the external DI module on the wiring logic, developers must either detail these logics in configuration files or use language constructs specific to the DI implementation in use. In large-scale projects, managing these wiring logics can pose a significant challenge to software maintainability. Currently, the Spring Framework stands as one of the most prominent DI implementations. It provides three methods for describing the wiring logic: XML, Annotation, and Java Class. This paper delves into the effects of these three methods on software maintainability, their influence on software design, and the optimal circumstances for each method’s use in managing wiring logic. Our study examines the issues aforementioned using the well-known web application benchmark, JPetStore. We adapt the benchmark application’s source code through different wiring logic implementations and evaluate the resultant effects on software coupling metrics. Finally, we explore the implications of these modifications on software coupling and maintainability.

The advent of the smart home, fueled by the rapid emergence of tiny embedded IoT devices and sensors, brings the consideration of space and location information to the forefront of service discovery. In a smart home environment, spaces often have composite capabilities and complex structures. Since residents may have varying preferences based on their location within different spaces, traditional service discovery results may be suboptimal without considering the spatial context. This paper introduces a seamless approach to integrate space and location information with mDNS/DNS-SD, a widely utilized service discovery protocol in home networks. We provide a formal specification for this approach, develop a prototype, and perform a series of experiments to evaluate the efficacy and potential of the proposed method.

A Pervasive-computing-enriched smart home environment, which contains many embedded and tiny intelligent devices and sensors coordinated by service management mechanisms, is capable of anticipating intentions of occupants and providing appropriate services accordingly. Although there are a wealth of research achievements in recent years, the degree of market acceptance is still low. The main reason is that most of the devices and services in such environments depend on particular platform or technology, making it hard to develop an application by composing the devices or services. Meanwhile, the concept of Web of Things (WoT) is becoming popular recently. Based on WoT, the developers can build applications based on popular web tools or technologies. Consequently, the objective of this paper is to propose a set of novel WoT-driven plug-and-play service management schemes for a smart home called Resource-Oriented Service Administration (ROSA). We have implemented an application prototype, and experiments are performed to show the effectiveness of the proposed approach. The results of this research can be a foundation for realizing the vision of “end user programmable smart environments”.

We can perceive the advent of smart living spaces attributed to the fast emerging of IoT (Internet of Things) technologies. By combining with the blockchain technology, many innovative business models can be brought into reality. This paper aims to report our recent progress in investigating the architectural issues for realizing blockchain-driven IoT services. In particular, we present and discuss four typical architectural styles for such services. A preliminary evaluation against different styles is also provided to compare the given styles.