近年來，物聯網裝置與技術逐年成長，而其目前的困境是既有的程式通常採用單體式架構，面對日趨龐大且複雜的程式，在功能性擴充或是效能擴充上較難有應變彈性，若能使用微服務架構取代既有單體式架構問題便能迎刃而解。而微服務主要是將既有程式切割成多個完全獨立的模組，並且透過 HTTP 等網路協定當作跨模組的溝通協定。
本論文針對物聯網設計一微服務架構之平台，以微服務作為最小粒度，並且使用既有的開源專案 Docker 作為部署工具，有別於以雲端為主的平台，本論文成果將部署在邊緣裝置上以解決雲端服務在延遲較嚴重的情況，並搭配容器等技術使微服務得到更完整的效能彈性。在規範上，以全球資訊網協會制定的 WoT 規範為基礎，制定以服務為最小粒度的規範，服務為微服務架構中定義之最小可獨立運作之模組，WoT 為全球資訊網協會協同多間網路服務商制定之規範，目的在於提供統一的規範以利跨廠商間的裝置協同運作。
本論文實作以微服務架構設計為基礎，將微服務架構之物聯網專案部署在多個邊緣運算裝置上。實作內容包含：(1)以微服務架構設計之物聯網專案，提供更好的功能擴充彈性；(2)使用 mDNS 協定提供服務的可發現性，提供在同一網域下自動發現服務，提供相較傳統物聯網上更便利的可發現性；(3)實作符合服務描述規範之服務，內容如種類、描述、通訊介面等。
本論文旨在將微服務架構導入物聯網，並且根據 WoT 規範制定最小粒度為服務的框架，提供彈性更好、擴展容易的程式架構；在部署上，採用邊緣運算和 Docker 工具，用以解決雲端運算的既有延遲嚴重等問題。

Applications of Internet of Things (IoT) increase rapidly and can be observed almost everywhere. However, during the widespread growing, many issues from different arenas have emerged which range from the development of IoT applications to the deployment of IoT devices provided by different makers. Interoperability is the most noticeable one among these issues and it is considered as the main source of causing the fragmentation. Scalability and findability are the other two important issues in developing sophisticated IoT applications. In addressing these issues and taking advantage of existing Web technology, WoT (Web of Things) has been proposed as one general approach. A WoT platform which integrates useful techniques to help manage IoT devices as well as build IoT applications would be very beneficial.
This study aims to build a WoT platform which would help improve the efficiency in building IoT applications and increase the interoperability, scalability and findability of using IoT devices. The platform is designed based on the concept of microservice architecture and take advantage of edge computing. A microservice can either be provided by the function of an IoT device standing as a node supporting edge computing or implemented by a software module working in the server-client style. By composing the functionality of an IoT application through combining stand-alone microservices as much as possible, the conventional monolithic application program can be divided into a number of microservices among which there are basic core microservices taking charge of necessary management functions and optionally configured microservices, either local or remote ones, responsible for carrying out the functions required by the application. The architecture thus helps decrease the coupling while increasing the scalability. To counter the fragmentation issue in IoT application, the WoT recommendations proposed by World Wide Web Consortium (W3C) is followed to increase the interoperability. To increase the findability, multicast domain name service (mDNS) protocol is used to help find the desired services. In concerning the performance and to reduce consuming network bandwidth, the mechanism of service chain is included in the design.
An example implementation is conducted to demonstrative the effectiveness of the WoT platform. The example microservices were implemented and deployed using container technology on the edge computing service, and classic HTTP protocol is used for communication. The results of running test cases showed that the example WoT platform worked well and the microservices provided by IoT devices could be easily configured into the application. This study therefore concludes that microservice architecture can be applied to build WoT platform and effectively helps develop IoT application.

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