本研究設計且實作一個具象狀態傳輸智能物聯網中介層軟體(IoT Middleware)，命名為ACAN。物聯網中介層軟體是介於作業系統以及應用程式之間的軟體，專門用來解決異質性設備和服務應用的橋樑，並提供使用者更多的系統服務。 ACAN的設計目標有裝置管理、互操作性、平台可攜性、情境感知、資料紀錄、安全性與隱密性。裝置管理可以讓使用者對智慧物件進行註冊及權限的管理；互操作性可以讓使用訊息序列遙測傳輸(Message Queuing Telemetry Transport, MQTT)協定以及受限制的應用協定(Constrained Application Protocol, CoAP)的設備都可以進行通訊；平台可攜性可以讓支援Python程式語言的Linux平台，都可以安裝ACAN並正常運作；情境感知讓使用者發送的Restful指令可以透過ACAN自動選擇MQTT以及CoAP；資料紀錄可以讓使用者保存特定數量的歷史資料；安全性主要是利用安全通訊協定(Secure Sockets Layer, SSL)對封包進行加密，來防止封包資料被竊取；隱密性利用存取控制對使用者進行保密的動作，在沒有權限的情況下是無法對物件進行存取與操控。本研究在Intel i7 個人電腦上實作ACAN中介軟體，並架設一個網站提供使用者創建帳戶以及對智慧物件進行註冊與權限管理。另外，並且利用樹莓派(Raspberry Pi)開發板加裝溫溼度感測器和發光二極體(Light-Emitting Diode, LED)做為智慧物件來驗證ACAN實作已達成所有設計目標。

This study proposes the design and implementation of a RESTful Smart IoT middleware, named ACAN. IoT middleware is a software between the operation system and the application； it can be used to bridge heterogeneous devices and applications, and can provide users with more system services. ANCA has the following design goals: device management, interoperability, platform portability, context awareness, data logging, and security/privacy. The “device management” goal is to allow users to register for smart objects and control their access. The “interoperability” goal is to make devices using the Message Queuing Telemetry Transport (MQTT) protocol and the Constrained Application Protocol (CoAP) communicate with the middleware. The goal of “platform portability” is to allow ACAN to run on any Linux-like platform supporting the Python language. The goal of “context awareness” is to allow ACAN to automatically select between MQTT and CoAP when receiving RESTful commands from users. The goal of “data logging” is to allow users to keep a certain number of historical data. The goal of “security” is to use the Secure Sockets Layer (SSL) to encrypt packets for preventing data theft. The goal of “privacy” is to incorporate proper access control to prevent data from unauthorized accesses. This study also implements ACAN design on an Intel i7 PC, and sets up a website for creating user accounts for smart object registration and access control management. In addition, the study also realizes some smart objects by using Raspberry Pi boards equipped with temperature sensors, humidity sensors, and light-emitting diodes to verify if the ACAN implementation reaches all design goals.

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