[[alternative]]The design and implementation of smooth session migration in instant messaging through XMPP

碩士[[abstract]] 在行動裝置與無線網路普及的環境下，使用者得以在各種地方，利用各種裝置使用即時通訊系統。由於現行的即時通訊系統缺乏議程可移性(session mobility)，使得不同裝置上的即時通訊系統客戶端，無法存取相同的議程內容。本文探討即時通訊系統平順議程交遞(Smooth Session Migration, SSM)服務，使得轉換後的新裝置，能讀取轉換前舊裝置的議程內容。我們提出的SSM服務，是以server-based的方法，由伺服器端追蹤並儲存所有註冊SSM服務使用者的議程內容，當使用者於新裝置上線後，伺服器端再交遞所有議程內容到新裝置上。為了減低在議程交遞過程中，使用者遺漏訊息的機會，我們採用平順式的議程交遞：在使用者註冊後，議程交遞之前，伺服器端會阻斷其送出的離線在線狀態，使得使用者在變換裝置的空窗期間，仍然在其聯絡人處顯示為在線上，可正常收到訊息，就好像從未來離線過一樣。我們在客戶端有一個選擇性的外掛程式(Plugin)，以GUI介面以方便使用者啟動SSM服務，並幫助收集SSM服務啟動之前的訊息，我們採用XMPP為實作協定，實作SSM成為XMPP伺服器端的外掛程式，以增加伺服器端的功能。SSM系統可以追蹤並記錄議程內容中的一對一文字訊息。最後並以實驗說明SSM服務的效能，並將SSM服務與其它相似功能的系統，遠端桌面與離線訊息傳送作一比較。[[abstract]]The mobile device and wireless network is pervasive in our environment, and therefore the user can user any kinds of devices to communicate with others by the instant messaging system at anywhere. Since the current instant messaging system lacks of the session mobility, it caused the result that people cannot use the same session if they change the device. According to this requirement, we propose the smooth session migration(SSM) service. The SSM service allows the user using the previous session that they used before in other device. Our SSM service is a server-based approach. It means the server will trace and record all of the session contents that the registered SSM users have. Once they are online on the new device, the server then migrates all of his stored session contents to this device. In order to reduce the possibility of losing packets during the migration, we adapt the smooth session migration. When the user is offline temporarily, his unavailable presence packet will be intercepted by SSM, so his rosters don’t know he is already offline, and still send normally the instant message to him. There is an alternative client plugin, which has the GUI interface in order to facilitate users to activate the SSM, and also collects the former messages before SSM was started. We adapt the XMPP as our protocol, and implement the SSM as a plug-in of the XMPP server, in order to expand the functionality of the server. The session content that SSM traces and records is the one-to-one text message. We also take an experiment to examine the efficiency of SSM, and a comparison among the offline messages, remote desktop system and SSM.[[tableofcontents]]目錄 第1 章 緒論...............................................................................................1 1.1 研究背景與動機...........................................................................1 1.2 研究目的與方法...........................................................................3 1.3 論文架構.......................................................................................3 第2 章 相關研究......................................................................................5 2.1 網頁議程交遞系統.......................................................................6 2.1.1 使用者代理伺服器系統同時處理多項議程....................8 2.1.2 使用者代理伺服器系統的議程交遞協定........................9 2.2 行動即時通訊系統.....................................................................10 2.3 SIP 平順交遞機制.......................................................................11 第3 章 即時通訊系統............................................................................15 3.1 即時通訊系統簡介.....................................................................15 3.2 即時通訊系統歷史.....................................................................16 3.3 即時通訊系統架構.....................................................................16 3.4 Jabber 與 XMPP 協定...............................................................18 3.4.1 XMPP 的伺服器端與客戶端............................................20 3.4.2 路由規則...........................................................................20 3.4.3 JID (Jabber Identity) ..........................................................21 3.4.4 XMPP 協定的核心............................................................21 即時通訊平順議程交遞服務之設計與實作-以XMPP 為例 IV 3.4.5 XMPP 串流(Stream)..........................................................24 第4 章 SSM 服務...................................................................................26 4.1 劇本.............................................................................................26 4.2 SSM 服務設計.............................................................................28 4.3 使用者註冊.................................................................................30 4.4 在線狀態與訊息攔截器............................................................34 4.4.1 在線狀態攔截器...............................................................34 4.4.2 訊息攔截器.......................................................................37 4.5 SSM 元件.....................................................................................39 第5 章 SSM 實作...................................................................................47 第6 章 功能比較....................................................................................52 6.1 離線訊息傳送.............................................................................52 6.2 遠端桌面.....................................................................................52 6.3 SSM 和離線訊息傳送、遠端桌面功能比較............................53 第7 章 實驗.............................................................................................54 7.1 實驗設計.....................................................................................54 7.1.1 使用者個數情境...............................................................54 7.1.2 同步執行...........................................................................55 7.1.3 實驗參數...........................................................................56 即時通訊平順議程交遞服務之設計與實作-以XMPP 為例 V 7.1.4 實驗流程...........................................................................56 7.1.5 實驗環境...........................................................................57 7.1.6 實驗模擬器.......................................................................57 7.2 實驗結果與分析.........................................................................58 7.2.1 使用者服務時間/轉送訊息個數.....................................59 7.2.2 單筆訊息處理時間/轉送訊息個數.................................60 第8 章 結論與未來發展........................................................................62 8.1 結論.............................................................................................62 8.2 未來發展.....................................................................................63 參考文獻...................................................................................................65 附錄一 使用者與議程資料庫-資料表設計...........................................68 圖目錄 圖1 平順式交遞示意...............................................................................2 圖2 可移性的分類...................................................................................5 圖3 UAP 系統拓樸...................................................................................7 圖4 UAP 同時處理多項議程...................................................................8 圖5 Session handoff protocol message flow .............................................9 圖6 MIM 系統架構.................................................................................11 圖7 SIP 應用層之平順式交遞................................................................13 圖8 IMPP 所規範的IM 架構.................................................................17 圖9 XMPP 的主從式架構.......................................................................20 圖10 XML 串流示意圖..........................................................................25 圖11 SSM 的觸發事件與所觸發的系統功能.......................................28 圖12 SSM 系統架構...............................................................................30 圖13 即時通訊機器人接受特定指令...................................................33 圖14 在線狀態攔截器運作過程............................................................37 圖15 訊息攔截器的運作過程...............................................................39 圖16 轉送訊息規則...............................................................................45 圖17 SSM 的桌上電腦型客戶端介面...................................................48 圖18 SSM 的行動設備客戶端介面.......................................................49 圖19 SSM 的瀏覽器客戶端介面...........................................................49 圖20 以特別指令方式註冊SSM ..........................................................49 圖21 SSM 的單鍵啟動...........................................................................50 圖22 SSM 的單鍵啟動...........................................................................50 圖23 SSM 的單鍵啟動...........................................................................51 圖24 環狀訊息交換示意-8 位虛擬使用者...........................................55 圖25 實驗模擬器畫面...........................................................................58 圖26 轉送時間/轉送訊息個數之比較..................................................59 圖27 單筆訊息處理時間/轉送訊息個數之比較..................................60 表目錄 表1 封包的type 屬性..........................................................22 表2 封包的type 屬性..........................................................23 表3 封包的type 屬性.....................................................................24 表4 在線狀態攔截器四種情況之處理..................................................35 表5 訊息攔截器送達與送出訊息之處理..............................................39 表6 註冊使用者eori 之訊息處理.........................................................40 表7 SSM 和離線傳送訊息、遠端桌面之功能比較.............................53 表8 不同使用者個數情境下的實驗環境.............................................56 表9 實驗客戶端電腦的配備.................................................................57 表10 每個使用者所花費的訊息轉送時間...........................................59[[note]]學號: 693520099, 學年度: 9