移動視訊偵搜隨意網路能量平衡路由法的設計與實作

Abstract

有鑒於無線網路傳輸技術的進步，視訊偵搜系統也從固定式進入了行動的模式，使用能任意移動的裝置(筆記型電腦、PDA、3G行動電話等等) ，結合IP網路及數位取像等技術，形成行動視訊偵搜系統與服務。 本論文以張家瑋[Cha07]所設計的利用鄰居資訊路由法的行動視訊偵搜系統為基礎，針對應用隨意網路建構行動視訊偵搜系統，在選擇路徑所產生的能量問題做主要的研究。我們想要在隨意網路系統選擇路徑時，能加入能量的考量，但同時也能保証偵搜視訊的品質，以建立移動視訊偵搜網路的服務。由服務的需求，我們進一步的探討現存的路由方法在我們想要的服務上不足的地方，主要有兩個研究的問題： 1. 如何能取得網路裡其他節點的能量資訊？ 2. 如何能選擇建立有能量平衡使用考量的傳輸路徑？ 以[Cha07]所設計的鄰居資訊列表(NIL)與品質路由演算法為基礎，利用NIL做修改在網路層設計了能量鄰居資訊列表 (ENIL)搜集建構法和能量平衡路由演算法(EBRA)，來解決所提出的兩個主要研究問題。其中ENIL的搜集建構可以透過節點週期性相互廣播(broadcast)來保持各節點傳輸範圍內的最新鄰居資訊，包含IP位址、位置座標、傳輸速度、剩餘能量和狀態，其中剩餘能量資訊是為了我們在之後建立路徑時，能幫助我們求出各節點的剩餘傳輸時間( )；而狀態資訊是為了當有多個任務要執行時，提供我們判斷節點是否能夠被使用。而EBRA是根據一個節點ENIL中周圍節點的位置座標、傳輸速度和剩餘能量，來選擇符合傳輸速度的節點傳送路徑要求封包(RREQ)，由於符合的節點不一定只有一個，所以在最後節點可能接收到多個RREQ，選擇封包資訊裡 值較大的，以建立一條在傳輸速度品質要求下能傳輸較持久的路徑。 由於在[Lia06]、[Cha07]所設計的移動式視訊偵搜系統，都只是針對單一傳輸任務的路徑選擇作考量，所以在論文中我們利用ENIL的狀態資訊和802.11的CSMA/CA技術，來掌握相鄰節點的狀況，以避開使用中的通道，再運用能量平衡路由法在可用網路上進行另一任務路徑選擇。 在實作方面，我們延用張家瑋[Cha07]的實作技術，改寫路由程式，及利用timer設定，區隔RREQ接收到的時間，達成路徑選擇的動作。我們在ENIL的資料表加入能量和狀態資訊，且採用SQL2000資料庫來存取資訊；而EBRA的設計則利用Visual Basic.NET改寫了可以自動依照本論文需求去尋找路徑的程式。接著我們使用此程式完成能量平衡路由法的搜尋和路徑建立，和當有一個影像任務在執行時，選擇第二影像任務的路徑。可以展示EBRA能找到之維持最長時間傳輸路徑，同時也能維持傳輸的品質。

Because of the progress of the transmission technology in the wireless network, video surveillance has been from fixed type to action type. Devices of moving arbitrarily(notebook, PDA, 3G mobile phone, etc.) combine with IP network and video surveillance to form mobile video surveillance system and service. Based on the neighbor information list routing for mobile video surveillance systems, designed by Chia-Wei Chang [Cha07], this thesis researches the energy issue of choosing path for mobile video surveillance system over ad hoc networks. When ad hoc networks systems choose the path, we want to consider energy elements, and keep the quality of video surveillance at the same time to establish mobile video surveillance services. For services, we further explore insufficiency of the existing routing method; therefore, there are two main research questions: 1. How to obtain neighbor node’s energy information in ad hoc networks? 2. How to choose and establish a transmission path of energy balance? Based on neighbor information list (NIL) and quality-based routing algorithms, designed by Chia-Wei Chang [Cha07], the thesis modifies NIL to design energy neighbor information list(ENIL) and energy balancing routing algorithms (EBRA) in the network layer for resolving the two main research questions. ENIL allows nodes to broadcast among each other periodically and collects neighbor’s latest information in the transmission range of each node. It includes IP address, location coordinates, data rate, remaining energy and state. Remaining energy information is to find out remaining transmission time (RT(t)), when we establish path; status information is to determine whether the use of nodes, when there are multiple mission to be implemented. EBRA is based on location coordinates, speed and remaining energy in ENIL to select nodes corresponding with data rate to transmit routing request packet (RREQ). Because it is not necessarily that there is only one node, the final node may receive many RREQs and select the largest RT(T) in the packet information to establish a more lasting path with quality of data rate. [Lia06] and [Cha07] design mobile video surveillance systems, which is aimed at single mission, so in the thesis, we use state information of ENIL to know the situation of the adjacent nodes and CSMA / CA of 802.11 to avoid the using channel, and then use energy balancing routing to choose another path in available ad hoc networks. We apply the Chia-Wei Chang’s technology [Cha07] to rewrite routing programs and utilize timer settings to divide RREQ’s receive time, and then reach the movement of path choice. We add information of energy and status in the ENIL, and use SQL2000 database to access information; EBRA utilizes Visual Basic.NET to rewrite the program for searching route automatically according to the demand of this thesis. We use this program to run the energy balancing routing to search and establish path, and when there is a video mission in the implementation, we establish the route of the second video mission. The EBRA can find out the path of maintaining the longest time and quality of transmission.