在傳統的有線網路中，每一個設備要連線到網際網路中必須設定相關的IP位址資訊才可以跟其它設備連通，這些IP位址的自動設定方法一般是採用一個集中式的DHCP伺服器來統一分配IP位址相關資訊給參與網路的設備，但是這樣的方式並不適合用在MANETs的環境裡頭。由於各設備會動態的移動或是離開網路，所以DHCP伺服器並沒有辦法保證在MANETs的環境下，可以讓每一個設備都可以連線到自己。在這篇論文裡頭，我們提出一個分散式的方法來設定IP位址相關資訊給新參與的網路設備。在網路中有一些設備會負責分配IP位址相關資訊給新參與網路的設備，我們稱它為coordinator設備。每一個新參與網路的設備都會利用交換Hello message來得知距離最近的coordinator在哪裡並發出IP位址相關資訊的需求給這個coordinator設備。因為IP位址是有限的資源所以必須妥善利用，為了有效的維護IP 位址並降低通訊的所花費的成本，我們利用經常的交換Hello message的特性來建立一個virtual C-tree的架構來降低整各網路的通訊成本。因此這一個virtual C-tree的架構可用被利用來備份每一個coordinator設備的IP-Address pools的相關資訊並且收集要離開網路設備的IP位址以便減少通訊所花費的成本。 In traditional wired networks, nodes are assigned IP-related information by a centralized server like Dynamic Host Configuration Protocol (DHCP) server, but it is not suitable for Mobile Ad Hoc Networks (MANETs). Due to each node will move and leave the network dynamically, the DHCP server cannot guarantee to be accessed by each node in the MANET. In this thesis, we will present a scheme to assign IP-related information to each new-joined node. Some nodes are assigned as coordinators and responsible for assigning an IP address to a new-joined node in the network. A new-joined node will use the exchanged hello messages to find the closest coordinator and to get a new IP address from the coordinator. In order to maintain the IP-address pools efficiently, the distributed coordinators are organized as a tree topology named virtual C-tree by exchanging the hello messages. The tree is used to backup the coordinators IP-address pools, collection IP addresses from leaving nodes, and record the IP-address pools status. We evaluate the performance of the proposed scheme through simulations and the results show that our protocol has low control messages overhead on invoking an IP address from a new-joined node and IP address maintenance from the leaving nodes.
