【正文】 ism such as DHCP (a colocated careof address). When the home agent receives the register message, it will maintain a register message WP=46table in the server, where the original registered care of address will be replaced by the new registered careof address. Then a reply message will be sent to the mobile node also by wellknown port 434. OK, all the register and reply process .the register, the packet can be routed in IP layer. Among all the routing process, our thesis emphasizes on the mobile node. The work of the mobile node mainly involves two parts, the one is that mobile node receives packets from other nodes, and the other is the mobile node actively municates with other nodes. If the mobile node receives packets from other nodes, there es two condition: one way is that its position is on the home route, then it will discover that the destination address of the packets is the home address, so it receives packets. The other way is that the mobile node is on the roaming foreign link, at this time, the packet’s destination address it receives will be the care of address transmitted by the home agent. In order to municate with other nodes only with its home address, the mobile node will dispose the packets like this: First, it will shuck off the IP head, so es out the home address which be added by home agent. Second, the mobile node can use home address to send packets to the munication opposite. Generally, the home agent substitutes the mobile node to receive packets in home link, then send all the packets through the channel to the careof address, so the roaming mobile node receives the packets on the foreign link on the other hand, the mobile node maybe actively municates with other nodes. Here also two conditions: the one is the mobile node discovers that it is on the home link through agent searching, then no. 【關鍵詞】 移動節(jié)點； 數據包； 家鄉(xiāng)鏈路； 代理搜索； 外地鏈路； 轉交地址； 移動通信； 設計與實現； 隧道技術； 目錄 1 引言 .......................................................................................................................... 1 2 移動通訊中移動 IP 節(jié)點技術的實現 ............................................................ 1 移動 IP 節(jié)點的關鍵技術 ................................................................................ 1 移動 IP 技術 的工作過程 ................................................................................ 2 3 移動 IP 技術的具體方案 .......................................................................................... 5 技術優(yōu)化概述 ................................................................................................... 5 移動節(jié)點的切換操作 ....................................................................................... 5 仿真實現 ........................................................................................................... 6 4 移動 IP 技術中的關鍵環(huán)節(jié) ...................................................................................... 7 代理搜索 ........................................................................................................... 7 注銷注冊 ........................................................................................................... 7 傳遞數據包的選路 .....................................................................................