A movable network:two-level mobile IPv4

• Main Author: 邱學龍
• Other Authors: 陳文賢
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/34282077413990130003

碩士 === 國立中興大學 === 資訊科學研究所 === 92 === Mobile IPv4 is the standard of current IPv4 Mobile Network. However, it still has some problems, such as triangle routing, handoff delay, insecurity, and foreign agent’s heavy loading. Route Optimization has solved the triangle routing problem, and fast handoff has improved the situation of handoff delay and packet loss during handoff process. Even many proposals resolve some of these problems, Mobile IPv4 not meet the requirements of seamless handoff (Session Continuity) in some situations such as the internet access of bus passengers. This article has considered all possible combination of Care-of Address types of MN and MG (Co-located Care-of Address and Foreign Agent Care-of Address), and proposed the structure called “Multilevel Mobile IPv4” where the Foreign Agent (FA) of MN, called Mobile Gateway, moves together with MNs when many MNs moving together. As Mobile IPv4 protocol remains unchanged and the legacy MN can also work under its condition, this structure can decrease the opportunities of MN directly registering a remote foreign agent, increase MN’s security and reduce FA’s loading. Meanwhile, MN could also select the best effort network regarding current condition to improve user’s facility and to reach the best transmission quality. In the other hand, Route Optimization and Fast Handoff mechanics are also demonstrated in each case mentioned above to improve the performance of packet routing and handoff procedure.