TCP in Mobile Networks

• Main Authors: Kao Chang-Jung, 高長榮
• Other Authors: Liao Wanjiun
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/29675103936203373345

碩士 === 國立臺灣大學 === 電機工程學研究所 === 90 === Advent technology of mobile computing devices has accelerated the development of wireless networks in recent years. To date, mobile devices, such as notebooks, mobile phones, and PDAs, can connect to the Internet via specific wireless network system nowadays. However, due to the feature of mobility in the mobile devices, there are different characteristics compared with the wired one, such as higher bit error rate in the wireless link and temporary data disconnection due to handoff between base stations. In wireless environments, the protocols designed for wired network might degrade their performance due to the effects mentioned above. Thus, the issues of TCP in mobile networks will be studied in this thesis. TCP had been designed in wired networks to provide reliable and ordered data transmission service. However, TCP degrades its performance due to the features of high bit error rate and mobility when being adopted in mobile devices. Consequently, this thesis attempts to propose a solution to the problems. The main contribution of this thesis is to propose a new sender-side TCP extension mechanism to solve the inefficient bandwidth utilization resulting from handoff. In addition, we also simulate the performance of the proposed mechanism. The results prove the enhancement of bandwidth efficiency by adopting the proposed mechanism in TCP sender.