| IntroductionUntil now , the growth of the mobile phone user nearly depends on the voice business. Just recently ,data business begins to benefit the contribution of the operator's income. At present ,the competition between the operators is fiercer and fiercer, to offer to user diversified data value-added service becomes an effectual means that the operators raise their competition.Therefore,the research, development and disposing of mobile wireless internet become a new field of Internet communication technology. The fastest rate that the GPRS terminal equipment offers to is 171 kb / s, 3G terminal equipment is 2 Mbs / s .Obviously, the data-rate WLAN offered is much higher than GPRS's, and even 3G's.So the WLAN technology can offer wide supplement for any honeycomb technology perfectly. However,the coverage of the WLAN is much smaller than honeycomb technology,so considering the economical of the investment, the WLAN can only be disposed in the focus areas, such as airport, hotel etc.. Merging can offer many benefits,such as high access rate of WLAN and the wide coverage of GPRS,WCDMA, it will play a positive role in the development of the mobile wireless internet. 1.Development of the Mobile Communication Beyond doubt ,the mobile communication which has went through 1G,2G comes to the service that developed most fastly .Now the 3G communication system based on CDMA technology is experimented and deployed by the operators all over the world, the most important factor impelling the 2G to 3G is the need for providing higher data rate service to the mobile users .China Uincom has built the GSM network all round the country ,the wireless access network is based on WCDMA wireless technology in the evolution of GSM network to 3g network. 2.Mobile IP The mobile IP technology is the core of the mobile internet. It defines kinds of function entity that must be depended on the mobile protocol: mobile node(MN) ,home agent(HA),foreign agent(FA). The operation in course of the mobile IP protocol can be simply described as follows: (1)The data sent to the MN reach belonging network through standard IP route. (2)The HA intercept the data sent to the MN, then deliver it to COA of MN by tunneling technology. (3)The FA decapsulates the tunneling , then deliver it to the MN. (4)As to the data that the MN send out, standard IP route deliver each data to destination, i.e. CN. In this way, a mobile user may not reconfigure ,restart the facility during the process of moving from one subnet to another subnet,even more noteworthy ,users do not need restart application either ,thus the transparency operating realized! For the purpose that user can be offered to ubiquitous Internet access in wireless and wired environment, the concept of "multi-interface/ multi-link" is mentioned. HA can manage many connections from the mobile terminal. The method of "multi-interface/ multi-link" can support high rate handing over and fluent roaming between different networks (Wireless and wired). Handing over amount networks is not only possible ,but also favorable ,because the mobile user can choose the best network in using uninterruptible service state. 3.Integration of mobile service and packet-based service GPRS (General Packet Radio Service ) is deployed by added two nodes (SGSN,GGSN) in the GSM network and packet control units for wireless packet access in the sub-base station system .It can offer entirely mobile and widely coverage packet-based service. Its technology has combined data communication technology and mobile communication technology. GPRS can provide high rate wireless access service (up to 171kbit/s), and take tactical way on expenses, so that users can access internet at any time,realize the "online at any time" actually. For the limit of the GPRS's bandwidth, WLAN is deployed in focus area. WLAN is basely composed of wireless network card,access point,access controller and identify system .Compared with GPRS ,it can maintain high rate and data b...
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