The possibility of seamless switching between 3G and WLAN

After the network has satisfied the initial connection dream, people's demand for the network has entered into the desire for the movement,

Because mobile can bring people freedom, mobile network can meet the needs of all the times and everywhere.

What will be the future of mobile networks,

3G, Wi-Fi, Bluetooth and wired network will make up what kind of network eco-ring?

Fixed network and mobile network Fusion Technology (FMC) in Asia and the world is still in the neonatal period, it is not a mature and can be truly commercially accessible business. Recently, the technology has been developed, from a technical point of view, the fusion between fixed and mobile networks can be implemented on a multi-level, such as business layer, network layer and terminal level. Network layer technology such as SBC (Session Border Controller, conversation layer boundary controller) equipment, can provide the realization of a variety of IMS (Internet Multimedia subsystem, Internet multimedia subsystem) network system integration. The fusion of terminal side can adopt a variety of wireless network connection mode (such as 3G, wireless access technology without band limit IEEE802.11, etc.). Now the integration technology that supports the terminal level is mainly Uma (unlicensed mobile access, license-free mobility). As early as January 2004, UMA technology was jointly initiated by a number of industry-leading operators and vendors to develop and promulgate a set of standards to extend mobile voice and data in Gsm/gprs to be used in unlicensed spectrum technologies such as Bluetooth and wireless LANs. Finally, the standard is encouraged to be adopted by the world's formal standards organizations. September 2, 2004, companies involved in the technology jointly issued the first UMA technical standards. April 8, 2005, the 3GPP organization agreed to the standard as part of 3GPP release 6. Having achieved the above two objectives, the company that participates in UMA technology has agreed to cease its activities as an independent organization and to continue to develop such technology within the 3GPP organization. (Computer science)

BT is the first operator to provide a fixed and mobile network fusion solution, by making full use of the high-speed broadband network at the user's home wlan/Bluetooth, users can use a phone number to access mobile communications outside, while at home through a fixed broadband network to achieve high-speed connections. However, the actual operation is not very ideal, there are many reasons. After a number of operators have tried, technology is still in development and development.

July 26, 2005, Ericsson and BB Mobile (a company of SoftBank Group) jointly demonstrated the world's first seamless handover of voice and IP multimedia subsystems based on the circuit domain between 3G Mobile communications and wireless LANs.

So far, technical demonstrations or promotional materials for the consolidation of fixed and mobile networks are divided into the following categories (the main introduction is WLAN, of course, Bluetooth is an alternative technology):

(1) The switch between WCDMA and WLAN. Since WCDMA is now based on the circuit domain, this switch is mainly between the circuit domain and the IP domain switch.

(2) switching between HSDPA and WLAN. Also because the voice business of HSDPA is still based on the circuit domain, although its data service is based on IP, so this switch, for voice service, still is the switch between the circuit domain and the IP domain.

(3) 3GPP2 switching based on full IP between the WLAN and the Wi-Fi. With two vendors offering solutions, Hitachi (China) Research and Development Co., Ltd. provides a demo based on EVDO systems.

October 2005, Hitachi (China) Research and Development Co., Ltd. in 2005 China International Communication Equipment Technology exhibition demonstrated the first time in the world in the 3G and Wireless LAN based on IMS video telephony business Seamless switching. During the demo, when switching from 3G to WLAN, users will not feel latency and packet loss, which can be said to be a seamless switch. The demo is based on the IETF mobile IP technology, where a variety of networks overlap regions, users can choose their own circumstances, such as price, bandwidth or QoS to choose the right network. While the user is doing business without any impact or disruption, the demo also provides a demo of the mobile video conferencing business based on 3GPP2 IMS, which is also the first time. This presentation looks forward to the future human mobile communications can make it possible to provide ubiquitous connectivity.

3G System covers a wide range of users to ensure uninterrupted connection between the network, and in the case of high-speed movement, but also to ensure a stable quality of service. However, the data transfer rate is relatively low, some of the hot spots with large service volume may be due to the limited capacity of 3G network and can not guarantee better service quality. But the WLAN system's coverage scope is small, only exists in the hot spot area, but the data transmission rate is high, may realize the broadband network. At the same time, the service cost of WLAN network is relatively cheap compared to 3G network. It can be said that the 3G system and WLAN systems are complementary.

For operators, WLAN deployments are cheaper and faster, and can be deployed in service hotspot areas and 3G network coverage blind spots.

Because the future ip-based voice service is bound to replace the voice service based on the circuit domain, Hitachi (China) Research and Development Co., Ltd. developed this ip-based mobile switching technology to demonstrate the future development trend of mobile communication technology.