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| 5 | GPRS (General Packet Radio Service) (簡訳:GPRS (一般パケット無線サービス)) | ----------- | |
| ComputerWeekly.com | 2024-04-25 02:50 | ????0? | |
| Even though it is not used as often, GPRS is still relevant today, as it is widely compatible with networks and mobile devices. Countries like Canada, China and Switzerland still use 2G and 3G networks -- all with plans to sunset the technology within the next few years. All major carriers in the United States no longer offer 2G or 3G services, and other countries like Japan have also retired the technologies.Sometimes called a 2.5G network, GPRS provided data rates from about 56 to 115 Kbps and uninterrupted connectivity to the internet for mobile phones and computers. By comparison, GSM provided data rates of around 9.6 Kbps. However, GPRS by itself did not offer the mechanisms required to browse the internet. To enable seamless internet access, Wireless Application Protocol (WAP) was needed. It emerged in 1999.The key characteristics of GPRS are quick, for the time, data connections -- depending on the signal strength and coverage -- and the facilitation of mobile application development. So, GPRS enabled capabilities such as file transfer; online chat; and mobile, web and multimedia applications, as well as video conferencing platforms, on mobile devices and laptop computers.GPS is a satellite-based navigation system powered by approximately 31 satellite systems in orbit owned and operated by the U.S. Department of Defense but available for general use worldwide. It enables GPS receivers, including consumer devices, like smartphone navigation systems, to pinpoint their geographic location. GPRS, on the other hand, is based on GSM and other services, such as SMS, MMS and circuit-switched cellular phone connections.In theory, GPRS packet-based services cost users less than circuit-switched services since communication channels are being utilized on a shared-use, as-packets-are-needed basis rather than dedicated to only one user at a time. It was also easier to make applications available to mobile users because of the faster data rate. As GPRS became more widely available, along with other 2.5G and 3G services, mobile users of virtual private networks (VPNs) were able to access the private network continuously over wireless rather than through a rooted dial-up connection. -- ???????? | |||
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