I can't understand the phone bill of mobile communication network. Thank you for your help. What are these three ISMG GPRS MMS messages?

The construction of SMS Gateway (ISMG) can provide a safe and fast channel for data exchange between SP and SMS Center (SMSC), so that mobile phone users can communicate with SP through SMS, receive information services provided by SP, and complete corresponding functions such as billing collection, business management and network management.

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MMS is the abbreviation of multimedia message service, which means multimedia short message service in Chinese. This service is based on the standards of 3GPP and WAP forum. In the aspect of multimedia short message service, with the support of GPRS network or cdma2000 1X network, WAP wireless application protocol is used as the carrier to transmit video clips, pictures, sounds and words. It supports various high-speed data services, such as voice, Internet browsing, e-mail, conference TV and so on. Realize instant multimedia information transmission from mobile phone end to end, from mobile phone terminal to Internet or from Internet to mobile phone terminal. The emergence of this service can replace some functions of e-mail, and can be used as an electronic postcard to provide extremely rich services. The biggest obstacle to the development of this service is the speed limit of the current 2.5G network. Slow network speed directly leads to high tariffs. Although the price has dropped a lot, it is still unbearable for most users.

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What is GPRS?

GPRS (General Packet Radio Service), as a transition technology from the second-generation mobile communication technology GSM to the third-generation mobile communication (3G), was proposed by British BT Cellnet Company as early as 1993, which is one of the contents of GSM Phase2+ (1997) specification, and is a mobile packet data service based on GSM, providing users with mobile packets.

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