SMS agreement

The SMS protocol supported by mobile phones is also a multimedia protocol. Currently, there are three types of SMS, EMS and MMS.

SMS
SMS (Short Messaging Service): SMS service. It is the earliest short message service, and it is now a short message service with the highest penetration rate. Through it, mobile phones can send and receive text messages to each other. The content is mainly text, digital or binary non-text data. Currently, such short message is The length is limited to 140 bytes. SMS is popular with users for its simple and convenient use. It has been rapidly popularized, but it is always the first generation of wireless data services. There are technical standards in terms of content and application.

EMS
EMS (Enhanced Message Service) means Enhanced Short Message Service. Compared to SMS, it has the advantage of sending simple text, sounds, and animations, in addition to sending short text messages like SMS. And its greater advantage is that EMS can still run on the existing SMS running GSM network, and there is no difference in the transmission route and operation method. The standard is open-ended, so any third-party company or individual interested in EMS can develop application software and services on this platform. However, due to the technical incompatibility of various mobile phone brands, the mutual transmission between the same brands of mobile phones can only be realized during actual use, and thus the practicability needs to be further improved.

MMS
MMS is the abbreviation of Multimedia Messaging Service. Chinese translation is a multimedia information service, also known as “MMS”. It is the latest standard of multimedia information standards developed in accordance with the 3GPP standards and the WAP Forum. Its biggest feature is its support for multimedia functions. Supports GPRS, CDMA 1X, 3G, and EDGE to transmit video clips, pictures, sounds, and texts using the WAP wireless application protocol as a carrier. In addition to transmission between mobile phones, transmission can also be between mobile phones and computers. . What's unique about MMS-enabled mobile phones is their built-in media editor that allows users to easily write multimedia messages. If the phone has a built-in or external camera, users can create information or e-postcards in PowerPoint format and send them to friends or colleagues. At present, this application service has gradually matured into a mainstream SMS format.

MMS is the "third generation short message service" following SMS (text messaging service) and EMS (enhanced short message service). SMS can only send and receive text messages, EMS can add ringtones, simple graphics, and simple animations to text messages. MMS greatly expands the types of media that can be sent and received. Text, simple pictures, and ring tones can be transmitted. Complex pictures such as photos, The transmission of large-scale charts and music clips and video clips can better play the role of MMS.

The industry standard of MMS is established by two organizations, WAP Forum (WAP Forum) and 3GPP (3G Partnership Project: 3G Partnership Project). Therefore, MMS is designed to operate at the upper layer of the WAP protocol. It is not limited to the transport format. It supports both circuit-switched data and general packet radio services. Its working principle is the use of high-speed transmission technology EDGE (Enhanced Data rates for GSM Erolution is a new technology to increase the data rate, is the transition from GSM to the third generation of mobile communication system IMT-2000. It is also known as GSM 384, Because this technology can make the data rate from the current 9.6kbit/s to 384kbit/s, this rate can support voice, Internet browsing, e-mail, conference TV and other high-speed data services) and GPRS support. WAP (Wireless Application Protocol) transmits video, pictures, sounds and texts for carriers.