What do SMS, EMS and MMS mean?

The English name of Short Message Service is short message service, abbreviated as SMS. Although it only rose in China in recent two or three years, it has a history of 1 1 year. The earliest short message was 1992 from a computer to a mobile phone in Britain. The mobile phone number belongs to Vodafone and uses GSM network. You know, GSM was still a rare thing at that time, and people at that time were not very smart. SMS is only used to inform users that there is voice mail. After 1998, users did not call as much as before, which forced operators to rack their brains to find financial resources. So from Europe, the packaging and promotion of short message service formed a craze at that time. Various mobile phones supporting SMS are constantly being introduced, which is the icing on the cake.

At that time, China was still in the era of castles, and mobile (telecom) Unicom and the like were still on the price. You cut me and I stabbed you. Gradually, I feel that it is not the way out. Coupled with the strong stimulation and temptation brought by the fabulous success of Japanese I-Mode, China Mobile could not sit still at first. During the Sydney Olympic Games in September 2000, we cooperated with Sina, Sohu, Tsinghua and Lingtong.com to launch the "Global Olympic News" information on demand service. I started to engage in Monternet similar to I-Mode mode, but it was limited to GSM users at that time. Unicom Unicom immediately followed up in the letter. China's short message market is also a prosperous scene.

Of course, if there is demand, there will be a market, and enhanced messaging services will appear. This standard was put forward by Ericsson and was supported by most manufacturers except Nokia (because Nokia wanted to develop intelligent messaging itself).

EMS support:

1. Format text, including left-right alignment, centering, font, bolding (Chinese is not allowed because we use dot matrix font), adding black, underlining, etc.

2. A simple black-and-white picture, including at most 16* 16, 32*32, 96*64 pixels.

3. Sound has 65,438+00 predefined types, which can be edited by users, but the maximum length cannot exceed 65,438+028 bytes. Like the Ericsson T65 I used before, the maximum length can only be 80 bytes, but now Sony Ericsson T 102 is only 40 bytes.

4, animation, support 16* 16, 8*8 pixels (as for Nokia's flash SMS and the so-called overlord SMS, technically speaking, as long as the data coding method is set to 16-bit unicode and the information starts with 000 1, it is not something profound).

However, due to the non-uniform EMS format standards and the occupations of some manufacturers, mobile phones of different brands often fail to send each other. For example, the pictures sent by Ericsson to Nokia are completely garbled, and even the pictures sent by Sony Ericsson T202 to my old T65 can't be displayed normally. It may be the EMS version. Now EMS is version 5.0.

As a direct upgrade version of SMS, EMS has the same characteristics as SMS:

1, adopts the store-and-forward mode, and every short message is stored in the short message center SMSC before forwarding, which brings its second advantage and third disadvantage.

2. When the other party is turned off, it can be stored in SMSC and sent to the other party after the other party is turned on and connected to the network. There is no problem that both parties have to open P2P software on the computer.

3. When there are many people sending messages during the Spring Festival and Valentine's Day, the channel will be blocked and cannot be sent out. Everyone has experienced the same pain, mainly because an SMSC can only handle hundreds of short messages per second, and it is difficult to upgrade. Of course, there are reasons for not using a dedicated SMS channel.

To put it more bluntly, there are cases where you can't send or receive short messages, mainly including: 1, the network signal is too weak; 2. There are too many groups at a time, which causes the above reasons; 3, network delay, just wait a minute; 4, the problem of network interoperability, mobile communication, generally does not make sense.

4. Although the storage mechanism is adopted, it is impossible to effectively monitor the content and filter reactionary, junk advertisements and pornographic jokes. Hehe, now the text messages are all a bunch of snakes and rats.

5. The sent SMS can be tracked to know whether the other party has received it, which is also different from ordinary pagers.

6. It can be transmitted together with voice, data and fax because the same channel is used.

Because SMS has many advantages, we can't put it down, and because it has insurmountable shortcomings, manufacturers simply introduced a higher standard-MMS service (MMS for short), instead of upgrading SMS.

MMS supports audio and video transmission and should be the ultimate version of SMS. Because SMS is just a way of communication, and the way of communication, from text to voice, must be video in the end. The last step is to meet. Since we can meet anytime, anywhere, why are you still holding a mobile phone?

MMS does live up to expectations. In addition to all the advantages of EMS/SMS, it also uses special data channels to send, supports email (SMTP), Internet (TCP/IP) and MIME (actually, it is also a bottom-level email protocol), and solves the channel congestion problem to the greatest extent. But it would be better if peer-to-peer (P2P) can be adopted. This is a development trend of the Internet in the future, and it is still very luxurious on mobile phones now.

Of course, some people say that the next generation of MMS is FMS(Flash Message Service), because Flash can transmit animation and the file size is small, but I think it is only an extension of MMS, because it is all video. In terms of technical implementation, we only need to add a file format support, and there is no need for a greater breakthrough.

Of course, EMS also refers to express delivery companies.

With tnt, FedEx, ups, etc. It is the largest international express delivery company.

I also found one online:

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