Why doesn't the long message show that it has been delivered?

Because the other party's mobile phone is turned off, or there is no signal, etc., you have not received your message, so your mobile phone will not show that it has been delivered.

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In 20 14, China Mobile announced that it would create a new service entrance for users in the era of mobile internet through "unified communication". This move is interpreted by the industry as: giving up SMS and embracing unified communication.

China Mobile's "new SMS" will be charged according to the traffic. As part of the "Unified Communications" business plan, informed sources revealed that the business is expected to be unveiled in the middle and late June this year, and it is expected to be commercialized before the end of 20 15.

At the beginning of the development of short message service, the sending and receiving of short messages started from mobile phones, and finally went to mobile phones, passing through GSM network /CDMA network, short message center and other network elements; With the emergence of short message on demand and customized services, mobile phones, Internet sites and short message value-added service systems can send short messages to each other. Internet sites and short message value-added service systems have become new network elements, while GSM/CDMA networks and short message centers still maintain the core position of short message networks. With the emergence of PHS mobile phone based on fixed telephone network in China, the short message service has been extended to fixed network, and the terminal is no longer limited to mobile phone. PHS mobile phones or dedicated fixed terminals can be used as the sender and receiver of short messages, and the network foundation is no longer limited to digital mobile networks such as GSM/CDMA networks. Fixed network can also become the network foundation of short message, and the elements of short message network have changed significantly.