Principles of instant messaging and short message transmission

The channel resources of wireless communication are limited. Only when you have communication needs will you assign channels to users.

Instant messaging is real-time and needs one party to send and the other party to receive. Therefore, before the dual communication, the system has established a dedicated channel for both parties.

The real-time requirement of SMS is not strong, and it will be received immediately if it is not sent here, so the communication system will choose the right time to send the information according to the busy degree of the channel, so there will be a delay.

Even if the communication effect is good, it consumes a lot of resources. SMS is delayed, but the configuration is more flexible.