When you text a friend, coworker, or family member, you are typically texting from one phone to another. If you are trying to text many people at the same time, you will most likely use a web-based application. This application allows you to send messages to your entire list of end-users or to subsets of that list. Most applications let you sort users and track messages.
Conceptually, sending SMS messages on a large scale has five steps.
If the end user is not available, the carrier's SMSC stores the message until a later time for subsequent retransmission. Thus, SMS operates as a store-and-forward service unlike a voice call. Each carrier has different policies about how long they will hold a message, but after that period of time expires, the message is deleted. Occasionally an SMS text message delivery is delayed, or not delivered at all, particularly if an end user's phone is turned off for an extended period of time. Some other causes include:
This store and forward delivery system is one reason why SMS is both more reliable—and less reliable—than voice during an emergency. During an emergency, voice lines can get jammed. SMS messages are more likely to go through because system overload can be mitigated by temporary message storage. However, some messages may not be stored long enough and may be lost—which is why some people think SMS is less reliable than voice.
Move ahead to learn more about choosing a web-based Application.