In machine-to-machine communications, a remote sensor gathers data and sends it wirelessly to a network, where it's next routed, often through the Internet, to a server such as a personal computer. At that point, the data is analyzed and acted upon, according to the software in place.
Older systems worked similarly, using "telemetry." Telemetry technology, in many ways, was the forerunner of the more advanced M2M communications systems. Both telemetry communication and M2M communications transmit data through a sensor. The major difference between the two is that rather than a random radio signal, M2M communications uses existing networks, such as wireless networks used by the public, to transmit the data.
Telemetry systems were once the province of scientists, government agencies and other organizations. Still, telemetry technology found many uses, including in aerospace, agriculture, water treatment monitoring and wildlife science. A radio collar wildlife scientists fit onto a captured animal sends telemetry about that animal's movement and habits.
The sensors in older telemetry communications, however, were highly specialized and often needed strong power sources to transmit data. Also, data collection could be spotty if a remote sensor was located in a "dead spot." Of course, any data analysis was conducted by what we now consider antiquated computers.
Modern M2M communications represents vast improvements over these systems. Remote sensor technology advances offer increased sensitivity and accuracy. Analyzing computers and software also work at a faster pace. The explosive growth of public wireless networks is probably the biggest change that has opened M2M communications to many more sectors.
Using wireless networks makes it easier to transmit telemetry for several reasons. First, radio signals don't need to be as powerful as they once did, as cellular towers are spread over large areas to provide coverage. Older telemetry systems didn't always rely on radio signals -- some used dedicated phone lines, for instance -- but the wireless aspect allows for easier remote placement of sensors.
Find out exactly how M2M works on the next page.