# Machine-to-machine communication

> Machine-to-machine (M2M) communication is automated data exchange between devices without human involvement — meters reporting consumption, controllers reporting status, systems accepting remote commands.

- Also known as: M2M, machine to machine, telemetry
- Last reviewed: July 29, 2026

## How it works

A field device initiates a session on a schedule or when an event occurs, transmits its data, and disconnects. Legacy M2M frequently used dial-up modems over analog lines; modern equivalents use cellular data, but the field equipment is often too embedded or too long-lived to replace, so the analog interface has to be preserved.

## Why it matters

M2M lines are the easiest to forget in a migration inventory precisely because nobody uses them interactively. A meter that stops reporting produces no complaint — it produces estimated billing, or a fault that goes unnoticed until someone visits the site.

## Common use cases

- Utility meter reading and automated consumption reporting
- SCADA telemetry and remote control of field equipment
- Environmental and equipment status monitoring

Low visibility is the risk. An M2M line that fails generates no phone call — only a gap in
data that may not be noticed for a billing cycle.

## Common misconceptions

**Claim:** M2M lines are low priority because no one is on the phone.

**Correction:** They are low visibility, not low importance. Unreported meter data and undetected equipment faults both carry real cost, and neither announces itself.

## Frequently asked questions

**How do I find M2M lines during an inventory?**

They rarely appear as 'phone lines' in records. Look for lines terminating at equipment rooms, plant rooms, meter cabinets, and roof installations, and check for modems attached to control systems.

**Can legacy analog M2M equipment be kept?**

Usually yes. An appliance presenting an FXS port lets the existing modem dial as before while the transport moves to cellular, which avoids replacing embedded field equipment.

## Sources

- [Copper Retirement](https://www.fcc.gov/general/copper-retirement) — Federal Communications Commission


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Canonical page: https://dataremote.com/newsroom/definitions/machine-to-machine-communication
Organization: DataRemote, Inc. — POTS line replacement, cellular failover, and fixed wireless access solutions. https://dataremote.com