# Key concepts

> Safe zone, location signature, registered device, policy, risk level: the shared vocabulary of every Ironchip product.

URL: https://docs.ironchip.com/en/empezar/conceptos/

All Ironchip products share a few ideas. This page defines them once so the rest of the documentation can use them without explaining them again.

## Location signature

An anonymous representation of the radio environment of a place (visible Wi-Fi and mobile networks), bound to the device key. It stores no coordinates and no movement history.

## Safe zone

A place, or a set of places, from which a policy allows an action: headquarters, a plant floor, the data center or the home of someone working remotely.

## Registered device

A phone, computer, USB token or card that the user has enrolled and that holds their private key.

## Policy

A set of rules that decides what can be done inside a safe zone, what happens outside it and which additional factors are requested.

## Risk level

The result of assessing an access or a transaction, with the evidence behind it. In the identity platform, [ITDR](https://docs.ironchip.com/en/identidad/administracion/itdr/) rules assign each access a risk from 0 to 100 (clean, low, high or fraud). In [fraud detection](https://docs.ironchip.com/en/fraude/conceptos/evaluacion-de-riesgo/), each transaction gets one of four levels: `low_risk`, `high_risk`, `fraud` or `unknown_risk`.