## Purpose

NSR ECDIS NES-3000 supports operation as a standalone station and as part of a navigation bridge.

When operating as part of a navigation bridge, ECDIS connects to the bridge's internal network, where information exchange occurs between network nodes.

ECDIS is a network node. To separate functional responsibilities among multiple nodes (ECDIS) on the network, each node is assigned a role: **Master** or **Backup**.

```{note}
A **Master** or **Backup** can operate outside the bridge's internal network.
```

There can be only one **Master** ECDIS on the network. All other ECDIS units are **Backup**.

**Master**:

- Has no functional restrictions
- Is the source of navigation data for Backup units

```{note}
The restrictions on a **Backup** ECDIS are designed to ensure the integrity of navigation data on the network. All configuration changes are made only on the **Master** ECDIS and are automatically synchronized to the Backup units.
```

**Backup** cannot:

- Configure sensors
- Perform manual observations
- Apply corrections to position, heading, and speed
- Install ENC and their updates
- Perform manual ENC updates
- Perform dead reckoning, including with total drift

```{important}
Bridge mode is available ONLY when integrating ECDIS units from the same manufacturer.
```

A **Backup** performs all the functions of a **Master**, except for the prohibited ones. Additionally:

 - Synchronize the ENC collection with the **Master**
 - Synchronize settings with the **Master**
 - Synchronize routes with the **Master**

```{attention}
The **Cloned key** option is only available in **Bridge** mode.

The **Cloned key** supports a maximum of 5 stations simultaneously.

The **Cloned key** clones the HW_ID.

The **Cloned key** allows using one set of ENC cells on 5 workstations.

The **Cloned key** only works when the primary license key is present on the network.
```
