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# NIDLTDOAConfiguration

A configuration that enables Downlink Time-Difference-of-Arrival ranging.

```
class NIDLTDOAConfiguration
```

## Overview

Run an instance of this configuration to participate in a session that supports the Downlink Time-Difference-of-Arrival (DL-TDOA) feature. Before creating an instance of this class, call [`supportsDLTDOAMeasurement`](/documentation/NearbyInteraction/NIDeviceCapability/supportsDLTDOAMeasurement) first to ensure device support.

## Topics

### Creating a configuration

[`init(networkIdentifier: Int)`](/documentation/NearbyInteraction/NIDLTDOAConfiguration/init(networkIdentifier:))

Initializes a Downlink Time-Difference-of-Arrival (DL-TDOA) configuration for a specific tracked area.

[`init(networkIdentifier: Int, discoveryMethod: NIDLTDOAConfiguration.DiscoveryMethod)`](/documentation/NearbyInteraction/NIDLTDOAConfiguration/init(networkIdentifier:discoveryMethod:))

Initializes a DL-TDOA configuration with a network identifier and discovery method.

### Identifying the network

[`var networkIdentifier: Int`](/documentation/NearbyInteraction/NIDLTDOAConfiguration/networkIdentifier)

A unique identifier for a Downlink Time-Difference-of-Arrival network.

### Specifing the discovery method

[`var discoveryMethod: NIDLTDOAConfiguration.DiscoveryMethod`](/documentation/NearbyInteraction/NIDLTDOAConfiguration/discoveryMethod-swift.property)

The technology your app uses to discover DL-TDOA anchors.

[`enum DiscoveryMethod`](/documentation/NearbyInteraction/NIDLTDOAConfiguration/DiscoveryMethod-swift.enum)

The technologies an app can use to discover Downlink Time-Difference-of-Arrival anchors.

## Relationships

### Conforms To

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`NSCoding`](/documentation/Foundation/NSCoding)

[`Hashable`](/documentation/Swift/Hashable)

[`Sendable`](/documentation/Swift/Sendable)

[`Equatable`](/documentation/Swift/Equatable)

[`NSSecureCoding`](/documentation/Foundation/NSSecureCoding)

[`NSCopying`](/documentation/Foundation/NSCopying)

[`CVarArg`](/documentation/Swift/CVarArg)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

### Inherits From

[`NIConfiguration`](/documentation/NearbyInteraction/NIConfiguration)

---

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