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# CBATTRequest

A request that uses the Attribute Protocol (ATT).

```
class CBATTRequest
```

## Overview

The [`CBATTRequest`](/documentation/CoreBluetooth/CBATTRequest) class represents Attribute Protocol (ATT) read and write requests from remote central devices (represented by [`CBCentral`](/documentation/CoreBluetooth/CBCentral) objects). Remote centrals use these ATT requests to read and write characteristic values on local peripherals (represented by [`CBPeripheralManager`](/documentation/CoreBluetooth/CBPeripheralManager) objects). Local peripherals, on the other hand, use the properties of [`CBATTRequest`](/documentation/CoreBluetooth/CBATTRequest) objects to respond to the read and write requests appropriately, using the [`respond(to:withResult:)`](/documentation/CoreBluetooth/CBPeripheralManager/respond(to:withResult:)) method of the [`CBPeripheralManager`](/documentation/CoreBluetooth/CBPeripheralManager) class.

## Topics

### Requesting to Read and Write Characteristic Values

[`central`](/documentation/CoreBluetooth/CBATTRequest/central)

The remote central device that originated the request.

[`characteristic`](/documentation/CoreBluetooth/CBATTRequest/characteristic)

The characteristic to read or write the value of.

[`value`](/documentation/CoreBluetooth/CBATTRequest/value)

The data that the central reads from or writes to the peripheral.

[`offset`](/documentation/CoreBluetooth/CBATTRequest/offset)

The zero-based index of the first byte for the read or write request.

## Relationships

### Conforms To

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

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

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

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

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

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

### Inherits From

[`NSObject-swift.class`](/documentation/ObjectiveC/NSObject-swift.class)

---

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