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# NEFilterFlow

The abstract base class for types that represent flows of network data.

```
class NEFilterFlow
```

## Topics

### Inspecting flow properties

[`URL`](/documentation/NetworkExtension/NEFilterFlow/url)

The flow’s HTTP URL.

[`identifier`](/documentation/NetworkExtension/NEFilterFlow/identifier)

The unique identifier of the flow.

[`direction`](/documentation/NetworkExtension/NEFilterFlow/direction)

The initial direction of the flow: incoming or outgoing.

[`NETrafficDirection`](/documentation/NetworkExtension/NETrafficDirection)

A type to represent the direction of network traffic.

[`NEFilterFlowBytesMax`](/documentation/NetworkExtension/NEFilterFlowBytesMax)

The maximum number of bytes to pass or peek for a flow.

### Source app identification

[`sourceAppUniqueIdentifier`](/documentation/NetworkExtension/NEFilterFlow/sourceAppUniqueIdentifier)

A byte string that uniquely identifies the binary for each build of the app that is the source of the flow.

[`sourceAppIdentifier`](/documentation/NetworkExtension/NEFilterFlow/sourceAppIdentifier)

A string containing the identifier of the source app of the flow.

[`sourceAppVersion`](/documentation/NetworkExtension/NEFilterFlow/sourceAppVersion)

The short version string of the app that is the source of the flow.

[`sourceAppAuditToken`](/documentation/NetworkExtension/NEFilterFlow/sourceAppAuditToken)

The audit token of the source application of the flow.

[`sourceProcessAuditToken`](/documentation/NetworkExtension/NEFilterFlow/sourceProcessAuditToken)

The audit token of the process that created the flow.

## Relationships

### Conforms To

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

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

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

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

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

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

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

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

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

### Inherited By

[`NEFilterSocketFlow`](/documentation/NetworkExtension/NEFilterSocketFlow)

[`NEFilterBrowserFlow`](/documentation/NetworkExtension/NEFilterBrowserFlow)

### Inherits From

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

---

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