---
title: NWProtocolIP.ECN
framework: network
role: symbol
role_heading: Enumeration
path: network/nwprotocolip/ecn
---

# NWProtocolIP.ECN

Flag values for Explicit Congestion Notifications in IP packets.

## Declaration

```swift
enum ECN
```

## Topics

### ECN Flags

- [NWProtocolIP.ECN.nonECT](network/nwprotocolip/ecn/nonect.md)
- [NWProtocolIP.ECN.ect0](network/nwprotocolip/ecn/ect0.md)
- [NWProtocolIP.ECN.ect1](network/nwprotocolip/ecn/ect1.md)
- [NWProtocolIP.ECN.ce](network/nwprotocolip/ecn/ce.md)

## Relationships

### Conforms To

- [Equatable](swift/equatable.md)
- [Escapable](swift/escapable.md)
- [Hashable](swift/hashable.md)

## See Also

### Sending IP Options

- [init()](network/nwprotocolip/metadata/init().md)
- [ecn](network/nwprotocolip/metadata/ecn.md)
- [serviceClass](network/nwprotocolip/metadata/serviceclass.md)