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# MCSessionSendDataMode

Indicates whether delivery of data should be guaranteed.

```
enum MCSessionSendDataMode
```

## Topics

### Constants

[`MCSessionSendDataReliable`](/documentation/MultipeerConnectivity/MCSessionSendDataMode/reliable)

The framework should guarantee delivery of each message, enqueueing and retransmitting data as needed, and ensuring in-order delivery.

[`MCSessionSendDataUnreliable`](/documentation/MultipeerConnectivity/MCSessionSendDataMode/unreliable)

Messages to peers should be sent immediately without socket-level queueing. If a message cannot be sent immediately, it should be dropped. The order of messages is not guaranteed.

## Relationships

### Conforms To

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

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

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

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

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

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

---

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