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Network / DTLS / earlyDataEnabled(_:)

Contents

Declaration
Parameters
Discussion

earlyDataEnabled(_:)

Enable early data (0-RTT) for DTLS.

Declaration

func earlyDataEnabled(_ enabled: Bool) -> DTLS

Parameters

enabled:
True to enable early data, false otherwise.

Discussion

warning:

This may have security implications for application data. In particular, DTLS early data is replayable by a network attacker. You must account for this when sending data before the handshake is confirmed. See RFC 8446 for more information. You MUST NOT enable fast open without a specific application profile that defines its use.

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NetworkInstance Method

iOS 27.0+iPadOS 27.0+Mac Catalyst 27.0+macOS 27.0+tvOS 27.0+visionOS 27.0+watchOS 27.0+

Declaration
Parameters
Discussion

Built on 2026-08-05 · Snapshot snapshot-20260805-beta.2 (macOS 27.0) · Commit 4bc0d8f · by @g-cqd · based on Apple Developer Documentation