# AccessoryTransportSession A class that manages a transport session between the extension and the system. ``` class AccessoryTransportSession ``` ## Overview The [`AccessoryTransportAppExtension`](/documentation/AccessoryTransportExtension/AccessoryTransportAppExtension) protocol’s [`accept(sessionRequest:)`](/documentation/AccessoryTransportExtension/AccessoryTransportAppExtension/accept(sessionRequest:)) method receives a [`AccessoryTransportSession.Request`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/Request) object containing an instance of this class. ## Topics ### Managing session requests [`class Request`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/Request) An incoming session request that your extension accepts or rejects. ### Handling session events [`protocol EventHandler`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/EventHandler) A protocol that defines methods for handling transport session events. [`enum DataEvent`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/DataEvent) An enumeration of data events that the transport extension receives. ### Managing the session life cycle [`func cancel(error: AccessoryTransportSession.Error?)`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/cancel(error:)) Cancels the session. ### Accessing session properties [`var description: String`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/description) A string that describes the transport session. ### Sending data [`func sendMessageToDataProvider(TransportMessage) throws(AccessoryTransportSession.Error)`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/sendMessageToDataProvider(_:)) Sends a message to the data provider extension. ### Creating feature sessions [`func makeFeatureSession(() -> H) throws(AccessoryTransportSession.Error) -> H.Session`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/makeFeatureSession(_:)) Creates a feature session for the provided handler. ### Handling errors [`enum Error`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/Error) Errors that can occur with an accessory transport session. ### Determining the communication method [`var transport: AccessoryTransport?`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/transport) A transport method that the session uses to communicate with the accessory. [`var transportStateRestoreIdentifier: String?`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/transportStateRestoreIdentifier) An optional identifier for restoring transport state across sessions. [`var pushToken: Data?`](/documentation/AccessoryTransportExtension/AccessoryTransportSession/pushToken) A token that identifies the iOS device to the Apple Push Notification service for routing accessory responses over the internet. ## Relationships ### Conforms To [`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)