---
title: "sendSecurityMessage(_:)"
framework: accessorytransportextension
role: symbol
role_heading: Instance Method
path: "accessorytransportextension/accessorysecuritysession/sendsecuritymessage(_:)"
---

# sendSecurityMessage(_:)

Sends a security message to the system.

## Declaration

```swift
func sendSecurityMessage(_ message: SecurityMessage) throws(AccessorySecuritySession.Error)
```

## Parameters

- `message`: A security message containing key material.

## Discussion

Discussion Use this method to initiate key exchange by sending a SecurityMessage with SecurityMessage.KeyType.publicKey. The system responds by calling your handler’s messageReceived(_:completion:) method with encapsulated key material.

## See Also

### Managing the session life cycle

- [cancel(error:)](accessorytransportextension/accessorysecuritysession/cancel(error:).md)