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# authenticationMethod

The method used to authenticate the device with the IPSec server. For IKE version 2, when using extended authentication, this authentication method only affects how the client validates the authentication payload presented by the server.

```
var authenticationMethod: NEVPNIKEAuthenticationMethod { get set }
```

## Discussion

If this property is set to `NEVPNIKEAuthenticationMethodNone`, extended authentication will still be negotiated if [`useExtendedAuthentication`](/documentation/NetworkExtension/NEVPNProtocolIPSec/useExtendedAuthentication) is set to <doc://com.apple.documentation/documentation/Swift/true>.

---

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