ios - iOS Vpn 连接

Question

NEVPNProtocolIKEv2 *sec = [[NEVPNProtocolIKEv2 alloc] init];

sec.serverAddress = @"domain.com";
sec.remoteIdentifier = @"domain.com";
sec.username = @"username";
sec.localIdentifier = @"username";
sec.authenticationMethod = NEVPNIKEAuthenticationMethodSharedSecret;

如何指定用户的密码？

服务器密码类型：EAP