    @Test(expected = IllegalArgumentException.class)
    public void authorizedKeysDecoderInvalidKeyType() throws GeneralSecurityException {

        // given
        String ed25519Str = "AAAAC3NzaC1lZDI1NTE5AAAAICIvyX9C+u3KZmJ8x4DuqJg1iAKOPObCgkX9plrvu29R";
        // when
        instance.decodePublicKey(ed25519Str);
    }