private AlgorithmParameterSpec buildParameterSpec(final int encryptionKeySize) {
        val iv = new byte[encryptionSecretKey.length];
        if (encryptionKeySize > MINIMUM_ENCRYPTION_KEY_LENGTH) {
            System.arraycopy(this.encryptionSecretKey, 0, iv, 0, encryptionSecretKey.length);
            return new GCMParameterSpec(GCM_TAG_LENGTH, iv);
        }
        return new IvParameterSpec(iv);
    }
Secret key IV algorithm. Default is {@code AES}.
core/cas-server-core-util-api/src/main/java/org/apereo/cas/util/cipher/BaseBinaryCipherExecutor.java