SecretKey deskey = new SecretKeySpec(key, "DES");
Cipher c1 = Cipher.getInstance (Algorithm);
IvParameterSpec ivSpec = new IvParameterSpec (bytes);
c1.init (Cipher.ENCRYPT_MODE, deskey, ivSpec);
byte[] cipherByte=c1.doFinal(plan_text.getBytes())
What does IvParameterSpec do?