If information hasn't been encrypted in transmission, it will be easily caught, juggled, fabricated or repeat attacked etc, so its secrecy cann't be guaranteed.
信息在传输过程中如果不经加密，将很容易受到截取、篡改、伪造、重发攻击等威胁，其隐秘性也无从保障。
2
In this paper, a part repeat ARO error control system of combined continuous transmission pattern with SW ARQ pattern is considered.