同步传输：
在同步传输中，数据以块或帧的形式发送。这种传输是全双工类型。发送方和接收方之间的同步是强制性的。在同步传输中，数据之间不存在间隙。传输大量数据比异步传输更高效、更可靠。
异步传输：
在异步传输中，数据以字节或字符的形式发送。这种传输是半双工类型的传输。在该传输中，起始位和停止位被添加数据。它不需要同步。
现在，让我们看看同步和异步传输之间的区别：
| S.NO | Synchronous Transmission | Asynchronous Transmission |
|---|---|---|
| 1. | In Synchronous transmission, Data is sent in form of blocks or frames. | In asynchronous transmission, Data is sent in form of byte or character. |
| 2. | Synchronous transmission is fast. | Asynchronous transmission is slow. |
| 3. | Synchronous transmission is costly. | Asynchronous transmission is economical. |
| 4. | In Synchronous transmission, time interval of transmission is constant. | In asynchronous transmission, time interval of transmission is not constant, it is random. |
| 5. | In Synchronous transmission, There is no gap present between data. | In asynchronous transmission, There is present gap between data. |
| 6. | Efficient use of transmission line is done in synchronous transmission. | While in asynchronous transmission, transmission line remains empty during gap in character transmission. |
| 7. | Synchronous transmission needs precisely synchronized clocks for the information of new bytes. | Asynchronous transmission have no need of synchronized clocks as parity bit is used in this transmission for information of new bytes. |