Data TransmissionThe purpose of this report is to describe common data transmission terminology. This article will discuss various data transmission (communication) protocols and how they are used in data communication. Synchronous and asynchronous: Asynchronous serial transmission is a technique used in RS232 serial communication. The data is framed by a series of control bits called start bit, stop bit(s), parity bits, and error check bits. A transmission clock signal is used to synchronize data on the transmission line to the receiving end. At the receiver, a clock signal, called the receive clock, which corresponds to the transmit clock, is used to decode the transmitted data back to the original by removing the control bits. Synchronous transmission sends packets of data, unlike asynchronous transmission, which sends data one bit at a time. The data is surrounded by start and end frames. The start frame tells the receiver to synchronize its internal clock and wait for incoming packets. The end frame marks the end of the packet. Low-speed data transmission uses asynchronous transmission. Since asynchronous transmission does not include error checking, it is not very efficient. Synchronous transmission, on the other hand, is very efficient. Data is transmitted in blocks. Synchronous communication is well suited for high-speed data transmission. The protocol has error checking capabilities. Analog and digital: Analog signals represent a constantly changing signal, such as a sound wave emitted by a speaker or an alternating current (sine wave) flowing on a wire. The digital signal, on the other hand, is a digital representation of an analog signal, it is either off or on. AM – Amplitude Modulation and FM – Frequency modulations are means used to transmit an analog signal. DM – Digital modulation is used to transmit a digital signal (Analog vs Digital Transmission, 2005) . It works like this. A printer locally connected to the computer uses the X off control signal to inform the computer that the print buffer is full and should stop sending data. When the printer is ready to receive more data, the X on signal is sent to signal the computer to resume data transfer. Simplex and Duplex: Simplex transmission is used to transmit data in one direction only. It's like a one-way street for data. Duplex transmission means data is transmitted in both directions..