1.3 PHYSICAL CONNECTION

 In this section, we are going to cover two types of physical connection, namely Serial Transmission and Parallel Transmission.

1.3.1 Serial Transmission

In data communication, serial transmission (Figure 2 (a) refers to the sequential transmission of signal and data. The bits are sent sequentially over a single line. It is because serial transmission requires less signal processing and it is less prone to error than parallel transmission of data or signal. The serial transmission is preferred for longer distance transmission of data as a check digit or parity bit can be sent along it easily.



1.3.2 Parallel Transmission

In data communication, parallel transmission (Figure 2(b)) refers to simultaneous transmission of the signal or data. The bits are sent separately through different paths simultaneously. For parallel transmission it requires multiple electrical wires for transmitting multiple bits simultaneously. Transmission of multiple bits simultaneously leads to higher data transfer rates than serial transmission. In parallel data transmission, electrical wires are less reliable for long distances because of error and corrupt transmissions.



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