Difference between Serial and Parallel Transmission

Data transmission is the process of data delivery between two or multiple digital devices. The data is transmitted between digital systems using one of two methods: Serial or Parallel Transmission. They have some commonalities and some differences. The main distinction between these transmissions is that the data is transferred bit by bit in Serial Transmission. Still, in Parallel Transmission, the data is sent one byte (8 bits) or character at a time. The main similarity between these transmissions is that both transmissions are utilized to connect and interact with other devices. In addition, parallel transmission is time-sensitive, but serial transmission is not.

In this article, you will learn about the difference between Serial and Parallel Transmission. But before discussing the differences, you must know about Serial and Parallel Transmission with their advantages and disadvantages.

What is Serial Transmission?

In Serial transmission, the data is delivered bit by bit from one computer system to another via bi-directional where each bit has its own clock pulse rate. In Serial Transmission, 8 bits are transferred at a time, with a start and stop bit (i.e., referred to as a Parity bit), which are 0 and 1. In this transmission, serial data cables are utilized to send data across extended distances. In this transmission, the data is delivered in proper order. It is made out of a 9-pin cable with a D-shaped that links data in series.

Types of Serial Transmission

There are mainly two types of serial transmission. These are as follows:

1. Asynchronous Serial Transmission

Asynchronous transmission adds an extra bit to every byte to notify the recipient of the appearance of new data. Typically, the start bit is 0, and the stop bit is 1.

2. Synchronous Serial transmission

There is no extra bit added in synchronous transmission; rather, data is conveyed in the form of frames that comprise numerous bytes.

The serial transmission system cannot function without the installation of hardware at the transmitting and receiving ends. The hardware at the sending and receiving ends can transfer data from the device's parallel mode to serial mode.

Advantages and Disadvantages of the Serial Transmission

There are various advantages and disadvantages of Serial transmission. Some advantages and disadvantages of Serial transmission are as follows:

Advantages

1. It is very cost-effective.
2. It can be utilized for long-distance communication.
3. It is more reliable and stable than other transmissions.

Disadvantages

1. The transmission rate of data is low.
2. Its throughput depends on the bit rate.

What is Parallel Transmission?

Parallel Transmission involves the simultaneous transfer of numerous bits from one computer system to another. It is quicker to send the bits and is utilized for short distances. It is also advantageous because it conforms to the underlying hardware, as electronic equipment such as computers and communication systems employ parallel circuits inside. The parallel interface works well in conjunction with the internal hardware.

The installation and problem resolution are simple because it is placed in a single physical cable and utilizes a 25-pin port containing 17 signal lines and 8 ground lines. The 17 single lines are divided into 4 lines for initiating handshaking, 5 lines for communicating and notifying errors, and 8 for data transfer.

Advantages and Disadvantages of the Parallel Transmission

There are various advantages and disadvantages of Parallel transmission. Some advantages and disadvantages of Parallel transmission are as follows:

Advantages

1. It may transmit N bits simultaneously. A parallel interface can perform N times faster than a serial interface.
2. The data can be sent from a computer to a printer using the parallel transmission. The printer is connected to the computer's parallel port, and a parallel cable with numerous wires can connect the printer to the computer. It is a highly rapid way of data transport.
3. The data is transmitted significantly more quickly in parallel transmission.
4. It works well for short-distance communication.
5. The set of bits is transferred at the same time.

Disadvantages

1. Multiple communication channels are required in parallel transmission.
2. N communication lines must be utilized to transfer the data stream, and this n number of wires must be used.
3. It is costly, so it is usually confined to small distances.
4. The wire thickness must be raised to reduce signal loss when transmitting data over long distances.

Key Differences between Serial and Parallel Transmission

Here, you will learn about the key differences between Serial and Parallel Transmission. Some of the main differences between Serial and Parallel Transmission are as follows:

1. A serial transmission is a form of transmission where data is transferred from one end to the other using only one communication link. In contrast, the other type of transmission, known as parallel transmission, uses numerous parallel lines to send every bit of data concurrently.
2. A single line is needed for communication and data transfer in serial transmission. In contrast, numerous lines are needed for parallel transmission.
3. Parallel transmission is quicker as numerous lines are used to convey the data. On the other hand, a single cable is used for data transmission in serial transmission.
4. Serial Transmission is easy to use and reliable. On the other hand, Parallel Transmission is complex and unreliable.
5. Serial Transmission is suitable for long-distance transmission. On the other hand, Parallel Transmission is only suitable for short distances.
6. In a serial transmission system, various types of converters are necessary to transform data between internal parallel form and serial form. In contrast, converters in parallel transmission systems are not required.
7. Serial Transmission is slower. In contrast, Parallel Transmission is faster than Serial Transmission.
8. Serial transmission is full-duplex because the transmitter can both send and receive data. On the other hand, Parallel Transmission is half-duplex because data is either transmit or received.
9. As Serial Transmission utilizes a single link, it is simple to implement and does not require a large investment. It is inexpensive. On the other hand, Parallel Transmission necessitates the implementation of many links, making it's not cost-efficient.
10. One bit is sent to every clock pulse in serial transmission. In contrast, eight bits are sent at one clock pulse in Parallel Transmission.
11. Data (bits) flow bidirectional in serial transmission. In contrast, data flows in numerous lines in Parallel Transmission.

Head-to-head comparison between Serial and Parallel Transmission

Here, you will learn the head-to-head comparisons between Serial and Parallel Transmission. The main differences between Serial and Parallel Transmission are as follows:

Conclusion

Both serial and parallel transmission methods have benefits and downsides. Serial Transmission is more dependable for delivering data over greater distances. In contrast, Parallel transmission is mainly utilized for short distances and gives faster speeds. In summary, both transmissions are important for data transfer.