All kinds of data communication require some copper circuit boards, wires, or electrical conductors. These conductors use a current or voltage combination to represent bits (binary digits). But how does this process actually work? Let’s first discuss what Data transmission is.
What is Data Transmission?
It refers to how to devices or any components within the computer communicate with each other. This communication takes place through the transmission of signals between two digital devices through a transmission medium. This transmission of the signal may be in analog format or digital format.
Analog Transmission of Data: An analog transmission of data is in the form of a continuous wave characterized by frequency and amplitude.
Digital Transmission of Data: A digital transmission of data is in the form of a binary transmission made up of a sequence of pulses in the form of 1 and 0.
Data that is to be transmitted is converted into appropriate formats for transmission. The transmission of data concerning time and space is highly dependent on the medium of transmission.
The medium of transmission between two devices is further characterized as:
- Guided Medium – Wired or bounded transmission media, e.g., Cables (Twisted Pair Cable, Coaxial Cable, and Optical Fiber Cable)
- Un-Guided Medium – Wireless or unbounded transmission media, e.g., Microwaves, Radio waves, and Infrared waves.
The medium that is selected for the transmission defines how fast the data may travel. How much the data can travel and in what mode the data will be transmitted.
The data in a computer is transmitted in binary signals (i.e., 1 and 0). Hence, it is also known as the Digital Transmission of data. Whether in a guided medium or unguided medium, the transmission uses combinations of voltage, current, and/or time to represent binary digits. E.g., a voltage may be defined as either “High” or “Low” now, we may assign each of these values a particular Bit (1 or 0) let’s suppose “High = 1” and “Low = 0” then each time a voltage fluctuates the digital signal may either have the value 1 or 0.
How is the data transmitted through wires in computers?
We have already established how a computer uses digital data transmission for communication, and these digital signals are composed of either 1 or 0. But how actually these 1 and 0 travels through the wires? And most importantly, how are these 1 and 0 translated into the actual intended message/command?
We will begin by answering the third question: How are 1 and 0 actually translated into a message/command. To transfer data, it is important to change any form of instruction or command given to or given by the computer into a binary form. This process is achieved by first converting a text into its ASCII code. ASCII code is abbreviated from American Standard Code for Information Interchange, a character encoding standard for electronic communication. Once the ASCII value of the text is achieved, that value is then converted into binary code. When this message is received at the destination, it may again need to be translated into text. For this procedure, we may convert the given binary code into ASCII code and then into text. The binary code that is created may need further encryption techniques to transmit the data and communication medium securely. We may also apply a compression algorithm to save the bandwidth during data transmission.
Now we shall answer the first question of how actually the data is transferred in a computer. Suppose we transmit the number 6; this number is first translated into binary code “0000 0011” in an 8-bit binary encoding system. This binary code is then sent to a modem. A modem is a device that converts the binary data into analog data using some modulation techniques, e.g., pulse code modulation. This translation of digital signals into analog signals is important as the cables that transmit the data are only capable of transferring analog signals defined using voltage or current. We know that what flows through the cable is current, and a current may carry electrons. We also know that the term current and voltage come in a pair; the current is flowing because there is a voltage on the wire, and there is a conductive path from that voltage to a lower voltage. When a signal propagates along a wire, it’s actually the electromagnetic field between the wire and a nearby “ground” conductor propagating. So it is actually an electromagnetic wave transmitting and an electron that is carrying the signal along the wire. Now we may say that this analog signal will then travel through the wires and reach the destination. This data is again sent to a modem where the received analog signal is translated into a binary signal at the destination. The binary signal is converted into binary code and finally into the value 10.
Can the fast speed determine the amount of data that can be transmitted?
There is no doubt that it takes very little time for the electronic signals to travel through the wires. Electronic signals take about seventy to eighty percent of the speed of light. Although it takes less time, speed is still not a factor determining the amount of data you can transfer within a given time frame.
However, through data transmission, we can find out how much the process will be delayed—for example, the delay between when the data will be received and sent. The process can be described as a conveyor belt that takes a certain speed to travel through. Let’s suppose there is a conveyor belt, and it takes approximately one minute for the belt to travel from point 1 to 2. For instance, you place dollar bills on this belt at point 1, and the rate is 1 bill per second, it would take about one minute for you to see something point 2. But as soon as the conveyor belt starts to travel, you will receive dollar 1 every second. Let’s take this example further and imagine that instead of one bill, there is a stack of ten one-dollar bills at point 1, which will travel to point 2 at a rate of one stack per second. This means that in one minute, you will receive a dollar often every second. Over here, the speed of the belt is not changed. The same applies to data transmission.
You can easily transfer a movie in just a few minutes, even if you have a slow propagation connection with large bandwidth. However, you would have a delay of some seconds with the same connection if you are trying to voice call or video chat with someone.
People who use satellite internet often have this kind of experience. This is because the signals have to travel to space and come back, which is a long distance. This happens even if the bandwidth is large.
What role does the bandwidth play in data transmission?
The bandwidth has a lot to do with the amount of data that is sent. Commonly, we think of the bandwidth as just a term that can tell what amount of data we can send at a per-unit rate of time. However, we have never thought of why it is known as bandwidth.
It is known as bandwidth because the amount of data that we can transmit in a particular time has a lot to do with the width of the band in the allowed frequency spectrum. For example, if you can use a 100-200 MHz range, then you can transfer the data a lot faster than if you are using a 100-101 MHz allowed range.
The data transmission is done through radio waves, and the wire used is actually a waveguide, the same way a fiber optic cable works as a waveguide for infrared light.
Transmission wires let the data be transferred at such fast rates because they trap the radio signals and do not let them escape from the wires. They also do not let anything interfere with the outside sources.
If you are not using wires, you transmit the data in a common space, which means that every channel has to be in a separate spectrum region. The spectrum has to be carefully allocated to every different channel of data. Over here, a wire is very functional and is used to create a private space for every channel so that every channel can use large spectrum regions so that there is no interference from any other channel. As the wire uses a large spectrum region, it has a larger bandwidth. This means higher rates of data can be transferred.
Advantages and Disadvantages of Data Transmission through Wires
Everything is becoming wireless these days, and that is putting great emphasis on wireless data transmission. You may feel confused as to which option you should choose for optimum data transmission. Should it be wireless data transmission or data transmission? Often the fact that the wireless option sounds more tech-savvy would influence your decision. However, to make the right choice, you must evaluate data transmission’s pros and cons through wires.
Wires are more secure than wireless options. This means that transmitting data through wires will be more secure than choosing a wireless data transmission option. Even though wireless options do have passwords and security criteria, a process that includes wires is always better in terms of security.
As discussed earlier, the use of wires for data transmission helps prevent any outside interference or any interference caused by radio or electricity frequency. Such interference is known as radiofrequency or electromechanical interference. On the other hand, wireless options are more prone to interference caused by radiofrequency. Often people who chose wireless data transmission complain about problems caused by radiofrequency. However, a data transmission done with a wire does not cause this kind of problem.
A consistent connection is another big advantage of data transmission using a wire compared to wireless data transmission. People who have used wireless data transmission have often complained about an inconsistent connection. This inconsistency is caused by a lapse in the connection network, which further causes a lapse that is momentary in the electrical interference or wireless signal. This can refute a great amount of work, delay the transfer of data and also introduce you to data corruption levels which are unacceptable.
Hence, data transmission through wires lets you have a more consistent connection and does not cause any interruptions due to momentary lapses.
You can enjoy a great speed of data transmission when you use wires. However, you don’t need to enjoy a fast speed with all kinds of wires. If you are using those who can bear data rates up to ten gigabits, you can have comparatively higher speed. Such cables are meant for transmitting light and are optimal for higher speed.
When something has some pros, there have to be some cons. Mobility is one of the biggest cons of using wires for data transmission. When you are using a wireless network for data transmission, you can move about here and there without worrying about anything as there are no wires that could limit your movement. Although you can move about in a certain range, you are still free to and mobile. However, using wires limits mobility and is one of the biggest disadvantages.
When you are using wires to transmit data to more than one computer connection, you may need to connect a hub or router to the cabling network and then connect the devices to the router or hub first. A router or hub would support 255 devices.
A wireless network would be easier to set up as compared to wires. If you are using wires, then you will have to route and the wires and then terminate the wires properly at both sides. This could often involve finding space for wires to crawl, and if there is not enough space, you may have to drill holes in the interior of your walls and spaces around, which could be a little frustrating at times.
Is it possible to transmit and receive data through a single wire at the same time?
Data is transmitted and received through a single wire at the same time. A typical example is an undersea link that sends thousands of telephone calls simultaneously using a single wire. Usually, two methods are used. One is Time Division Multiplexing, and the other is Frequency Division Multiplexing. In the digital world, Time Division Multiplexing is well-known. In contrast, Frequency Division Multiplexing is famous in the analog method. Despite the difference, both can be used in all kinds of signals.
In Time Division Multiplexing, the given wire carries a single signal at one time. However, this may not feel like it is reaping the signal at the same time because the cable or wire is receiving and transmitting simultaneously. In other words, it is handling various signals at the same time. When this is done, the data is processed so fast compared to the rate of the data that it looks as if it is receiving and sending signals simultaneously. The method of Time Division Multiplexing is universal in today’s time as various protocols embody it. It is used for signaling, physically utilizing the internet and other networks.
On the other hand, Frequency Division Multiplexing transmits data at once as it uses subcarrier frequencies.