What is data compression and its types? what is lossy compression.
The way in which data is transferred from sender to receiver is called data communication mode. It defines the direction of flow of data between devices. It is also called directional mode.
What is Data Transmission? Data transmission is the transfer of data from one digital device to another. This transfer occurs via point-to-point data streams or channels. These channels may previously have been in the form of copper wires but are now much more likely to be part of a wireless network.
- Simplex: Data travels in one direction (from A to B). …
- Half-duplex: Data travels in one direction (from A to B) and then the other direction (from B to A) but not at the same time. …
- Full-duplex: Data can travel in both directions at the same time.
Data transmission can be rightly said to transfer the data between two devices using a transmission channel. It has mainly three types of data transmission such as simplex, half-duplex, and full-duplex.
In addition to external communication, data transmission also may be internally carried to a device. For example, the random access memory (RAM) or hard disk that sends data to a processor is also a form of data transmission.
- CPU issues read command.
- I/O module gets data from peripheral whilst CPU does other work.
- I/O module interrupts CPU.
- CPU requests data.
- I/O module transfers data.
A conversation between two people is an example of communication. Data communications refers to the sharing of a virtual message. Electronic communications, like emails and instant messages, as well as phone calls are examples of data communications.
Transmission means the transfer of data from the source to the destination. Communication is the process of sending and receiving data using a data cable that is connected externally.
Handshaking usually uses two additional hardware lines, one is called “strobe” and the other is called “acknowledge”. The sender provides the signal to the strobe line and the receiver provides the signal to the acknowledge line. Handshaking can be used in both parallel data transfer and serial data transfer.
- Programmed I/O. The programmed I/O method controls the transfer of data between connected devices and the computer. …
- Interrupt-Based I/O. The interrupt-based I/O method controls the data transfer activity to and from connected I/O devices. …
- Direct Memory Access (DMA) I/O. …
- Channel I/O.
Data communication refers to the exchange of data between a source and a receiver via form of transmission media such as a wire cable. … Data can exist in a variety of forms such as numbers, text, bits and bytes. The Figure is an illustration of a simple data communication system.
Data Communication is a process of exchanging data or information. In case of computer networks this exchange is done between two devices over a transmission medium. This process involves a communication system which is made up of hardware and software.
Communication is the act of giving, receiving, and sharing information — in other words, talking or writing, and listening or reading. Good communicators listen carefully, speak or write clearly, and respect different opinions.
These are sender, receiver, communication medium, the message to be communicated, and certain rules called protocols to be followed during communication. The communication media is also called transmission media. Figure 11.2 shows the role of these five components in data communication.
In two-way communication, whenever a frame is received, the receiver waits and does not send the control frame (acknowledgment or ACK) back to the sender immediately. … This technique of temporarily delaying the acknowledgment so that it can be hooked with next outgoing data frame is known as piggybacking.
In computer or memory technology, a strobe is a signal that is sent that validates data or other signals on adjacent parallel lines. In memory technology, the CAS (column address strobe) and RAS ( row address strobe ) signals are used to tell a dynamic RAM that an address is a column or row address.
Signals transmitted back and forth over a communications network in order to establish a valid connection between two stations. … A “software handshake” sends codes such as “synchronize” (SYN) and “acknowledge” (ACK) in a TCP/IP transmission.
In telecommunications, asynchronous communication is transmission of data, generally without the use of an external clock signal, where data can be transmitted intermittently rather than in a steady stream.
Depending on their applications, I/O operations can be divided into three groups: sensory input, control output, and data transfer. Once the nature of each type of I/O operation is understood, the hardware design and software for these operations can be understood easily.
There are three principal I/O techniques: programmed I/O, in which I/O occurs under he direct and continuous control of the program requesting the I/O operation; interrupt-driven I/O, in which a program issues an I/O command and then continues to execute, until it is interrupted by the I/O hardware to signal the end of …
- CD-R/RW, DVD, and Blu-ray drive.
- Digital camera.
- Fax machine.
- Floppy diskette drive.
- Hard drives.
- NIC (network interface card)
- SD Card.
All in all, data communication allows businesses to reduce expenses and improve efficiency by sharing data and common equipment among many different computers. At the same time, the network may be connected through cables, telephone lines, infrared beams, which is cheaper and helps to reduce the expenses.
Data transmission and data reception or, more broadly, data communication or digital communications is the transfer and reception of data in the form of a digital bitstream or a digitized analog signal over a point-to-point or point-to-multipoint communication channel. …
As you can see, there are at least 6 distinct types of communication: non-verbal, verbal-oral-face-to-face, verbal-oral-distance, verbal-written, formal and informal types of communication.