3.2 INPUT OUTPUT DEVICES

 The computer will be of no use if it is not communicating with the external world. Thus, a computer must have a system to receive information from the outside world and must be able to communicate results to the external world. For this purpose computer use input/output devices. Input and output devices can also be written as I/O devices.

Input and output devices of a computer system are the devices that connect you to computer. Input devices let you to transfer data and user command into the computer. Input devices technologies are rapidly developing and are used to interact with the computer system. For example, you can type in data by using a keyboard, or you can input data in picture form by using a scanner in computer system. Inputs are data or signals received by the computer system and outputs are the data and signals which are sent by it as result after processing the input.

The, output devices display the result of input data or signals after processing it. Examples of these could be your computer’s monitor, which displays all the programs which are running into the computer, as well as the printer, which will print out a hard copy of the information which is saved in your computer.

Input and output devices allow the computer system to interact with the outside world by moving data into and out of the system. An Input device is used to bring data into the system. Examples of some input devices are:

  • · Keyboard
  • · Mouse
  • · Joystick
  • · Microphone
  • · Bar code reader
  • · Graphics tablet

An output device is used to send data out of the system. Examples of some output devices are:

  • · Monitor
  • · Printer
  • · Plotter
  • · Speaker

Input and output devices in short are also called I/O devices. They are directly connected to an electronic module called I/O module or device controller. For example, the speakers of a multimedia computer system are directly connected to a device controller called an audio card which in turn is connected to the rest of the system.

Input and output devices are similar in operation but perform opposite functions. It is through the use of these devices that the computer is able to communicate with the outside world.

Input data for the computer system can be in any of the following forms:

  • · Manual inputs from a keyboard or console.
  • · Analog inputs from instruments or sensors.
  • · Inputs from a storage device, such as PenDrive, CD’s and Floppy Drives.

The speed of processor is more than the input devices, such as keyboard of computer system. Computer system can process hundreds or thousands of characters per second. Thus, a study of the first method i.e., manual input reflects the inability of human operated  keyboards or keypunches to supply data at a speed that matches the speed of digital computers.

Comments

Post a Comment

Popular posts from this blog

3.8 SECURE NETWORK DEVICES

 In this unit, we have already learnt that the firewall is only one entry point to your network. Modems, if you allow them to answer incoming calls, can provide an easy means for an attacker to sneak around, your front door (or, firewall). Just as castlesweren't built with moats only in the front, your network needs to be protected at all of its entry points. Secure Modems, DialBack Systems If modem access is to be provided, this should be guarded carefully. The terminal server, or network device that provides dialup access to your network needs to be actively administered, and its logs need to be examined for strange behavior. Its passwords need to be strong not ones that can be guessed. Accounts that aren't actively used should be disabled. In short, it's the easiest way to get into your network from remote: guard it carefully. There are some remote access systems which have the feature of a twopart procedure to establish a connection. The first part is the remote user di...
Read more

3.5 SECURITY ISSUES FOR SMALL AND MEDIUM SIZED BUSINESSES

 Small and medium sized businesses use the Internet and networked applications to reach new customers and serve their existing ones more effectively. At the same time, new security threats and legislation puts increased pressure on business networks to be reliable and secure. Business Challenges According to recent studies, security is the biggest challenge facing small and mediumsized businesses. Everchanging security threats from both inside and outside the business network can wreak havoc on business operations, affecting profitability and customer satisfaction. Small and mediumsized businesses must also comply with new regulations and laws created to protect consumer privacy and secure electronic information. Security issues for small and medium – sized businesses are classified into 5 basic categories: Worms and Viruses As per research, Computer worms and viruses remain the most common security threat, with 75 percent of small and medium businesses affected by it.. Worms and v...
Read more

3.6 TOOLS FOR NETWORK SECURITY

There are many strong tools available for securing a computer network. Tools to protect your enterprise network have been evolving for the last two decades, roughly the same amount of time that people have been trying to break into computer networks. These tools can protect a computer network at many levels, and a wellguarded enterprise deploys many different types of security technologies. The most obvious element of security is often times the most easily overlooked: physical security—namely, controlling access to the most sensitive components in your computer network, such as a network administration station or the server room. No amount of planning or expensive equipment will keep your network secure if unauthorized personnel can have access to central administration consoles. Even if a user does not have evil intent, an untrained user may unknowingly provide unauthorized outside access or override certain protective configurations. Let us briefly discuss few of these network secur...
Read more