তথ্য প্রযুক্তি
- তথ্য প্রযুক্তি | NCTB BOOK
1.
What is the CPU of computer?
2.
What do you understand by software?
Software is a set of instructions, data or programs used to operate computers and execute specific tasks. It is the opposite of hardware, which describes the physical aspects of a computer. Software is a generic term used to refer to applications, scripts and programs that run on a device.
3.
Give the difference between data and information.
4.
What do you understand by VSAT?
5.
What is a transformer?
6.
Give the differences between IPS and UPS.
Characteristic | IPS (Intrusion Prevention System) | UPS (Uninterruptible Power Supply) |
---|---|---|
Purpose | Network security | Electrical power backup |
Functionality | Monitors network traffic for threats, identifies, and blocks them | Provides backup power during electrical outages, surges, or fluctuations |
Usage | Protects against unauthorized access, cyberattacks, and malicious activities | Safeguards electronic equipment from power-related issues |
Deployment | Typically deployed at network boundaries or within network segments | Installed between electrical outlet and connected equipment |
Examples | Cisco Firepower, Snort, Palo Alto Networks' Threat Prevention | APC, CyberPower, Eaton, etc. |
7.
Distinguish between saynchronous and synchronous counters.
The following table highlights the major differences between Synchronous and Asynchronous Counters.
Key | Synchronous Counter | Asynchronous Counter |
---|---|---|
Trigger | In case of Synchronous Counters, all the constituent flip-flops are triggered with same clock simultaneously. | In case of Asynchronous Counters, there is triggering of different flip-flops with different clock. |
Operation Speed | Operation speed of a synchronous counter is faster as compared to that of an asynchronous counter. | The operation speed of an asynchronous counter is comparatively slower than a synchronous counter. |
Error Prone | Synchronous Counters are less error-prone; they hardly produce any decoding errors because each flip-flop is individually clocked. | Asynchronous Counters are more error-prone and produce decoding errors in the system. |
Complexity | All the flip-flops in a synchronous counter coordinate with the clock, hence its design and implementation is complex as compared to that of an asynchronous counter. | In an asynchronous counter, the output of one flip-flop acts as the input of the next flip-flop, hence its design and implementation is quite simple. |
Sequence | A Synchronous counter can be operated in any desired count sequence, as it could get manipulated by changing the clock sequence. | An Asynchronous counter can operate only in a fixed count sequence, i.e., UP and DOWN. |
Delay | There is no propagation delay observed in case of Synchronous Counters. | In case of asynchronous counters, there is a subsequent propagation delay from one flip-flop to another. |
Conclusion
All the flip-flops in a synchronous counter are clocked simultaneously with the same clock input. In contrast, the constituent flip-flops of an asynchronous counter are clocked with different input signals at different instants of time.
8.
Classify computer memories and give their characteristics.
Primary Memory (Main Memory):
RAM (Random Access Memory): RAM is volatile memory used for temporarily storing data that the CPU is currently working on. It allows for fast read and write operations but loses data when the computer is powered off. Characteristics include speed, volatility, and high capacity (measured in GBs).
ROM (Read-Only Memory): ROM is non-volatile memory that stores firmware or software instructions that are permanently written during manufacturing. It retains data even when the power is turned off. Characteristics include non-volatility and read-only access.
Secondary Memory (Storage Memory):
Hard Disk Drive (HDD): HDDs are non-volatile, magnetic storage devices that offer high-capacity storage at a relatively lower cost. They are slower than SSDs but are commonly used for long-term data storage.
Solid-State Drive (SSD): SSDs use NAND flash memory for non-volatile data storage. They are faster, more energy-efficient, and durable compared to HDDs. SSDs are commonly used as primary storage in modern computers.
Optical Drives: These include CD, DVD, and Blu-ray drives, used for reading and writing optical discs. They are slower for data access but are still used for archiving and media distribution.
USB Drives (Flash Drives): These are portable and non-volatile storage devices that use NAND flash memory. They are commonly used for data transfer and backup due to their small size and convenience.
Memory Cards: These small, portable storage devices are commonly used in cameras, smartphones, and other portable devices. They use NAND flash memory and come in various formats like SD, microSD, and CompactFlash.
Tertiary Memory:
- Magnetic Tapes: Although less common today, magnetic tapes were historically used for long-term archival storage due to their high capacity. They are sequential access devices and not suitable for fast retrieval.
Cache Memory:
- L1, L2, and L3 Cache: These are small, high-speed memory units located closer to the CPU cores. They store frequently accessed data and instructions to reduce CPU access times to main memory (RAM).
Virtual Memory:
- Virtual memory is a memory management technique that uses a portion of the secondary storage (usually HDD or SSD) to simulate additional RAM. It allows computers to run larger applications and processes that require more memory than physically available.
Registers:
- Registers are the smallest, fastest, and most expensive type of memory, located within the CPU. They store data and instructions directly used by the CPU during its operations.
9.
Give a brief description of system software and application software with examples of applications.
Both system software and application software are essentially required for using the computer. But they are completely different from each other in many aspects like programing languages, purposes, development processes, etc. The important differences between a system software and an application software are listed in the following table −
Parameter | System Software | Application Software |
---|---|---|
Definition | System Software is the type of software which is the interface between application software and system. | Application Software is the type of software which runs as per user request. It runs on the platform which is provide by system software. |
Development Language | In general, System software are developed using low-level language which is more compatible with the system hardware in order to interact with. | In case of Application software, high level language is used for their development as they are developed as some specific purpose software. |
Necessity | System software are essential for operating the computer hardware. Without these software, a computer even may not start or function properly. | Application software are not essential for the operation of the computer. These are installed as per the user’s requirements. |
Usage | System software is used for operating computer hardware. | Application software is used by user to perform specific task. |
Installation | System software are installed on the computer when operating system is installed. | Application software are installed according to user’s requirements. |
User interaction | System software are specific to system hardware, so less or no user interaction available in case of system software. | Users can interact with an application software with the help of a User Interface (UI). |
Dependency | System software can run independently. It provides platform for running application software. | An application software cannot run independently. It cannot run without the presence of system software. |
Examples | Examples of system software include operating systems, compilers, assemblers, debuggers, drivers, etc. | Examples of application software include word processors, web browsers, media players, etc. |
Conclusion
The most significant difference between a system software and an application software is that a system software operates on the machine-side and is essential for operating the computer hardware, while an application software operates on the user-side and performs a specific task as per the user’s instructions.
10.
Briefly describe the impacts of computer on society.
Computers and software have had significant impacts on society. They have become more open and hyperconnected, managing large amounts of personal data and shaping our society . However, technology can enable both societal harm and benefit, as seen in cases of fake news, hacking, and biased search results .Computers can perform tasks such as calculations, data processing, communication, multimedia playback, and more. They can be used for various purposes, including personal use, business operations, scientific research, entertainment, education, and more
11.
Briefly describe the functions of any three layers of the TCP/Ip protocol suite.
Layer 4: the transport layer, transfers data across a network and provides error-checking mechanisms and data flow controls.
Layer 3: the network layer, moves data into and through other networks.
Layer 2, the data link layer, handles problems that occur as a result of bit transmission errors.