Test: Networking and Multimedia- 2 - Class 10 MCQ

Software:
- Software refers to a collection of programs, data, and instructions that enable a computer system to perform specific tasks or functions.
- It is a set of instructions that tells the computer what to do and how to do it.
- It can be categorized into system software and application software.
Option B: Firewalls
- Firewalls are software programs or applications that monitor and control incoming and outgoing network traffic based on predetermined security rules.
- They act as a barrier between a trusted internal network and an untrusted external network, providing protection against unauthorized access and threats.
- Firewalls can be installed on individual computers or network devices such as routers or dedicated firewall appliances.
Explanation:
- Among the given options, firewalls are the software that is used to protect computer networks from unauthorized access and threats.
- Routers (Option A), gateways (Option C), and modems (Option D) are hardware devices that are used for network connectivity and data transmission, but they do not fall under the category of software.
- Firewalls, on the other hand, are software programs that are installed on computers or network devices to provide security and control over network traffic.
- Therefore, the correct answer is Option B: Firewalls.

Layer one of the OSI model is the Physical layer.
The Physical layer is responsible for the actual transmission of data bits over a physical medium. It deals with the physical characteristics of the communication medium and the electrical, mechanical, and functional specifications of the devices used to transmit data.
Key points about the Physical layer:
- It is the lowest layer in the OSI model and is concerned with the physical transmission of data.
- The Physical layer defines the physical and electrical properties of the transmission medium, such as cables, connectors, and signaling methods.
- It handles the conversion of digital data into a physical signal for transmission and vice versa.
- It defines the protocols for data encoding, modulation, and synchronization.
- It deals with the transmission of raw bits and does not concern itself with the content or structure of the data being transmitted.
- It ensures that the data is sent and received reliably, without errors or loss.
- Examples of devices that operate at the Physical layer include network interface cards (NICs), cables, hubs, repeaters, and modems.
- The Physical layer provides the foundation for higher layers in the OSI model to transmit data.
In summary, the Physical layer is responsible for the physical transmission of data and defines the specifications of the transmission medium and devices used for communication. It is the first layer in the OSI model and plays a crucial role in ensuring reliable data transmission.

The process of converting analog signals into digital signals so that they can be processed by a receiving computer is referred to as:

Answer: D. Digitizing

Explanation:
To provide a detailed solution, let's break down the process of converting analog signals into digital signals and explain each step:
1. Analog Signals:
- Analog signals are continuous waveforms that represent real-world data such as sound, temperature, or light intensity.
- These signals have infinite possibilities and can take any value within a specific range.
2. Digital Signals:
- Digital signals are discrete and binary in nature, consisting of only two possible values: 0 and 1.
- These signals are used by computers and digital devices to represent and process information.
3. Process of Conversion:
- The process of converting analog signals into digital signals involves several steps:
a. Sampling:
- The analog signal is sampled at regular intervals to capture its amplitude at each point in time.
- The sampling rate determines the number of samples taken per second, also known as the sample rate.
b. Quantization:
- Each sampled value is quantized by assigning it a specific digital value from a predefined range.
- This process reduces the infinite possibilities of the analog signal to a finite number of digital values.
- The number of digital values available is determined by the bit depth or resolution.
c. Encoding:
- The quantized digital values are encoded into binary code, usually represented as a series of 0s and 1s.
- This encoding allows the digital signal to be transmitted or stored in a format that computers can process.
d. Transmission:
- The digital signal can now be transmitted over various communication channels such as cables, fiber optics, or wireless networks.
- The binary representation of the signal ensures accurate and reliable transmission.
e. Reception and Decoding:
- The receiving computer or device receives the digital signal and decodes it back into quantized values.
- The decoding process reverses the encoding and quantization steps, reconstructing the original analog signal.
f. Processing:
- Once the analog signal is converted back to digital form, the receiving computer can process it using various algorithms and techniques.
- Digital signal processing (DSP) techniques can be applied to manipulate, analyze, or extract information from the digital signal.
Conclusion:
- The entire process of converting analog signals into digital signals, including sampling, quantization, encoding, transmission, reception, decoding, and processing, is collectively known as digitizing.
- Therefore, the correct answer to the given question is D. Digitizing.

Routing in OSI Network Architecture

Answer: B. Data link layer

Explanation:

The OSI (Open Systems Interconnection) model is a conceptual framework that standardizes the functions of a communication system into seven different layers. The routing process, which involves the selection of the best path for data packets to travel from the source to the destination, is primarily performed by the network layer in the OSI model. However, the data link layer also plays a role in routing by facilitating the transmission of data between directly connected nodes or devices. Here's a breakdown of the routing process in the OSI model:

1. Network Layer:

• The network layer is responsible for logical addressing, routing, and path determination.


• It receives data from the transport layer and adds network layer headers to create packets.


• It determines the best path for packet transmission based on the destination address and network conditions.


• It uses routing protocols (such as OSPF, RIP, BGP) to exchange routing information and build routing tables.


• It forwards packets to the next hop or the next network based on the routing table.

2. Data Link Layer:

• The data link layer provides reliable point-to-point communication between directly connected nodes.


• It encapsulates the network layer packets into data frames and adds data link layer headers and trailers.


• It performs error detection and correction using techniques like CRC (Cyclic Redundancy Check).


• It controls the flow of data between devices to avoid congestion.


• It uses MAC (Media Access Control) addresses to identify devices on the same network.


• It performs local network routing by forwarding data frames to the appropriate device based on MAC addresses.

While the primary responsibility of routing lies with the network layer, the data link layer contributes to the routing process by facilitating communication between directly connected devices. Therefore, in the OSI network architecture, routing is performed by both the network layer and the data link layer.

Answer:
Gateway is used to communicate between different networks. It acts as a bridge or translator between two different networks, allowing them to exchange data and communicate with each other.
Here is a detailed explanation:
What is a Gateway?
A gateway is a networking device that connects two or more networks together and facilitates communication between them. It serves as an entry or exit point for data traffic between different networks, allowing them to exchange information.
Function of a Gateway:
The main function of a gateway is to perform protocol conversion and data translation between different networks. It enables communication between networks that use different protocols, such as TCP/IP, Ethernet, or ATM.
Types of Gateways:
There are different types of gateways, including:
1. Network Gateway: Connects different types of networks, such as LAN (Local Area Network) and WAN (Wide Area Network).
2. Protocol Gateway: Translates data between different protocols, such as converting data from TCP/IP to IPX/SPX.
3. Application Gateway: Enables communication between different applications or services running on different networks.
4. Security Gateway: Provides security features such as firewall and VPN (Virtual Private Network) to protect the network from unauthorized access.
Advantages of using a Gateway:
1. Interoperability: Gateway allows different networks to communicate and exchange data seamlessly.
2. Protocol Conversion: It enables data translation between networks that use different protocols.
3. Security: Gateways can provide security features to protect the network from external threats.
4. Scalability: Gateways can be easily added or upgraded to accommodate the growing needs of the network.
In conclusion, a Gateway is used to communicate between different networks by acting as a bridge and facilitating data exchange between them. It plays a crucial role in enabling interoperability and ensuring smooth communication between networks that use different protocols.

Answer:
802.5 is the correct answer because it provides for a collision-free protocol. Here's a detailed explanation:
802 Standards:
The 802 standards are a set of networking protocols defined by the Institute of Electrical and Electronics Engineers (IEEE). These standards define the specifications for various aspects of network communication, including data link layer protocols, physical layer specifications, and network management.
Collision:
In networking, a collision occurs when two or more devices on a network attempt to transmit data at the same time, resulting in a garbled signal. Collisions can cause data loss and network congestion, leading to decreased performance.
802.2:
- Also known as the Logical Link Control (LLC) standard.
- Defines the interface between the Media Access Control (MAC) sublayer and the network layer.
- It does not provide a collision-free protocol.
802.3:
- Also known as Ethernet.
- Defines the CSMA/CD (Carrier Sense Multiple Access with Collision Detection) protocol.
- CSMA/CD allows devices to detect collisions and handle them by retransmitting the data.
- It does not provide a collision-free protocol.
802.5:
- Also known as Token Ring.
- Defines a token passing protocol, where a token is passed between devices to control access to the network.
- Only the device holding the token can transmit data, ensuring a collision-free protocol.
- It provides a collision-free protocol.
802.6:
- Also known as Distributed Queue Dual Bus (DQDB).
- Defines a protocol for metropolitan area networks (MANs).
- It does not provide a collision-free protocol.
Therefore, the correct answer is 802.5 as it provides for a collision-free protocol.

Number of Hosts That Can Successfully Send Data Simultaneously on Ethernet
There are certain limitations to the number of hosts that can successfully send data simultaneously on Ethernet. The answer to this question is:
Answer: B. 2
Explanation:
Ethernet is a widely used technology for local area networks (LANs) and it uses a shared medium for communication. The number of hosts that can send data simultaneously on Ethernet is limited due to the following reasons:
1. Collision Domain: In Ethernet, all devices connected to the same network segment share the same collision domain. A collision occurs when two or more devices transmit data at the same time, resulting in data corruption. To avoid collisions, Ethernet uses a carrier sense multiple access with collision detection (CSMA/CD) mechanism. This means that only one device can successfully transmit data at a time, while others must wait for their turn.
2. Half-Duplex Mode: Ethernet operates in either half-duplex or full-duplex mode. In half-duplex mode, a device can either transmit or receive data at a given time, but not both simultaneously. Therefore, only two hosts can communicate at the same time - one sending and the other receiving.
3. Bandwidth Sharing: Ethernet shares the available bandwidth among all the connected devices. If multiple hosts try to transmit data simultaneously, the available bandwidth gets divided, resulting in lower throughput for each host. To ensure efficient data transmission, it is recommended to limit the number of hosts sending data simultaneously.
In summary, due to the collision domain, half-duplex mode, and bandwidth sharing, Ethernet allows only two hosts to successfully send data simultaneously.

ARP (Address Resolution Protocol) is:
- A TCP/IP protocol used to dynamically bind a high level IP address to a low-level physical hardware address:
- ARP is a protocol used in TCP/IP networks to map an IP address to a corresponding physical MAC address.
- It allows devices on a local network to communicate with each other using their hardware addresses.
- ARP resolves IP addresses to MAC addresses on the same network segment.
- A TCP/IP high-level protocol for transferring files from one machine to another:
- This statement is incorrect. ARP is not used for file transfer; it is specifically used for address resolution.
- A protocol used to monitor computers:
- This statement is incorrect. ARP is not used for monitoring computers. It is solely used for address resolution.
- A protocol that handles error and control messages:
- This statement is incorrect. ARP is not responsible for handling error and control messages. It is solely used for address resolution.
Conclusion:
The correct answer is A: A TCP/IP protocol used to dynamically bind a high-level IP address to a low-level physical hardware address. ARP is essential for communication within a local network, allowing devices to find each other using their IP and MAC addresses.

UDP (User Datagram Protocol) is:
UDP is a protocol used for transmitting data over the internet. It is a simple and lightweight protocol that operates at the transport layer of the TCP/IP model.
Connectionless:
- UDP is a connectionless protocol, which means that it does not establish a dedicated connection between the sender and receiver before transmitting data.
- Each UDP packet, also known as a datagram, is independent and can be sent without prior setup or negotiation.
- This makes UDP faster and more efficient than connection-oriented protocols like TCP, as there is no need to establish and tear down connections.
Message Oriented:
- UDP is a message-oriented protocol, which means that data is sent in discrete chunks called datagrams.
- Each datagram is self-contained and carries its own source and destination addresses.
- UDP treats each datagram as an individual message and does not guarantee the order or delivery of these messages.
Advantages of UDP:
- Low latency: UDP has lower overhead and does not require the same level of error-checking and retransmission as TCP, making it ideal for real-time applications like video streaming or online gaming.
- Broadcast and multicast support: UDP allows for the broadcasting of data to multiple recipients simultaneously, making it useful for applications that require one-to-many communication.
- Lightweight: UDP has a smaller header size compared to TCP, making it more efficient for transmitting small amounts of data.
Disadvantages of UDP:
- Lack of reliability: UDP does not provide reliability mechanisms such as acknowledgments or retransmissions, so data may be lost or arrive out of order.
- No congestion control: UDP does not have built-in congestion control mechanisms, so it can potentially overwhelm a network if not properly managed.
- No flow control: UDP does not regulate the rate at which data is sent, which can lead to packet loss if the receiver cannot keep up with the sender's speed.
In conclusion, UDP is a connectionless and message-oriented protocol that offers low latency and is suitable for real-time applications. However, it lacks reliability and congestion control mechanisms, making it less suitable for applications that require guaranteed delivery.

The answer is B: Dynamic Host Configuration Protocol.
Explanation:
DHCP stands for Dynamic Host Configuration Protocol. It is a network management protocol used to automatically assign IP addresses and other network configuration parameters to devices on a network.
Here is a detailed explanation of DHCP:
1. Dynamic: DHCP dynamically assigns IP addresses to devices on a network. This means that IP addresses are not manually configured on each device but are automatically assigned by the DHCP server.
2. Host: DHCP is used to assign IP addresses to hosts or devices on a network. Hosts can include computers, smartphones, printers, routers, and other network devices.
3. Configuration: DHCP not only assigns IP addresses but also provides other network configuration parameters such as subnet mask, default gateway, DNS server addresses, and lease duration.
4. Protocol: DHCP is a protocol that defines the rules and procedures for devices to communicate and obtain network configuration information from the DHCP server.
Benefits of DHCP:
- Simplifies network administration by automating IP address assignment.
- Reduces the chances of IP address conflicts.
- Allows easy reconfiguration of network settings without manual intervention.
- Supports dynamic allocation of IP addresses based on the availability in the DHCP pool.
- Provides centralized management and control of IP address assignments.
In conclusion, DHCP (Dynamic Host Configuration Protocol) is a network management protocol that dynamically assigns IP addresses and other network configuration parameters to devices on a network.

ATM is an example of Star topology.
Explanation:
- ATM stands for Asynchronous Transfer Mode, which is a high-speed networking technology used for transmitting data.
- It is a form of packet-switching, where data is divided into small packets and transmitted over a network.
- In a star topology, all devices are connected to a central hub or switch. Each device has its own dedicated connection to the hub.
- Similarly, in an ATM network, all devices are connected to a central switch known as the ATM switch.
- The ATM switch acts as the central hub, and all devices connected to it have their own dedicated connection.
- This allows for efficient data transmission and minimizes data collisions or delays that can occur in other network topologies.
- The star topology also provides easy scalability and fault tolerance, as adding or removing devices does not affect the entire network.
- Therefore, ATM is an example of the star topology as it utilizes a central switch to connect multiple devices in a dedicated manner.

Explanation:

127.0.0.1 is a loop-back address.

Here is a breakdown of the different types of IP addresses:

• Limited broadcast address: This is an address used to send a message to all devices on the local network. It is represented by the IP address 255.255.255.255.


• Direct broadcast address: This is an address used to send a message to all devices on a specific network. It is represented by the IP address with all host bits set to 1.


• Multicast address: This is an address used to send a message to a specific group of devices on a network. It is represented by a range of IP addresses.


• Loop-back address: This is a special address used to test network connectivity on a local device. It is represented by the IP address 127.0.0.1.

Therefore, the correct answer is D: Loop-back address.

Answer:

The network address prefixed by 1110 is a multicast address.

Explanation:

When an IP address is prefixed with 1110, it indicates that it is a multicast address. Multicast addresses are used for one-to-many communication, where a single packet is sent to multiple hosts at the same time. This is different from unicast addresses, which are used for one-to-one communication, and broadcast addresses, which are used for one-to-all communication.

Here's a breakdown of the options:

• Class A address: Class A addresses have a prefix of 0, indicating that the network address starts with 0. The prefix 1110 does not match this pattern, so it is not a Class A address.


• Multicast address: Multicast addresses have a prefix of 1110, indicating that the network address starts with 1110. The given address matches this pattern, so it is a multicast address.


• Class B address: Class B addresses have a prefix of 10, indicating that the network address starts with 10. The prefix 1110 does not match this pattern, so it is not a Class B address.


• Reserved address: Reserved addresses are special addresses that are reserved for specific purposes. The given address is not specified as a reserved address, so it is not a reserved address.

Therefore, the correct answer is option B: Multicast address.

Class of IP Address:
There are five classes of IP addresses, denoted by the letters A, B, C, D, and E. Each class has a different range of IP addresses and is used for different purposes. The total number of classes is therefore 5.
Explanation:
Here is a breakdown of the different IP address classes:
1. Class A: This class is used for large networks and has a range of IP addresses from 1.0.0.0 to 126.0.0.0. The first octet in the IP address is reserved for the network ID, and the remaining three octets are used for host addresses.
2. Class B: This class is used for medium-sized networks and has a range of IP addresses from 128.0.0.0 to 191.255.0.0. The first two octets in the IP address are reserved for the network ID, and the remaining two octets are used for host addresses.
3. Class C: This class is used for small networks and has a range of IP addresses from 192.0.0.0 to 223.255.255.0. The first three octets in the IP address are reserved for the network ID, and the remaining octet is used for host addresses.
4. Class D: This class is used for multicast addresses and has a range of IP addresses from 224.0.0.0 to 239.255.255.255. These addresses are used for group communication and are not assigned to individual hosts.
5. Class E: This class is reserved for experimental purposes and has a range of IP addresses from 240.0.0.0 to 255.255.255.255. These addresses are not used in general networking.
Therefore, the total number of classes of IP addresses is 5.

Hardware that calculates CRC(Cyclic Redundancy Check) uses:

The hardware that calculates CRC (Cyclic Redundancy Check) uses the following components:

Shift Register:

• One of the primary components used in CRC calculation hardware is the shift register.


• A shift register is a digital circuit that can shift its stored bits either to the left or right, based on clock pulses.


• It is used to perform the polynomial division required in CRC calculations.

XOR Unit:

• Another important component used in CRC calculation hardware is the XOR (Exclusive OR) unit.


• The XOR unit performs the XOR operation on the input data and the feedback data in each stage of the shift register.


• This operation is necessary to generate the remainder bits in the CRC calculation process.

Both (a) and (b):

• The hardware used for CRC calculation combines the shift register and XOR unit to perform the required polynomial division and generate the CRC remainder bits.


• Both the shift register and XOR unit work together to calculate the CRC value.


• Hence, the correct answer is option C: Both (a) and (b).

Instruction Register:

• The instruction register is not directly involved in the CRC calculation process.


• It is a component used in a processor to hold the current instruction being executed.


• It is not related to the hardware used specifically for CRC calculation.

In conclusion, the hardware that calculates CRC (Cyclic Redundancy Check) uses a shift register and XOR unit in combination to perform the necessary polynomial division and generate the CRC remainder bits. The correct answer is option C: Both (a) and (b).