Test: Computer Networking - Class 9 MCQ

Transmission Option for High Cost of Digging Land:
Using a transmission method that can be set up quickly and does not require extensive digging can be a cost-effective solution when the cost of digging the land for placing cables is high. Among the given options, the best choice would be Microwaves.
Reasons for choosing Microwaves:
1. No digging required: Microwaves can be transmitted through the air, eliminating the need for digging and laying cables underground. This helps in reducing the overall cost and time required for installation.
2. Fast setup time: Microwaves can be set up relatively quickly compared to other transmission methods. Once the necessary equipment is installed, the transmission can be established almost instantly, saving time and labor costs.
3. Wide coverage: Microwaves have a wide coverage area, allowing for long-distance transmission without the need for extensive infrastructure. This makes them suitable for connecting remote locations or areas where digging is expensive or not feasible.
4. Reliable performance: Microwaves provide reliable transmission with minimal interference. They can transmit data at high speeds and are commonly used for point-to-point communication, such as in telecommunications and broadcasting.
5. Cost-effective: Compared to other transmission methods like laying cables or setting up satellite links, using microwaves can be a more cost-effective solution, especially when the cost of digging the land is high.
In conclusion, if the cost of digging the land for placing cables is high, using microwaves as a transmission method can be a viable option. It offers quick setup time, wide coverage, reliable performance, and cost-effectiveness, making it suitable for various applications.

Answer:
The correct answer is D: Microwaves. Microwaves are not used for wired transmission. Here's a detailed explanation:
Wired Transmission:
Wired transmission refers to the transfer of data or information through physical cables or wires. It is commonly used for various purposes, including communication, networking, and data transfer. There are several types of cables used for wired transmission, including coaxial cables, optical fiber, and twisted pair cables.
Types of Cables used for Wired Transmission:
1. Coaxial Cables: Coaxial cables are widely used for wired transmission. They consist of an inner conductor surrounded by a dielectric insulator, a metallic shield, and an outer conductor. Coaxial cables are known for their high bandwidth and are commonly used in cable TV, internet connections, and CCTV systems.
2. Optical Fiber: Optical fiber is another commonly used cable for wired transmission. It uses light signals to transmit data through thin strands of glass or plastic fibers. Optical fiber cables offer high bandwidth, low signal loss, and are immune to electromagnetic interference. They are extensively used in long-distance communication networks, internet backbones, and high-speed data transmission.
3. Twisted Pair Cable: Twisted pair cables are a type of copper cable that consists of pairs of insulated wires twisted together. They are commonly used for telephone lines, computer networks, and Ethernet connections. Twisted pair cables are cost-effective and provide reliable data transmission over short to medium distances.
Microwaves:
Microwaves, on the other hand, are not used for wired transmission. They are a form of wireless transmission that uses electromagnetic waves with frequencies ranging from 300 MHz to 300 GHz. Microwaves are commonly used for wireless communication, such as microwave ovens, satellite communication, and wireless networks.
In summary, while coaxial cables, optical fiber, and twisted pair cables are used for wired transmission, microwaves are not. Microwaves are primarily used for wireless communication and are not directly associated with wired transmission methods.

The set of rules used for transmission of data over a network is called a Protocol.
Explanation:
- Protocol: It refers to a set of rules and procedures that govern the communication between devices on a network. It defines how data is formatted, transmitted, received, and interpreted across the network.
- LAN: Local Area Network (LAN) refers to a network that is confined to a small geographical area, such as a home, office, or building. While LANs may use protocols for data transmission, the set of rules itself is called a protocol.
- WAN: Wide Area Network (WAN) refers to a network that spans a large geographical area, such as multiple cities or even countries. Similar to LANs, WANs also use protocols for data transmission.
- Transmission Media: Transmission media refers to the physical channels or pathways through which data is transmitted over a network. While different transmission media may have their own specifications and protocols, the term "protocol" specifically refers to the set of rules governing data transmission.

Therefore, the correct answer is C: Protocol.

Protocols used for Internet Telephony:


1. VoIP (Voice over Internet Protocol):
- VoIP is a technology that allows voice communication over the internet.
- It converts voice signals into digital data packets and transmits them over the IP network.
- It is the primary protocol used for internet telephony.
2. SIP (Session Initiation Protocol):
- SIP is a signaling protocol used for initiating, modifying, and terminating real-time sessions involving voice, video, and messaging applications.
- It is widely used in VoIP systems to set up and control communication sessions.
3. H.323:
- H.323 is an ITU-T recommendation that defines a suite of protocols for multimedia communication over IP networks.
- It is used for voice, video, and data communication in IP-based networks.
- H.323 is widely used in video conferencing systems but can also be used for voice communication.
4. RTP (Real-time Transport Protocol):
- RTP is a protocol used for the transport of real-time media, such as audio and video, over IP networks.
- It provides mechanisms for timing reconstruction, loss detection, and jitter control.
- RTP is used in conjunction with other protocols like SIP or H.323 for internet telephony.
5. IAX (Inter-Asterisk eXchange):
- IAX is a protocol used by Asterisk, an open-source PBX (Private Branch Exchange) software.
- It is designed for efficient communication between Asterisk servers and endpoints.
- IAX can carry both voice and signaling information in a single packet, reducing overhead.
6. MGCP (Media Gateway Control Protocol):
- MGCP is a protocol used for controlling media gateways in a VoIP network.
- It allows centralized control of multiple gateways from a call control server.
- MGCP is often used in conjunction with other protocols like SIP or H.323 for internet telephony.
7. SCCP (Skinny Client Control Protocol):
- SCCP is a proprietary protocol developed by Cisco for communication between Cisco IP phones and Cisco CallManager.
- It is used for call control and signaling in Cisco VoIP networks.
8. ENUM (Telephone Number Mapping):
- ENUM is a protocol that maps telephone numbers to internet resources.
- It allows the use of traditional phone numbers for communication over IP networks.
In summary, the commonly used protocols for internet telephony are VoIP, SIP, H.323, RTP, IAX, MGCP, SCCP, and ENUM. These protocols enable voice communication over IP networks and are essential for the functioning of internet telephony services.