Note: Missing questions can be find at past paper solution of respective subject
Model Set 1
Group A
1. Write any two examples of WAN.
à Two examples of WAN are:
· Internet
· Company network with several branch offices in separate countries.
2. Which topology do you prefer for small sized networks?
à I prefer bus topology for small sized networks.
3. What is IP address?
à IP address is a logical numeric address that is assigned to every single node on TCP/IP based network.
4. What is gateway?
à A gateway is a network node used in telecommunications that connects two networks with different transmission protocols together.
5. Define bits and packets.
à The protocol data unit of physical layer is called bits whereas the protocol data unit of network layer is called packets.
Group B
6. Write the home application of computer network.
à The home application of computer network are:
· Access to the remote information
· Person to person communication
· Interactive entertainment
· Ecommerce
7. Draw a figure of star topology.
Ã
8. Classify IPV4 address.
à IPv4 address is classified into five classes. They are:
· Class A
· Class B
· Class C
· Class D
· Class E
9. Why bridge is used?
à A network bridge is used to create a single, aggregate network from multiple communication networks or network segments.
10. Draw the figure of twisted pair cable.
à A twisted pair consists of two conductors (normally copper), each with its own plastic insulation, twisted together. One of the wires is used to carry signals to the receiver, and the other is used only as a ground reference. Twisted pair cables are the most effective. It has lower bandwidth and high attenuation. The most common application of the twisted pair is in the telephone system and in LAN. Twisted pair can only run few meters without amplification, but for longer distance, repeaters are needed. There are two types of twisted pair cables:
· Shielded twisted pair cable: STP cable has a metal foil or braided mesh covering that encases the pairs of insulated conductors. Although metal casing improves the quality of cable by preventing the penetration of noise or crosstalk, it is bulkier and more expensive.
· Unshielded Twisted pair cable: The most common twisted-pair cable used in communications is referred to as unshielded twisted-pair (UTP). It doesn’t have any metal foil or braided mesh covering. It is cheaper.
11. Explain in short about Web security.
à It basically means protecting a website or web
application by detecting, preventing and responding to cyber threats.
Today’s most of the work is web based. Either that is communication or transportation, medicine, shopping, etc we need to access different websites in order to complete them. Web sites are unfortunately prone to security risks. With great regularity, we hear about websites becoming unavailable due to denial of service attacks, or displaying modified (and often damaging) information on their homepages. The purpose of website security is to prevent these (or any) sorts of attacks.
Group C
12. Explain wireless network in brief.
à Wireless network is any type of computer network that uses wireless data connections for connecting network nodes. Wireless networks are the alternative of traditional wired networks that relies on cables to connect the device with each other. They generally use radio waves for communication between the network nodes.
Type of wireless networks:
• Wireless Local area Network (WLAN): A wireless LAN (WLAN) is a wireless computer network that links two or more devices using wireless communication to form a local area network (LAN) within a limited area such as a home, school, computer laboratory, campus, or office building. This gives users the ability to move around within the area and remain connected to the network.
• Wireless Metropolitan area Network (WMAN): WMAN is a wireless metropolitan area network that can cover a whole city. It is larger than WLAN (wireless local area network) and smaller than WWAN (wireless wide area network). WMAN is managed by any private organization or government agencies.
• Wireless Wide area Network (WWAN): this network connects several wireless LANs and wireless MANs within cities or countries.
• Wireless Personal Area Network (WPAN): this interconnects devices in a short distance, generally within a person's reach. Their range is very limited.
13. Write the disadvantages of bus topology.
à The disadvantages are:
· It is difficult to detect and troubleshoot the errors.
· There is maximum chance of data collision.
· Network slows down if additional computers are added.
· Whole network stops functioning if the backbone cable is damaged.
14. What are the different transmission media? Explain optical fiber cable with its advantages and disadvantages.
à The different types of transmission media are:
· Wired Media
o Optical fiber
o Twisted pair Cable
o Coaxial Cable
· Wireless Media
o Satellite
o Microwave
o Radio transmission
already explained above.
15. Describe VPN in detail.
à A virtual private network is technology that creates a safe and encrypted connection over a less secure network, such as the internet. It allows remote users to securely access applications and other resources. In VPN, data travels through secure tunnel.
Advantages:
· Enhanced security: when the network is connected to through VPN the data is kept secured and encrypted which provides security.
· Unlock websites and bypass filters: VPNs are great for accessing blocked websites or for bypassing internet filters.
· Better performance: The bandwidth and efficiency of the network can be generally increased once VPN is implemented.
· Reduce Cost: The maintenance cost is very low when VPN is implemented.
Model Set 2
Group A
1. What is Bluetooth?
à Bluetooth is a wireless technology standard for exchanging data over the short distance (using short wavelength radio transmission) from fixed and mobile devices, creating a personal area network with the high level of security.
2. Write IPV4 frame format.
à The frame format of IPV4 is X.X.X.X where X is called an octet and must be a decimal value between 0 and 255.
3. Why is switch used?
à A Switch is used to transfer the data only to the device that has been addressed in a network.
4. Which device works on network layer?
à Router works on network layer
5. Define message.
à The protocol data unit of application layer is called message.
6. Define cipher text
à Cipher text is an encrypted message or unreadable message after encryption.
Group B
7. Why gateway is used?
à Gateway is used to convert the information, data or other communication from one protocol format to another allowing multiple networks with different transmission protocols to connect with each other.
Group C
8. Write the advantages and disadvantages of star topology.
à Advantages:
· It is easy to setup and configure
· It is easy to detect error in this topology.
· Failure of single node doesn’t affect whole network.
· Hub can be upgraded easily
· Easy to add or remove nods
· Centralized management helps in monitoring the network.
Disadvantages:
· It requires more cables in comparison to bus topology.
· Failure of central switch/hub breaks down the whole network.
· Capacity of central device determine the numbers of nodes and performance of star topology.
· It is expensive than bus topology due to cost of central device and more cables.
· Data traffic, data collision rate and data error rate will be high.
9. Explain the satellite with advantages and disadvantages.
à A satellite is a physical object that revolves around the earth at a known height. Satellite communication is more reliable nowadays as it offers more flexibility than cable and optic fiber systems. We can communicate with any point on the globe by using satellite communication. It uses a satellite as a repeater. Satellite communication systems have receivers and transmitters located in ground stations. The satellite accepts the signal that is transmitted from the earth station, and it amplifies the signal. The amplified signal is retransmitted to another earth station. To make communication possible in the even long distance, multiple satellites are used.
Applications:
· In radio broadcasting
· In TV broadcasting
· For voice transmission
· In military applications.
Advantages:
· It is cover a more area than the terrestrial microwave.
· Over long distance, it is cheaper.
· It used in mobile and wireless communication application.
Disadvantages:
· Satellite designing and developing requires more time and higher cost.
· It needs to be monitored and controlled on regular periods.
· The life of the satellite is about 12- 15 years. Due to this reason, another launch of the satellite has to be planned before it becomes non-functional.
· Satellites are not easy to repair and maintain.
Model Set 3
Group A
1. What is Wi-Fi?
à Wi-Fi is the wireless technology used to connect the computers, tablets, smartphones and other devices to the internet.
2. Why WAN can connect more devices?
à WAN can connect more devices because it is spread to a wide geographical area such as multiple cities, districts, or nations.
3. Write any two application of computer network.
à The application of computer network are:
· To share information and hardware resources.
· To facilitate the communication via email, video conferencing, instant messaging etc.
4. What is subnet mask?
à A subnet mask is a 32-bit number that distinguishes the network address and the host address within an IP address.
5. What is communication media?
à It is the channel through which data is transferred from one device to another in a network.
6. Write any two advantages of using switch.
à Two advantages of using switch are:
· They increase the available bandwidth of the network.
· They help in reducing workload on individual host PCs.
· They increase the performance of the network.
· Networks which use switches will have less frame collisions. This is due to the fact that switches create collision domains for each connection.
· Switches can be connected directly to workstations.
7. Which device works on physical layer?
à Devices like HUB, repeater, Modem, Cables etc. works on Physical Layer.
Group B
8. Why Hub is used?
à Hub is used to connect multiple devices in a network generally in star topology.
Group C
9. Describe the application of computer network.
à The applications of computer network are described below:
· Information and Resource Sharing: Programs and software in any computer can be accessed by other computers linked to the network. It also allows sharing of hardware equipment, like printers and scanners among varied users.
· Accessing the remote information: People can have access to the information on any subject either news, business, politics and many others by surfing the internet. Educational and informative websites are available to download books, tutorials etc. to improve their knowledge and learn new things.
· E-Commerce: e: E-commerce or Electronic Commerce is the process of buying or selling goods online. Due to the busy life people don’t get time to go for shopping, moreover that different online shopping sites provide varieties of goods and deliver to our doorsteps. It has make shopping easier. By sitting in the room, using their computer network people can buy their needed goods.
· Communication: People can communicate with friends and family on the internet using different software like Skype etc. One can interact with friends over social media websites like Facebook, Twitter. They can also share photos and videos with friends. Video calls, group chat, group call are based on computer network which are the most modern ways of communicating among people.
10. Write any four disadvantages of Ring topology.
à Disadvantages:
· Failure of one node affects the whole network.
· Troubleshooting is difficult than star topology.
· Data packet needs to pass through all nodes between source and destination, so it is time consuming.
· In order for all the computer to communicate with each other, all computer must be turned on.
11. Explain client server architecture with necessary figures.
à Client Server Architecture is a network architecture in which the server hosts, delivers and manages most of the resources and services to be consumed by the client. This type of architecture has one or more client computers connected to a central server over a network or internet connection. Clients are often situated at workstations or on personal computers, while servers are located elsewhere on the network, usually on more powerful machines.
When clients send a request to the server over the network connection, server processed and deliver the services to the client.
Type of Client-Server Architecture:
o 1-tier client-Server architecture: In 1-tier architecture the user interface, business logic and data logic are present in same system. It is cheapest. It is difficult to handle because of data inconsistency that allows repetition of work.
o 2-tier client-server architecture: In 2-tier architecture the user interface is stored at client machine and databases are stored on server. Database logic and business logic are stored at either client or server but it must be unchanged. In this architecture client talks directly to sever so that it is useful. If business logic and data logic are stored at client side, it is called fat client thin server architecture. If business logic and data logic are stored on server, it is called thin client fat server architecture.
o 3-tier client-server architecture: In 3-tier architecture environment an additional middle-ware is used. So that client request goes through that middle layer and the response of server is firstly accepted by middleware then to client. The middle-ware stores all the business logic and data access logic. The middle-ware can be file server, message server etc. It improve flexibility and gives best performance.
Advantages:
· Centralized administration is possible through the network.
· High security can be provided by using the appropriate server.
· It is appropriate for a large organization having a large number of computers.
· Data recovery and backup process is easier.
Disadvantages:
· It is expensive due to the use of dedicated servers.
· It is complex to establish and manage.
· Skilled administrators are required to implement and manage the network.
· If the server fails, it will affect the network
12. Explain microwave with advantages and disadvantages.
à Microwave system uses very high-frequency radio signal to transmit data through the air. Microwaves travels in straight lines. So, both sender and receiver must be aligned to be strictly in line-of-sight. Microwaves have higher frequencies and do not penetrate wall like obstacles. With microwave very long distance transmission is not possible. In order to overcome the problem of the line of sight and shorter distance, repeaters are used at intervals of 25 to 30 km apart. When one repeating tower receives signal, it amplifies the signal and sends it to next tower. It depends highly upon the weather conditions.
Applications:
· Long distance telephone communication
· Cellular Phones
· Television networks
· Wireless LANs
Advantages:
· It has a larger bandwidth and hence a large amount of information can be transmitted using it.
· Microwave communication is used since earlier days as one of the Line of Sight Communication in hilly remote areas where other means of wired communication is not possible to be installed. Microwave and satellite communications are prefect choice in such places.
Disadvantages:
· There shouldn’t be obstacle in the transmission path.
· The cost of implementing the communication infrastructure is too much high.
· Microwave is susceptible to rain, snow, and electromagnetic interference.
· The main disadvantages are microwave communication is limited to line of sight mode only, other modes of communication are not possible.
13. Explain digital signature in details.
à Digital signature is a mathematical technique used to validate (confirm) the authenticity and integrity of message, digital document. It is used for software distribution, financial transactions. It can play a ro.le as played by handwritten signature for printed documents.
Digital signatures work by proving that a digital message or document was not modified—intentionally or unintentionally—from the time it was signed. Digital signatures do this by generating a unique hash of the message or document and encrypting it using the sender’s private key. The hash generated is unique to the message or document, and changing any part of it will completely change the hash.
Once completed, the message or digital document is digitally signed and sent to the recipient. The recipient then generates their own hash of the message or digital document and decrypts the sender’s hash (included in the original message) using the sender’s public key. The recipient compares the hash they generate against the sender’s decrypted hash; if they match, the message or digital document has not been modified and the sender is authenticated.
Model Set 4
Group A
1. What is computer network?
à Computer network is the group of two or more computing device linked together for the purpose of communicating, sharing information and other hardware resources.
2. Which device is used as central controller in star topology?
à Hub is used as central controller in star topology.
3. Define frame and packet.
à The PDU of data-link layer is frame and the PDU of network layer is packet.
Group B
4. Difference between IPv4 and IPv6 format.
Ã
IPv4 | IPv6 |
It has 32 bit address length | It has 128 bit address length. |
Address representation is in decimal | Address representation is in hexadecimal |
It doesn’t have security features | It has security features |
Data prioritization is not up to date | Data prioritization is up to date |
It doesn’t have auto configuration. | It has auto configuration. |
5. Why gateway is the combination of router and bridge?*
à Brouter is the combination of router and bridge because it can forward data between networks (serving as a bridge), but can also route data to individual systems within a network (serving as a router).
Group C
6. Explain home networks in brief.
A home network or home area network is a type of computer network that facilitates communication among devices within the close vicinity of a home. A home network allows the computer owner to interconnect multiple computers so that each they can share files, programs, printers, other peripheral devices, and internet access among them. It reduces the need for redundant equipment and makes everything easier to use.
7. Which network architecture is cost effective? Why? Explain in brief.
à Peer to peer network architecture is cost effective. In peer to peer architecture, there is not any server and each users can manage their own system, so there is not requirement of dedicated system administrator. Thus the cost of the dedicated server and the dedicated system administrator is reduced in the peer to peer architecture.
0 Comments