CUET Information practice (IP) Chapter 1 Computer Networking

(a)

Exp: A router is a network device that connects multiple networks irrespective of their protocol. In general, a router only forwards a packet to a single outgoing link.

(c)

Exp: Computer network connects two or more autonomous computers. Computer network is a set of two or more interconnected computers and a set of hardware devices.

(c)

Exp: In a non-dedicated server, a computer works as a workstation as well as a server. In dedicated server, a computer is dedicated for a server’s job and its only job is to help workstations access data, software and hardware resources.

(b)

Exp: A Point-to-Point link is a dedicated link that connects exactly two communication facilities. E.g., two nodes of a network.

(d)

Exp: Resource sharing ismaking data, programs and peripherals available on the network. It is one of the goals of networking.

(b)

Exp: A node is any device connected to a computer network. Nodes can be computers, personal digital assistants (PDAs), cell phones, or various other network appliances. On an IP network, a node is any device with an IP address.

(a)

Exp: A network protocol defines rules and conventions for communication between network devices. Protocols for computer networking all generally use packet switching techniques to send and receive messages in the form of packets.

(c)

Exp: An Internet Protocol (IP) address is a unique series of numbers that is assigned to devices participating in a computer network that uses Internet Protocol for communication between its nodes.

(d)

Exp: A domain name is used to translate a host name into an IP address. It comprises a hierarchy so that the names are unique.

(c)

Exp: A ring topology is a physical, closed loop consisting of point-to-point links. Here, the data travels in circular fashion from one computer to another on the network.

(b)

Exp: The bus topology is also known as linear topology. It uses a trunk or backbone to which all the computers on the network connect.

(d)

Exp: The tree topology has integrated multiple star topologies onto a bus. In this topology, the packets are automatically removed from the medium and are absorbed by terminators.

(b)

Exp: PAN is a computer network organised around an individual person. It can be wired or wireless. It generally covers a range of 10 metres.

(c)

Exp: Online messaging, also known as instant messaging is similar to e-mail. However, the only difference is that the message is sent immediately.

(a)

Exp: Crosstalk is an interference caused by adjacent wires. It is particularly significant problem because large numbers of cables often are located close together with minimal attention to exact placement.

(c)

Exp: Guided media is also known as wired technology. Twisted pair cable consists of a number of pairs bundled together. It may be used to transmit both analog and digital transmission.

(b)

Exp: WAN is the largest network and can interconnect networks throughout the world. WANs are networks that are found where computers in different areas or countries need to communicate.

(b)

Exp: MAN(Metropolitan Area Network) is far larger than a LAN and smaller than a WAN. MAN provides interconnectivity for LANs in a metropolitan region and connects them to a wider area networks like the Internet.

(c)

Exp: Radio-wave transmission makes use of radio frequencies. Radios use continuous sine wave to transmit information (e.g. audio, video, data).

(b)

Exp: All radios use continuous sine waves to transmit information. A radio set up has a transmitter and a receiver. Transmitter takes the message, encodes it onto a sine wave and transmits it with radio waves.

(a)

Exp: A hub is used to connect several computers together. Hubs can be either active or passive. Active hubs electrically amplify the signal as it moves from one connected device to another while passive hubs allow the signal to pass from one computer to another without any change.

(d)

Exp: A switch is a device used to segment networks into different sub networks called subnets. A switch is responsible for transforming data in a specific way.

(c)

Exp: A repeater is a device that amplifies and restores the power of a signal being transmitted on the network. It is used in long network lines. Repeaters can be installed along the way to ensure that data packets reach their destination.

(b)

Exp: A concentrator is a device that provides central connection point for cables from workstations, servers, and peripherals. In a star topology, twisted-pair wire is run from each workstation to a central concentrator. Hubs are multislot concentrators into which a number of multi-port cards can be plugged to provide additional access as the network grows in size.

(b)

Exp: Sending of data from one device to another is called transmission of data. Transmission of data through medium is called Transmission Media. Telephone lines are an example of transmission medium.

(c)

Exp: A bridge is a functional unit that interconnects two local networks that uses same logical link control protocol but may use different medium access control protocols.

(d)

Exp: A gateway is a device which allows different electronic networks to talk to Internet that uses TCP/IP. It establishes connection between a local network and external networks with completely different structures.

(b)

Exp: The MAC address is a unique value associated with a network adapter. MAC addresses are also known as hardware addresses or physical addresses. They uniquely identify an adapter on a LAN.

(c)

Exp: A router is used to load balance between various paths that exist on networks. Routers can attach physically different networks.

(a)

Exp: A computer network connects two or more autonomous computers. The computers can be geographically located anywhere.

(d)

Exp: A local area network (LAN) is a network that connects a relatively small number of machines in a relatively close geographical area.

(a)

Exp: Bluetooth is a low-cost, low power, short range wireless communication technology used in networking, mobile phones and other portable devices. It enables devices to communicate with each other as soon as they come in range.

(c)

Exp: WAN is a network that connects local-area networks over a potentially large geographic distance. These networks are found where computers in different areas or countries need to communicate.

(b)

Exp: When there is a direct link between each host in a network, then the network is said to be fully connected.

(c)

Exp: PAN is a computer network organised around an individual person. This network is used to transfer files including email, music, digital photos etc.

(c)

Exp: Repeater is a device that amplifies and restores the power of a signal being transmitted on the network. It is installed to ensure that data packets reach their destination.

(a)

Exp: FTP represents network functionality that enables users to upload web page files (simple text files, images, multi-media files etc.) from their personal computers to the server where their websites are located and vice versa – to download files from a particular server to their own machines.

(a)

Exp: In star topology, all computers/devices connect to a central device called hub or switch. One of the advantages of star topology is the centralized control/problem diagnosis. Since the central node is connected directly to every other node in the network, the faults are easily detected and isolated.

(a)

Exp: The linear topology, also known as bus topology, uses a backbone to which all of the computers on the network connect. The advantages of this topology are its short cable length and simple wiring layout, is cheap and easy to implement. Also, it does not use any specialised network equipment.

(c)

Exp: Network Interface Card is a device that serves as a common interface for various other devices within a LAN. It is an interface to allow networked computers to connect to an outside network.

(c)

Exp: LANs are networks that are found where computers within a building need to communicate. MAN is a large computer network that usually spans a city or a large campus. WANs are networks that are found where computers in different areas or countries need to communicate.

(d)

Exp: MAN is a large computer network that usually spans a city or a large campus. MAN provides interconnectivity for LANs in a metropolitan region and connects them to a wider area networks like the Internet.

(c)

Exp: LANs are networks that are found where computers within a building need to communicate. A LAN connects computers, printers and modems (whatever is on the network) together within a small geographic area.

(a)

Exp: A node is an electronic device on the network such as a PC, printer or fax machine.

(c)

Exp: Ethernet is the most popular and least expensive way information can travel through a network.

(d)

Exp: The NIU (network interface unit) is also called NIC(network interface card). The NIC manufacturer assigns a unique physical address to each NIC card. NIC allows a flow of information between a network and a PC.

(a)

Exp: Remote access gives mobile users access to company network as well as people networked employees who work from home. Network access is generally limited to authorised company employees.

(b)

Exp: You should invest in equipments that suit your immediate needs. Also, that allows you to build on the initial investment as your company grows.

(c)

Exp: In a star network, all computers/devices connect to a central device called hub or switch. Each device requires a single cable point-to-point connection between the device and hub.

(a)

Exp: Bus network topology is a network architecture in which a set of clients are connected via a shared communications line called a bus. Bus is considered a multipoint system as all devices tap into same backbone cable.

(d)

Exp: Internetis a worldwide system of computer networks: a network of networks in which users at any one of the computers can, if they have permission, get information from any other computer (and sometimes talk directly to users at other computers).

(c)

Exp: Internetis a worldwide system of computer networks: a network of networks in which users at any one computer can, if they have permission, get information from any other computer (and sometimes talk directly to users at other computers).

(b)

Exp: Each network device (a computer or any other device) on a TCP/IP network needs to have a unique address on the network. This unique address on a TCP/IP network is the IP address. IP addresses are needed so that different networks can communicate with each other.

(c)

Exp: World Wide Web, abbreviated as WWW and commonly known as Web, is a system of interlinked hypertext documents contained on the Internet.

(a)

Exp: The NIC manufacturer assigns an exclusive physical address to each NIC card. This physical address is known as Media Access Control.

(c)

Exp: Network Interface Unit (NIU) (sometimes called network interface device) is a device that serves as a common interface for various other devices within a local area network (LAN) or as an interface to allow networked computers to connect to an outside network. NIU is also called Terminal Access Point (TAP).

(d)

Exp:Mesh Network is a network where all the nodes are connected to each other and it is a complete network. In a Mesh Network, every node is connected to other nodes on the network through hops. Some are connected through single hops and some may be connected with more than one hops.

(b)

Exp: In a graph topology, it is not necessary that all nodes are connected.

(b)

Exp: A collection of computing devices connected in order to communicate and share resources is known as computer network. The types of network are local area network, metropolitan area network, wide area network (e.g. Internet) and personal area network.

(d)

Exp: In a bus topology, all devices attach to same transmission medium. Bus is considered a multipoint system as all devices tap into same backbone cable. It has terminators at either ends that absorb the signal, removing it from the bus.

(b)

Exp: The data is transmitted in small blocks known as packets. Each packet has some data bits and a header containing its destination address.

(a)

Exp: The intentional interception of someone else’s data such as email, login id, password etc. is known as eavesdropping.

(c)

Exp: The address resolution protocol (ARP) is used by Internet Protocol (IP), specifically IPv4, to map IP network addresses to the hardware addresses used by a data link protocol.

(a)

Exp: Name resolution tries to resolve some of the numerical address values into a human readable format. In other words, the URL is mapped to an IP address.

(b)

Exp: The intrusion problem or access attack is an attack against confidentiality of information. Some common attacks are snooping, eavesdropping and denial of service.

(d)

Exp: File access permissions refer to privileges that allow a user to read, write or execute a file. If a user has Read permission for a file, he/she can view and read the file. If a user has Write permission for a file, he/she can edit and write into the file. If a user has Execute permission for a file, he/she can execute the file.

(b)

Exp: Authorisationis the process of giving someone permission to do or have something. Asking the user a legal login-id performs authentication.

(d)

Exp: Authenticationis also termed as password-protection as the authorised user is asked to provide a valid password and if he/she is able to do this, he/she is considered to be an authentic user.

(c)

Exp: An intrusion detection system (IDS) is a device (or application) that monitors network and/or system activities for malicious activities or policy violations and produces reports to a Management Station.

(b)

Exp: A firewall is a part of a computer system or network that is designed to block unauthorised access while permitting authorised communications.

(d)

Exp: Demodulation is the process of decoding an analog signal into digital data. When data is transferred over phone lines, a modem modulates the data into audible tones "carried" on frequencies between 0 Hz and 4 KHz. Once the data reaches its intended destination, another modem demodulates the signal back into digital data. Cable TV networks also use modulation techniques to transfer data. But instead of audible tones, cable has sophisticated digital modulation schemes to greatly increase the amount of data that can be sent.

(c)

Exp: The act of processing digital data into analog data is known as modulation.

(b)

Exp: The twisted pair cable is a transmission medium consisting of two insulated wires arranged in a regular spiral pattern. Twisted pair cable is a type of cabling that is used for telephone communications.

(c)

Exp: Repeater reads the incoming packet, amplifies it and transmits it to another segment of the network. For example, Ethernet is a nine-port repeater that can connect thin wire from digital to other wire cables.

(a)

Exp: A bridge is a functional unit that interconnects two local area networks (LAN) that use the same logical link control protocol but may use different medium access control protocols.

(d)

Exp: A switch is inexpensive and offers better performance than a hub. The switch filters and forwards data packets across a network.

(b)

Exp: Modulation is the process of sending data on a wave. Three types of modulation techniques are used and they are: Amplitude Modulation (AM), Phase Modulation (PM) and Frequency Modulation (FM).

(d)

Exp: Internal modems are fixed within the computer while external modems are connected externally to a computer as other peripherals are connected.

(b)

Exp: Fibre optics (optical fibres) are long, thin strands of very pure glass about the diameter of a human hair. They are arranged in bundles called optical cables and used to transmit light signals over long distances.

(d)

Exp: Denial-of-service attacks prevent the legitimate users of the system from accessing or using the resources, information or capabilities of the system.

(c)

Exp: The main disadvantage of fibre optics is that the cables are expensive to install.

(a)

Exp: The most economic way to connect it with reasonable high speed would be to use radio transmission, as they are easy to install, can travel long distances and penetrate buildings easily. Therefore, they are widely used for communication, both indoor and outdoor.

(c)

Exp: The area coverage through satellite transmission is quite large. Since the laying and maintenance of long distance cable is difficult and expensive, satellites prove to be the best alternative.

(b)

Exp: A network that connects local-area networks over a potentially large geographic distance is known as Wide Area Network (WAN). WANs are found where computers in different areas or countries need to communicate.

(d)

Exp: A switch/hub enables more than one computer (host) to interconnect on a network. The main function of a hub is to share resources like files, a printer, a scanner or Internet access over a network. The switch filters and forwards data packets across a network.

(c)

Exp: If the central node in a star network fails, the entire network is rendered inoperable. This introduces heavy reliability and redundancy constraints on this node.

(a)

Exp: A bridge is a device which is used to connect two local-area networks or two segments of the same LAN.

(a)

Exp: Repeaters are installed to ensure that data packets reach their destination. They are of two kinds: amplifier amplifies all incoming signals over the network whereas signal repeater collects the inbound packet and then retransmits the packet as if it were starting from the source station.

(c)

Exp: To communicate on an internetwork, MAC address is not enough. IP address of the destination machine is needed.

(b)

Exp: MAC address refers to the physical address assigned by NIC manufacturer.