Computer Networking Notes and Questions to revise in 1 Hour
- What is a network and networking?
A computer network is a collection of interconnected computers and devices so as to exchange information or share resources. The largest network is Internet
The act of connecting computers to enable them to share resources is known as networking.
- What are Advantages and Disadvantages of network?
- Share Resources- Such as printers and scanners
- Share Software- Software can be installed centrally
- Share storage- files can be accessed from any machine on the network
- Improve communications-Internal messages can be sent
- The systems are more sophisticated and complex to run. This can add to costs and you need specialist staff to run the network.
- Software and files are held centrally, it may be impossible to carry out any work if central server fails
- If networks are badly managed, services can become unusable and productivity fails.
- What are the different ways in which network can be classified?
Network can be classified based upon
- Based upon area covered
- Based upon architecture
- Based upon topology
- What are the types of networks based upon area covered?
- Or Give Differences between LAN / MAN / WAN?
- Or What is LAN? MAN? WAN? Give 2 points.
|LAN stands for Local Area Network.||MAN stands for Metropolitan Area Network.||WAN stands for Wide area network.|
|Usually connected to small area, within the same building.||Larger network that usually spans several buildings in the same city or town.||Network that covers large geographical area even across countries.|
|Connected typically with cables, wires or wireless technology.||MAN’s ownership can be private or public.||While WAN also might not be owned by one organization.|
|The transmission speed of LAN is high.||While the transmission speed of MAN is average.||Whereas the transmission speed of WAN is low.|
|Low cost||Moderate cost||Expensive|
|e.g. Small Office, building, schools||e.g. ATM network.||e.g. Internet|
- What is topology? What are different types of network based upon topology?
- Or What is Star? Ring? Bus? Tree Topology? Give 2 points each?
- Or What is the difference between star and ring? Ring and bus? Star and Tree?
Topology refers to arrangement of computers on network. Different topology are as shown.
|Description||A single cable carries the entire data. Every device is connected to the bus.||All computers connected in closed circle.||All computers connected to central server.||Every node is connected to other node.||Combines Bus and Star|
|Disadvantage||Failure in backbone causes disruption to entire network||Failure in any node can disrupt the entire network||If server fails entire network fails.||Installation and maintenance is difficult||Installation and maintenance is difficult|
|Network Performance||Moderate||Small or Moderate||Small||Small||Large|
|Cable Length Requirement||Less||Moderate||More||More||Moderate|
- What is a transmission medium?
Transmission medium refers to device or technology by which data is transferred from one computer to another.
- Mention different types of cables used in wired networks
- Twisted Pair Cable– It is a pair of insulated wires that are twisted together to improve electromagnetic capability and to reduce noise from outside source.
- Coaxial Cable(Coax)- This type of cable consists of a solid wire core surrounded by one or more foil or wire shields, each separated by some kind of plastic insulator
- Fiber Optic Cable-It consists of a bundle of glass threads, each of which is capable of transmitting messages modulated onto light waves
- Which are the most commonly used transmission media in wireless networks?
- Microwave-Microwave are high frequency waves that can be used to transmit data wirelessly over long distances. The Microwave transmission consists of a transmitter, receiver and the atmosphere
- Radio waves– it can be classified by frequency and wavelength .Radio waves are used to transmit television and radio programmes
- Satellite Microwave-Satellite communication is a special case of microwave relay system. Satellite communication use the synchronous satellite to relay the radio signal transmitted from ground station
- What transmission medium is used for short or long distance?
- Short: Twisted pair, Coaxial
- Long: Fibre Optics, Radio Waves, Micro Waves, Satellites.
- Compare fiber optic cable with Ethernet cables? Also tell when wireless cables are more advantageous over wired cables.
Ethernet uses copper cables to deliver data using electrical impulse, and it has a reputation of being a lot slower than fiber optic cables. … Now, however, “fast Ethernet” offers rates of up to 100Mbps, while Gigabit Ethernet can deliver speeds of a hefty 1000Mbps.
- How many wires are there in twisted pair cable(Ethernet)? What is the name of connector which is used to connect it with Ethernet port?
2 pairs of wires in twisted pair cable and RJ45 is used to connect it with Ethernet port.
- Assume that 50 employees are working in an organization. Each employee has been allotted a separate workstation to work. In this way, all computers are connected through the server and all these workstations are distributed over two floors. In each floor, all the computers are connected to a switch. Identify the type of network?
Ans. LAN(Local Area Network)
- What is Hub and mention different types of Hub
A hub is a hardware device used to connect several computers together. A hub contains multiple independent nut connected modules of network and inter-networked equipment.
A concentrator is a device that provides a central connection point for cables from workstations, servers and peripherals. Hubs are multi-slot
concentrators into which of multi-port cards can be plugged to provide additional access as the network grows in size.
Hubs can be either passive or active.
- Active Hubs-electrically amplify the signal as it moves from one connected device to another.
- Active concentrators are used like repeaters to extend the length of a network
- Passive hubs allow the signal to pass from one computer to another without any change
- What is the difference between Hub, Switch and Router?
|1.||Hub is the least expensive, least intelligent and least complicated of the three||Switches work similarly like Hubs but in a more efficient manner||The router is smartest and most complicated out of these three. It comes in all shapes and sizes|
|2.||It broadcasts all data to every port which may cause serious security and reliability concern||It creates connections dynamically and provides information only to the requesting port||Routers are similar like little computers dedicated for routing network traffic|
|3.||In a network, Hub is a common connection point for devices connected to the network. Hub contains multiple ports and is used to connect segments of Lan||Switch is a device in a network which forwards packets in a network||Routers are located at gateway and forwards data packets|
- What is a Gateway
A Gateway is a network device that connects dissimilar networks. It establishes an intelligent connection between a local network and external networks with completely different structures.
In homes the gateway is the ISP that connects the user to the internet. In enterprises, the gateway node often acts as a proxy server that means it acts as a server.
- What are Routers and purpose of using it?
A Device that works like a bridge but can handle different protocols, is known as Router.
A router can locate the destination required by sending the traffic to another router, if the destination is unknown to itself. The router is responsible for forwarding data from one network to a different network.
E.g. A router can link Ethernet to a mainframe
Short Questions with Answers on Computer Networking
- Give Full forms of the following?
- NIC– Network Interface Unit
- LAN-Local Area Network
- WAN-Wide Area Network
- MAN– Metropolitan Area Network
- NIC– Network Interface Card
- WAP– Wireless Access Point
- P2P Networks– Peer- to- Peer Networks
- Fill in the Blanks
- A computer becomes a _______________ of a network as soon as it is attached to a network.
- _________ Networks are popular as home networks and for use in small companies.
Ans. Peer- to –Peer
- A twisted pair cable is a pair of_________ wires that are twisted together to improve.
- ___________ waves are high frequency waves that can be used to transmit data wirelessly. over long distances
- __________Waves are used to transmit television and radio programmes.
- _________ communication is a special case of microwave relay system.
- A _______ is networking device having multiple ports that are used for connecting multiple computers or segments of a LAN together.
- A __________ is a device that is used to segment networks into different sub networks called subnets or Lan segments
- _______is a device that forwards data packets along networks.
- A ______________is a device that lets you link two networks together.
- A __________ works like a bridge but can handle different protocols.
- _______________establishes an intelligent connection between a local network and external networks with complete different structures
- __________ Cable consist of bundle of glass threads each of which is capable of sending messages on light waves.
Ans. Fiber Optics
- _____a device that amplifies a signal being transmitted on the network.
- ______is a hardware device that acts as a “gate” between two networks. It may be a firewall, server, or other device that enables traffic to flow in and out of the network.
- A _________ is a topology for a Local Area Network (LAN) in which all the nodes are connected to a single cable. The cable to which the nodes connect is called a “backbone”.
- _____is a network device that connect dissimilar network.
- The fastest guide media is ______.
Ans. Twisted Pair
- Combination of two or more networks are called_____.
- _____is the largest network.