Computer Networking
When one or more computer or networking devices are connected to each other is called Computer Networking. There are three types of Networking
1)LAN(Local Area Network)
2)MAN(Metropolitan Area Network)
3)WAN(Wide Area Network)
LAN(Local Area Network)
1. Local area network is a group of computers connected with each other in a small places such as school, hospital, apartment etc.
2. LANs are not limited to wire connection, there is a new evolution to the LANs that allows local area network to work on a wireless connection.
3. LAN is secure because there is no outside connection with the local area network thus the data which is shared is safe on the local area network and can’t be accessed outside.
4. LAN due to their small size are considerably faster, their speed can range anywhere from 100 to 100Mbps.
Advantages of LAN or Local Area Network
➨ Resource Sharing:
Computer hardware resources like printers, modems, DVD-Rom drives and hard disks can be shared with the help of local area networks. This will reduce cost of hardware purchases. For example, a business organization using a Local Area Network for an office can use a single network printer for the employees of this office.
➨ Software Applications Sharing:
It is cheaper to use same software over network instead of purchasing separate licensed software for each client in a network. It will cost more to purchase a separate licensed software for each computer in a network.
➨Easy and Cheap Communication:
Data and messages can easily be transferred over networked computers. It saves a lot of time and money.
➨ Centralized Data:
The data of all network users can be saved on hard disk of the server computer. This will help users to use any workstation in a network to access their data. Because data is not stored on workstations locally. But it is stored on a server computer. User will access their own data by logging into their accounts from any client computer in the network.
➨ Data Security:
Since, data is stored on server computer centrally, it will be easy to manage data at only one place and the data will be more secure too, because of more security for the server computer.
➨Internet Sharing:
Local Area Network provides the facility to share a single internet connection among all the LAN users. In Net Cafes, single internet connection sharing system keeps the internet expenses cheaper. Because only one high speed internet connection is purchased by a net cafe from any ISP - Internet Service Provider company.
This single high speed internet connection is managed on the server computer of the Net Cafe and available for all network clients with the help of Internet Connection Sharing facilities of the operating system.
Disadvantages of LAN or Local Area Network
➨ High Setup Cost:
Although the LAN will save cost over time due to shared computer resources but the initial setup costs of installing Local Area Networks is high. This is because any organization that will setup a network, will have to purchase necessary hardware equipment for networking.
It may require a sophisticated server computer - a Mini Computer, Network LAN cards, Network Routers, HUBS / Switches, Networking Cables (for wired networks only) and connectors etc. Additionally a Network technician will be required for setting up a new network in an organization.
If an organization has a large network, it must hire a network administrator for smooth running of network and solving any problems.
➨ Privacy Violations:
The LAN administrator has the rights to check personal data files of each and every LAN user. Moreover he can check the internet history and computer use history of the LAN users.
➨ Data Security Threat:
Unauthorized users can access important data of an organization if centralized data repository is not secured properly by the LAN administrator. LAN Administer is responsible for the security of the whole data resource in an organization.
LAN administrator will implement a fully functional security policy for database safety.
➨ LAN Maintenance Job:
Local Area Network requires a LAN Administrator. Because, there are problems of software installations or hardware failures or cable disturbances in Local Area Network. A LAN Administrator is needed at this full time job.
➨ Covers Limited Area:
Local Area Network covers a small area like one office, one building or a group of nearby buildings.
MAN(Metropolitan Area Network)
MAN network covers larger area by connections LANs to a larger network of computers. In Metropolitan area network various Local area networks are connected with each other through telephone lines. The size of the Metropolitan area network is larger than LANs and smaller than WANs(wide area networks), a MANs covers the larger area of a city or town.
Advantages of a metropolitan area network (MAN)
Below are some of the benefits of MAN:-
High Security:-
MAN has a high-security level than WAN.
Less expensive:-
It is less expensive to attach MAN with WAN. MAN gives the good efficiency of data. In MAN data is easily managed in a centralized way.
➨Sending local emails:-
On MAN you can send local emails fast and free.
➨High speed than WAN:-
MAN uses fiber optics so the speed of data can easily reach upon 1000 Mbps. Files and databases can be transferred fast.
➨Conversion from LAN to MAN is easy:-
MAN is a faster way to connect two fast LANs together. This is due to the fast configuration of links.
➨Sharing of the internet:- In some installation of MANs, users can share their internet connection. So multiple users can get the same high-speed internet.
Disadvantages of metropolitan area network (MAN)
Difficult to manage:
If MAN becomes bigger then it becomes difficult to manage it. This is due to a security problem and other extra configuration.
➨Internet speed difference:
MAN cannot work on traditional phone copper wires. If MAN is installed on copper wires then there will be very low speed. So it required the high cost to set up fiber optics for the first time.
➨Hackers attack:
In MAN there are high chances of attacking hackers on the network compared to LAN. So data may be leaked. Data can be secured but it needs high trained staff and security tools.
➨Technical people required to set up:
To setup MAN it requires technical people that can correctly setup MAN. The technical people are network administrators and troubleshooters.
➨More wires required:
In MAN additional cables are required to connect two LAN which is another problem.
Examples of metropolitan area network (MAN)
Some of the examples of MAN are:-
Digital cable television
Used in government agencies
University campuses
Cable broadband
Used to connect several branches of the local school
In hospital (for communication between doctors, research offices, labs)
A network of fire stations
In airports
Networking between community colleges within the country
Used in public libraries
WAN(Wide Area Network)
Wide area network provides long distance transmission of data. The size of the WAN is larger than LAN and MAN. A WAN can cover country, continent or even a whole world. Internet connection is an example of WAN. Other examples of WAN are mobile broadband connections such as 3G, 4G etc.Benefits or advantages of WAN
Following are the benefits or advantages of WAN:
➨Like LAN, it allows sharing of resources and application softwares among distributed workstations or users.
➨WAN covers larger geographical area. Hence business offices situated at longer distances can easily communicate.
➨The software files are shared among all the users. Hence all will have access to latest files. This avoids use of previous versions by them.
➨Organizations can form their global integrated network through WAN. Moreover it supports global markets and global businesses.
➨The emergence of IoT (Internet of Things) and advanced wireless technologies such as LAN or LAN-Advanced have made it easy for the growth of WAN based devices. Messages can be sent very quickly across the globe with the help of applications such as whatsApp, facebook messenger etc.
Drawbacks or disadvantages of WAN
Following are the disadvantages of WAN:
➨It is difficult to maintain the network. It requires skilled technicians and network administrators.
➨Initial investment costs are higher.
➨There are more errors and issues due to wide coverage and use of different technologies. Often it requires more time to resolve issues due to involvement of multiple wired and wireless technologies.
➨Security is big concern and requires use of firewall and security softwares/protocols at multiple points across the entire system. This will avoid chances of hacking by intruders.
➨It has lower security compare to LAN and MAN due to wider coverage and use of more technologies.
