LAN & WAN Networking
Every LAN may or may not be with WAN but every WAN will be with LAN.
A computer network is a group of computers linked to each other that enables the computer to communicate with another computer and share their resources,data,and applications.LAN and WAN are some of the types of computer network.
Local Area Network (LAN)
It is a computer network that spans a relatively limited area.Most often,a LAN is confined to a single room, school,residance,university campus or office building. Ethernet,token ring,Fiber distributed data interchange (FDDI),TCP/IP and asynchronous transfer mode(ATM) are the most common protocol that is used in this network.
PC’s,laptops and workstations in an office are generally inter-connected with each other by using LAN networks through which we can share data files,software,e-mail and access hardware such as printers,FAX etc.All the resources or host are connected via a single cable in LAN.
Wide Area Network (WAN)
A wide area network is a large network of information that is not tied to a single location.It is a form of telecommunication networks that can connect devices from multiple locations and across the globe. Internet,mobile broadband connections such as 3G,4G etc. are the WAN networks.
Mobile operators and service providers like NSN or Ericsson use WAN network to provide mobile services in a particular circle.Different circles of a country are also connected with each other through WAN networks.The connections are made through routers and switches using higher bandwidth STM links.
Correlation between LAN and WAN :
LANs would allow organizations to work within their building,but growth to outside areas — either different cities or even different countries — would not be possible, although organization grow and become international this is possible only because of WAN. WAN allow them to communicate between branches,share information and stay connected all over the glob.WAN must be connected to LAN to transfer data from one source to all over the wide portion.While all LANs are not connected with WANs some of them are accessible within a one building.
Let’s understand it with the help of an example —
Consider the case of an MNC where the head office is situated in Delhi and the regional offices are situated in Bangalore and Mumbai.Here, all are connected through WAN network.If HOD’s of corporate office want to share some data with their regional office mates then they can share data(image,video or any data of big size) by saving it on the centralized node which can be accessible by everyone in the organization and is on one single network only.The centralized server is maintained by an administrator who has rights to grant access to the users connected to main server.The administrator will allow sharing only that information which is of the scope of the client nodes.The rights are reserved for confidential data and only a few higher level authorities of the company will have the rights to access it.The software tester can also work in this scenario and can share their tools with their colleagues situated hundreds of km away in just a few minutes by using WAN network.For all this WAN network must be connected with the LAN.
Now suppose in a university,all the hosts are connected through LAN,then one of the PC can be converted into server and all the other PC’s will be clients which can have access to the data stored on the client computers.By having this kind of a facility the Dean and the professors of the university can easily share data or resourses with each other as they are on the same network.But this data may or maynot be accessible outside the university depending on whether it is connected with WAN network or not.This means that LAN may or may not be connected with WAN.
