Every WAN is with LAN …But Every LAN may or may not be with WAN

Computer Networking has brought world closer, because of which we are able to communicate easily with each other from large distances. Faster and secured data transfer is possible due to networking. We all have experienced it in daily life but let us get some knowledge about Networking, so what is a computer network?..connections of computer like devices right!!
To be more technical ,network consists of two or more computers, devices that are linked in order to share resources such as printers and CDs, exchange files, or allow electronic communications. The computers on a network may be linked through cables, telephone lines, radio waves, satellites, or infrared light beams or wireless media.

Depending upon the geographical area covered
by a network, it is classified as:
– Local Area Network (LAN)
– Metropolitan Area Network (MAN)
– Wide Area Network (WAN)
– Personal Area Network (PAN)

Now let’s dive deeper into LAN and WAN

Local Area Network or LAN. Local area network resides within a small geographic area. The network is managed by and belongs to single organisation and the distance separating the hosts is relatively small. A LAN is used to connect the computers and other network devices so that the devices can communicate with each other to share the resources, data files, software, e-mail and access hardware such as printers, FAX etc.,PC’s, laptop in an office / college. The size of LAN is usually small. The various devices in LAN are connected to central devices called Hub or Switch using a cable.

It’s also possible to have a computer network where the networks and the hosts are very widely distributed geographically. In that case we are talking about a Wide Area Network or WAN. A wide area network is a group of interconnected LANs, Local Area Networks, that are separated geographically. For example, a company can have offices at different cities. Sometimes user from one city needs to access some data that is located on a server in another city. To make that possible we’ve connected them in some way so that these local area networks are inter-networked together, making a very large inter-network or a wide area network.Computers connected to a Wide Area Networks are often connected through public networks, such as the telephone system. They can also be connected through leased lines or satellites.

The largest WAN in existence in the world is the Internet
Generally WAN is a collection of a large number of LANs connected to each other, which allows transfer of data between different LAN network.
A daily life example of home router and internet sharing can simply explain the interconnection between LAN and WAN .Router is connected to WAN and we connect many devices to each other These devices are in a LAN.

Consider a small company having a single branch and many departments within the same branch. There are several devices such as printers, fax machines ,personal computers and many more required for a company to work smoothly. These devices are to be interconnected. This is done using switches and Hubs. Now they all are in LAN. They can share files, printers and software data etc. But if the company decides to open a new branch at a remote location, then there is a need to establish a connection between the two branches. The connection can be established with the help of Network service providers and it will be a WAN. Still, the devices in a particular branch are in a LAN network. If a system among may from one branch wants to communicate and send data to a system which is in the remote branch we can’t actually connect them one to one directly because next moment another system may need to connect to another system from a remote branch and then it will be uncomfortable to connect these many system using one to one connection So here comes in picture two LAN networks one for each branch and connection between these two remotely existing branches can be referred as a WAN.

So there is a need of LAN for Every WAN to work. But the opposite may not be true always. If we don’t require a connection between two remotely spaced branches of a company or else we require a connection within the campus for data sharing then WAN has no existence.

So we can now come to the conclusion that..

Every WAN is with LAN …But Every LAN may or may not be with WAN