LAN is abbreviation for Local Area Network and WAN is abbreviation for Wide Area Network . The two networks are generally classified on the basis of their coverage area . As the naming conventions suggest, Local Area Networks (LAN) are for smaller, more localized networking ; in a home, business, school, inside a campus etc. whereas Wide Area Networks (WAN) cover larger areas, such as cities, and even allow computers in multiple geographic locations to connect.

Difference between Local Area Network and  Wide Area Network

What is LAN?

Basically a Local Area Network is designed using a shared medium. LAN connections generally send information through a set of devices owned and often controlled by a single person or organization. This means many end users will be using the same cable and will be connected to each other over the same cable in some network topology like a bus or a ring. So the data packets can be seen by everyone on a Local Area Network. Its the job of a Network Interface Card (NIC) to filter out the packets and receive only those packets meant for its own host.

Every NIC has a hardware address that's known as a MAC, for Media Access Control. MAC Address is a physical address which works at Data Link Layer . Local Area Network ethernet communications are actually done using the MAC address that the machines actually respond to. Even with TCP/IP, DECNET, MOP, LAT, IPX, SPX and other protocols , they still map those addresses to a MAC address. This type of relationship also applies to token ring communications and other low level protocols. Private addresses are unique in relation to other computers on the local area network. Routers are found at the boundary of a LAN , connecting them to the larger Wide Area Network.

What is WAN?

Wide Area Network ( WAN )connections can go through multiple devices owned and controlled by multiple companies and organizations. It allows you to access, communicate, share the data and devices sync with the world wide web (www) or internet, this is all done with the DNS servers that keeps the records of computers, servers hosted globally for different services.

WAN spans over multiple geographic locations , which is composed of multiple Local Area Networks connected together using routers. It's very difficult to maintain because of wider geographical area. It uses layer-3 devices like routers, multi layer switches. The packets are routed in a store and forward manner. This means the routers receive packets lined up in a queue and forward them to the next neighbouring router by seeing the destination address. Since Wide Area Networks (WANs) involve 3rd party service providers, WAN networks are less reliable and secure.

LAN Vs. WAN  Local Area Network (LAN) Vs. Wide Area Network (WAN)

LAN - WAN Differences

Local Area Network (LAN) Wide Area Network (WAN)
Typically owned, controlled, and managed by a single person or organization. Not owned by any one organization but rather exist under collective or distributed ownership and management over long distances.
Using Layer-2 devices like switches and bridges. Layer-1 devices like hubs and repeaters. Using Layers-3 devices Routers, Multi-layer Switches and Technology specific devices like ATM or Frame-relay Switches etc.
High data transfer rate. Lower data transfer rate compared to LANs.
Tend to use certain connectivity technologies, primarily Ethernet and Token Ring Tend to use technologies like MPLS, ATM, Frame Relay and X.25 for connectivity over longer distances
Experiences fewer data transmission errors Experiences more data transmission errors as compared to LAN
High bandwidth is available for transmission. Low bandwidth is available for transmission.
Transmission medium used in LAN is co-axial or UTP cable. WAN uses PSTN or satellite link as a transmission or communication medium.
Less congestion More congestion

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