Difference Between LAN and WAN

LAN vs WAN

When it comes to networking, knowing the difference between LAN and WAN is very important. A LAN is a computer network limited to a small geographical area such as home,office and school while W AN is a network across a large geographical area such as a city, country or the whole world. Internet is an example for a WAN. A local area network uses technologies like Ethernet,Wi-Fi。LAN的特征是高速，较少的错误，易于故障排除和低成本。WAN通常基于租赁线路，因此它们的成本更高，而速度却更低。同样，由于复杂性，错误量很高，并且很难维护。

What is LAN?

LAN, which refers to local area network, is the name given to a computer network spread in a limited geographical area. So computer networks found in a limited area such as a home, school, office building can be identified as local area networks. Both wired and wireless media can be used for interconnections where Ethernet over twisted pair and Wi-Fi are the most used methods for LAN. Since limited to a small area, the cost for the network is relatively low. Also, the speed is high for instancegigabit Ethernetcan provide about 1Gbps speed. Nowadays, when higher speed is necessary, optical fiber cables are used for LANs, but it is a bit costly. Also, due to the nature of the network, the errors and connection problems are relatively less and troubleshooting is easier in LANs.

What is WAN?

Wan, which refers to wide area network, is a computer network spread over a large geographical area. A network across a city, a country or a network that covers the whole world are identified as WAN. For example, internet that connects devices across the globe is a WAN. A WAN can be used to interconnect several LANs, as well. For example, consider a bank network. Each bank building will have a LAN and across the country there will be several branch buildings. So, the WAN will interconnect these branch LANs throughout the country. The most used method for connectivity is leased lines. A leased line is a telecommunication line laid between two or more locations by an internet service provider on behalf of a customer usually for a monthly rental. Therefore, a WAN is much costly when compared to LAN and also the connection speed is much less when compared to LAN. Also, due to the large distances, errors and connection problems are relatively high and troubleshooting is difficult. Protocols such asPPP, ISDN, X.25,Frame relay,IPv4和IPv6用于WAN。

What is the difference between LAN and WAN?

• A LAN refers to local area network while WAN refers to wide area network.

• A LAN is limited to a small geographical area such as a building, home, school and office. A WAN spreads across a city, country or even the whole world. Internet is an example for a WAN.

•像以太网和无线局域网使用技术。Leased lines are required for WAN.

• The transmission speed in LANs is high. However, transmission speed of WAN is usually low.

• The cost for a LAN is lower than the cost for a WAN.

• The amount of errors in a LAN is much lesser than the amount of errors in a WAN.

•LAN中的问题比WAN中的问题容易排除。LAN的维护成本要比WAN的维护成本要小得多。

•LAN中的拥塞通常比WAN的拥塞要小。

• A LAN can be created with simple network devices such asswitches and hubs。However, a WAN needs devices such as路由器和网关。（但是今天兰斯也包含了几个subnetswhere they will have routers and gateways too.)

•LAN通常由一个人或公司拥有和控制。另一方面，WAN由多个政党拥有和控制。

Summary:

Wanvs LAN

A LAN is a computer network across a limited area such as a home, school and office. A WAN is a huge network , which even interconnects the LANs spread across a city, country or even the whole world. Internet is also a WAN. A LAN is a small system hence it is much faster, less costly, and the number of errors is less. They are easy to troubleshoot and maintain. On the other hand, WANs require leased lines to be laid probably by contracts with ISP and, therefore, the speed is less and the cost is high. Also, since a WAN is a large system, the amount of errors can be high while the troubleshooting is difficult making maintenance more difficult.

Image Courtesy:LAN-WAN Schemeby Gateway_firewall.svg: Harald Mühlböck derivative work: Ggia (Gateway_firewall.svg) [CC-BY-SA-3.0或者GFDL]，通过Wikimedia Commons