LAN and wide area networks (intranet and extranet)

Build a LAN When you have time to see if you can use it.

The so-called intranet is what we normally call LAN. A local area network is a closed computer group that is constructed from more than 2 computers with network cables and other networking equipment in a fixed geographic area. It can be 2 computers between neighbors or 1000 computers in a 100-storey building. The local area network can be isolated and run independently, or it can be connected with the external network.
  The so-called external network, that is, WAN. is a network collection with a very large geographical span. It is comprised of countless local area networks + standalone servers. Note that the LAN described here can be either a small WAN or a local area network.
  In fact, on a scale, it is difficult to distinguish between LAN and WAN because the size is relative. So. The difference between a real LAN and a WAN is achieved by an IP address.
  Any computer that wants to surf the Internet must have a unique IP address on the network. Within the LAN, this IP address is unique. But on another LAN, this IP address can still be used.
  Network A has an IP address of 192.168.1.231 client, Network B can also have a computer with the same IP. So. We say that these 2 machines are in 2 LAN respectively. But within the WAN, all IP addresses are unique. The DNS server IP address of Shaanxi Telecom is 61.134.1.4. Well, this address is unique throughout the world and cannot be duplicated. This is the difference between a WAN and a local area network.

Myth 1

There are two ways of LAN creation (1) using routers to realize local area network, (2) using hubs to realize computer communication or to build local area network;
(1) The router establishes the local area network, first connect the router to the power, then connects the computer through the network cable, the computer can connect 6 desktops. Of course, LAN can also realize the wireless network link to become a LAN, through the router to create a wireless network, and then use the wireless network card to find the wireless network connection success, you can also create a successful LAN.
(2) Connect the power supply via the hub, then connect via the network cable hub and computer.
If the computer needs to surf the internet need the cat dial-up connection on the router can be online, hub and then connect the router, then the local area network of the hub can also be connected to the Internet.

Myth 2

Routers are divided into LAN ports and WAN ports. If we want to set up a non-networked LAN, directly to the need to put in a local area network computer, using network cables are plugged in LAN port.

If we are to establish a networked LAN, then we need to be able to surf the Internet network cable, plug in the WAN port, while the need to establish the LAN in the computer's network cable, are plugged in the LAN port.

After the line is plugged in, it needs to be adjusted in the router, modify IP and network segment settings, and so on. The general router default IP is: 192.168.1.1, user name and password are: admin, admin.

After entering the main page of the router, click Set up the route, then follow the steps, step-by-step setup, and finally restart the router. Then on the homepage, you can automatically get the IP, you will be able to surf the Internet.

If you need to set up a network segment or DNS, you need to set it in Dynamic DNS and set it to an IP that is not on the same network segment as the current one. Tp-link routers also have the ability to set up a wireless network and, if needed, can be set as prompted.

At this point, the computer can click on the Web page, if you are not prompted to connect to the network, check the Router Settings home page, there is no automatic access to IP. If the IP is not automatically acquired, it is necessary to reset the IP DNS until the IP can be automatically acquired to be able to access the Internet.

LAN and wide area networks (intranet and extranet)