What Is A Local Area Network (LAN)?

learninmypc

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Put simply, a Local Area Network (LAN) is a group of computers and other devices that are connected together over a network and are all in the same location—typically within a single building like an office or home. But, let’s take a closer look.



What is a LAN? FULL ARTICLE
 
A LAN, is always an IP address with address segments of:
  • 10.0.0.0 - 10.255.255.255, or
  • 172.16.0.0 - 172.31.255.255, or
  • 192.168.0.0 - 192.168.255.255
are commonly referred to as "non-routable" addresses, because there are millions of these and they are not unique on the Internet as is, say the Google Public DNS at 8.8.8.8

The key feature that allows this magic is NAT (Network Address Translation), where all of your LAN systems appear to the Internet as coming from your ISP assigned, routable PUBLIC I.P.
 
A LAN, is always an IP address with address segments of:
  • 10.0.0.0 - 10.255.255.255, or
  • 172.16.0.0 - 172.31.255.255, or
  • 192.168.0.0 - 192.168.255.255
are commonly referred to as "non-routable" addresses, because there are millions of these and they are not unique on the Internet as is, say the Google Public DNS at 8.8.8.8

The key feature that allows this magic is NAT (Network Address Translation), where all of your LAN systems appear to the Internet as coming from your ISP assigned, routable PUBLIC I.P.
You're the first person I thought of when I saw this article. Thanks for your input :)
 
HMM; LAN -- a small number of of systems or devices which can communicate with each other.

IP addresses are in the range:
  • 192.168.x.y
  • 176.16.x.y
  • 10.x.y.z
Depending upon the configuration, these devices may or may not be able to communicate with the Internet. Likewise, by configuration choices, the Internet may not access them.

In addition, a LAN typically doesn't have a server unless it JOINS a domain controller like Exchange+LDAP.
 
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To add to the above-- a LAN is usually setup by two methods, either using a Layer 2 Switch or an AP which Bridges to a LAN Wirelessly.

Each port on a layer 2 switch has its own Collision Domain unlike a Hub which only has one Collision Domain. (Traffic in one collision domain is broadcasted to everyone which is why CSMA/CA CSMA/CD had to be developed.)

I have a LAN at home so where is my switch?

Simply put a modem which is provided by the ISP is a multifunctional device. It incorporates a modem,router and a Layer 2 switch. This switch is available on the backside of the modem usually being Port 2-5 AKA LAN Ports on the modem.


 
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