The Internet Connection of our home’s need some basic devices, protocols and steps. In this article, we will see how our small networks connect to the Internet. For detailed explanation of the network protocols or concepts here, you can check the related article on ipcisco.com.
In an Home Network or in Small Business Networks, basically a Home Router is used for Internet Connection. This Home Router acts as the gateway between the local users and the Service Provider that provides Internet connection.
Home Router has multiple ports on it for local users that are connected to the router with cables. There is also wireless access in this routers, that local users in the coverage area can connect to the router.
To be in Internet, every device needs to have an IP address. These IP addresses are the address of the local device and it must be unique in the Internet. The unique IP addresses are Public IP Addresses and very limited. These IP addresses are also very expensive.
To overcome this issue, NAT (Network Address Translation) is used in Home Routers.
Home Router receives an Public IP address from the Service Provider. It is known as with this IP addresses. But in the local network, it assigns the Private block IP addresses to the local users. Home Router translate Private IP addresses to Public Address with NAT and Internet Connection is established.
Public IP addresses are the unique addresses on Internet. These Public IP addresses are assigned from IANA (Internet Assigned Numbers Authority) from all over the world. IANA assign these addresses to Service Providers and Service providers give these addresses to the networks that purchase Internet Service from them. And this assignation is done according to network requirements and size.
Home Networks do not know IANA. Always Service Providers assign IP addresses to the Home Networks.
Private Block IP addresses are used inside the network. These addresses are not routable in the internet and can be used in any network at the same time in the World.
What are these Private IP block that are assigne to local users by Home Router? These Private addresses are :
• 10.0.0.0 – 10.255.255.255
• 172.16.0.0 – 172.31.255.255
• 192.168.0.0 – 192.168.255.255
These IP addresses are given to your Home Router by DHCP Server dynamically or you can manually configure this. If DHCP Server is assign your local device an IP address, your local device is a DHCP Client.
You can also check Subnetting Cheat Sheet to use a correct subnet for your networks.
Home Router use NAT to overcome limited Public Address usage. Here, there are two solutions or NAT types. One of them is called NAT(Network Address Translation) as its name and the other is called PAT (Port Addres Translation).
NAT(Network Address Translation) provides one to one translation of IP addresses. One local device provide one Public IP address. For this NAT type, you need to have a Public IP address pool. This is not efficient.