Home Network IP Address Allocation
and Internet Connection
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 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
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 IP Addresses
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.
NAT(Network Address Translation)
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.
PAT (Port Addres Translation) provides many to one tranlation of IP addresses. Here, one Public IP address is used for many devices in the local network. And Router also maps the Port used by local user.
With NAT and PAT, the Service Provider side of the Home Router uses Public IP Address and the local user side uses Private IP Address. In every local device, as a Gateway IP address, Home Router local user side IP address is given. Because, local users’ Gateway is Home Router.
DHCP (Dynamic Host Configuration Protocol)
IP address allocation can be done manually. But this is not efficient. To overcome this issue, DHCP (Dynamic Host Configuration Protocol) is developed. DHCP is the protocol that provides IP addresses to the local devices in the same network from the preconfigured IP address Pool.
DHCP has two sides. These are DHCP Server and DHCP Client. In an Home Network DHCP Server is your Home Router. DHCP Clients are the local devices. Home Router works as a DHCP Server and gives Private IP address to the local devices.
DHCP does this job dynamically. It assigns an IP address to the lcoal device and local device uses this until it expires. Before the expire it gets the same or a different IP address form the Home Router.
To sum up Home Network and Internet Connection, there are four main terms :
• Public IP
• Private IP
Service Provider gives you a Public IP address. DHCP associate you a Private IP address. And NAT translates these two IP address. After this, you are on Internet!
This is basically our Local Internet Connection sn its Components. For detailed explanation of each part, you can check the related article series..
For the Other Parts of these article series, you can check the below lessons :
Fot IPv6 Addressing, you can check the below lessons :