IP address, in general, are classified into Public and Private IP Addresses. A Private Network that works behind the router uses the Private IP Address. Any Local Area Networks (LANs) in Home, Office or Organization uses them for addressing.
Unlike Public IP these private spaces are not allocated to any specific person and they can be used by anyone without the ISPs Approval. The Standards set by RFC 1918 for IPv4 and RFC 4193 for IPv6. Quite a few times these are cited to as local IP address.
List of Private IP Address
The Private IP Addresses range is reserved by the Internet Assigned Numbers Authority (IANA) which is the worldwide single organization that allocates and assigns IP Address in a systematic and consistent manner. Below is the list of Private IP Address.
|S.No||IP Address Range||Classes||Number of Addresses|
|1||10.0.0.0 – 10.255.255.255||Class A||16,777,216|
|2||172.16.0.0 – 172.31.255.255||Class B||1,048,576|
|3||192.168.0.0 – 192.168.255.255||Class C||65,536|
Class A has a total of 16 million addresses, Class B has 1 Million Addresses and Class C has 65,536 Addresses.
Excluding three, another range of Private IP addresses -169.254.0.0 to 169.254.255.255 which can be allocated only through Automatic Private IP Addressing (APIPA).
In April 2012, Carrier grade NAT similar to Private but doesn’t come under either private or public is only to be used with internal operations of carrier networks.
How to find your Private IP Address?
Finding your Private IP address is easy as a pie. In every platform like Windows, Mac, Linux one can open the Command Prompt or Terminal to get the info quickly. Below in the Windows, Click on Start > Search ‘cmd’> Enter. Once inside type
'ipconfig'. Press Enter to get the Private IP Address.
Why do we need Private IP Addresses?
As we all know Public IP Address is exhaustible and since we are running sparse using Private IP address allows the devices in the home or an organization to use an entire set of addresses which allow access to the network without utilizing the public IP address.
Let’s be clear with an example. If you and your neighbor or anyone across the globe can use IP address 10.0.0.0 or 172.16.0.0 or 192.168.0.0 and its consecutive IPs and assign to the devices in the network via DHCP.
Each and every network having hundreds of devices using the same IP address doesn’t matter at all since they don’t communicate directly.
How can Private IP Address Connect to the Internet?
Direct Internet Connection is not available to devices that are present in a Private IP but they can communicate internally to any devices on their local network. Same is applicable to computers outside the network they cannot communicate with any device inside a Private IP.
A router or any device which supports Network Address Translation(NAT) is used for the connection to the internet and the network. Since NAT hides the Private IP by using the Routers Public IP for communication adding a layer of security to the network.
Reserved vs Private IP Addresses
Reserved IP addresses stand for even more restricted IP addresses that cannot be used for communication, unlike the Private IP addresses which are used as the local network.
127.0.0.1 is called the Loopback address and the famously used reserved IP address. The entire range 127.0.0.0 – 127.255.255.255 is reserved for loopback address but majorly they are not used in the real world.
Loopback is a testing mechanism of the network adapter. 127.0.0.1 doesn’t deliver any messages to the network that are sent over it.
Including to above, another reserved loopback range is 0.0.0.0 to 0.255.255.255. If you are able to Assign any node on this range it, they won;t be able to communicate to the Internet properly.