Why private and public IP addresses for IPv4 addressing is necessary

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In the IPv4 version there is the existence of the private and the public addresses. A private IP address is defined as a network that uses mainly a private IP address space using a standard that is specifically laid down by the RFC 1918 whereas the public network uses the public IP address space.

Private IP addresses

Private addresses are commonly used in offices, homes and in local area networks since they are not globally delegated and are mainly designed to reduce IPv4 address exhaustion. Private addresses are not usually allocated to any specific organization and this makes them quite easy to access since one does not need approval from the regional access authority to have access to it. Its connection to the internet is also quite simple because it uses either a translator from the network address gateway or a server that originates from proxy.

In order to reserve the private address in the IPv4 address, the Internet Assigned Numbers Authority allocated three categories of the private address:

  • The 24 bits block that has a host size of 24 bits and common in the single class network.
  • The 20 bits block which is made up of the 20 bits of host size and identified in the group B network.
  • The 16 bits block has a 16 bits host size and of the third class of networks.

There is another type of the private networking that mainly uses the link local address and in IPv4; this address is usually included in the RFC 6890 and the 3927 model. The link local address acts as a device of automatic configuration in conjunction with the Dynamic Host Configuration Protocol in order to serve its purpose. The link local address in the IPv4 ensures that there is no collision between the subnets especially in the Ethernet network.

Importance of the private internet protocol addresses in the IPv4

One of the benefits is that private IP addresses are largely residential networks due to the fact that most residential cases only one routable IP address therefore making it easy to connect to the internet. The addresses are also used in the business networks where they are connected to certain to the SOCKS proxy that restrict other users from using that particular network, in other words the private IP address enhances security in most of its settings.

The private IPv4 address has a special feature of their ability to merge with each other in spite of it being a special characteristic; it comes along with a disadvantage. The idea of merging increases its size but this risks the idea of duplication of addresses on most of the devices and as a result collision between the hosts from the same network occurs.

Public IP addresses

This type of address is usually issued by the Internet Service Provider and as a result used in large field of operation because of their wide range in the first octet and due to the fact that they  be easily accessed through the internet. The public IP address is also an identifier in the IPv4 whereby it is assigned a virtual router and assists in cloud computing system.

The public IP address allows any two computers to identify each other that is it one uses a computer, it usually has a special address that can be identified by its customers when the computer is in use.  This is important in the IPv4 case since the server is able to identify the host and send the correct response and check whether the system is exposed to any risk.  There are two types of the public IP address that are directly related to the IPv4 address.

  • Static IP address

This type of IP address is used to host websites and services on the internet and it is applicable for those who use the voice over IP situation because it makes communication to be quite simple.

  • Dynamic IP address

This address is usually chosen from the available IP addresses and is usually not the same since it varies depending on the users using the internet. It is considered to be the standard address since it is found in most computers when the user uses the ISP services.

Importance of the public IP address in IPv4 addressing:

Its ability to identify the location where a certain activity has been carried out especially online has led to improved security of the contents and also made it easy to track down the sources because every public IP address has a special code allocated to it by the Internet Service Provider. The use of the internet has also given rise to a lot of scammers who tend to benefit from others but the introduction of the public IP address has reduced the number significantly since it has become quite easy to track them down.

When it comes to communication, the public IP address ensures that there is sufficient flow and helps in avoiding of collision of the two hosts from an identical IPv4 that have been merged together because of their limited space. It provides the required route for the IPv4 address to reach its required destination taking the shortest time possible and this is an advantage because it saves on time.

Comparison of private and public IP addresses in IPv4

There are only three types of IPv4 in the private IP address while in the public IP address there are a number of them because the public IP address is widely used and applies in larger fields unlike the private IP address that is commonly used in small enterprises and homes. On the other hand it is quite easy to acquire the private than the public one since there are no formalities required.


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