In this article I describe the Private IP address in computer networking for ccna exam preparation. We learn a lot about the IP address system in computer networking and subnetting of IP address. In this section we discuss on necessity and importance of private IP address in computer networking.
IP address is the identity of any device in a network. Without IP address any device can not communicate with the network or other devices. IP is acronym of Internet Protocol. In any network the devices are identify by its unique IP address.
IP protocol works on internet layer in TCP/IP model. IP address system created by fix length binary numbers. The IP address system in computer networking is a logical numeric address alloted to devices in the network. MAC address is the hardware address and never change in any network.
The IP address can be changes for each device in a network. IP system was designed to allow hosts to communication with each other. IP system is the identity of any hardware device for communication. The IP system is of two types IPV4 and IPV6. Here in this article we discuss about IPV4 only. There is a separate article for IPV6 on this website.
Before going to explain Private IP address system in computer networking. Some terms are necessary to know which are used in IP address system in computer networking. A Bit may be either 0 or 1. One Byte is equal to 8 bits. One Octat is equal to 8 bits and. Network Address is the designation used in routing protocols for sending the data. It is basically the first address of any subnet.
Network address never used by any device. Network address is the identity of any network. Broadcast Address is used to send data to all nodes in a network. Broadcast address is the last IP of any subnet. In any network Network address and Broadcast address never assigned to any device. For example 192.168.1.3/24 IP belongs to Network ID 192.168.1.0/24 and Broadcast ID is 192.168.1.255/24.
Network Id is the IP address which use to identify the network. The first IP address of a block of IP address is known as network Id. The last IP address of the IP block is known as broadcast ID. For example 192.168.1.3/24 IP belongs to Network ID 192.168.1.0/24 and Broadcast ID is 192.168.1.255/24.
IP address is the identity of any device connected in network. The communication between different devices can be done on their identity which is IP address. The whole IPv4 address system divided in 5 classes. In three classes A, B and C some range of IP address keep reserve for private use by any device or network. IANA( Internet Assigned Number Authority) allot the private and public IP address to use on internet.
Definition of public IP address in computer networking
Public IP address are those address which are used by internetwork devices for routing protocol. The public IP address are allotted by the ISP of special requirement. When we take an internet connection the ISP allot us only a single public IP which works like a gateway for our small network. Lets take an example of our home network.
There is a single gateway allotted to us by the ISP in the modem. Behind the modem we are using multiple devices to access the internet. When we add a new device we never ask to ISP to allot a new IP address.
So the scene is that we always working with private IP address in our local network behind a single public IP address. Now lets move on the topic related to private IP address in computer networking.
Definition of private IP address in computer networking
Private IP address in computer networking are a slot of IP address which allow any organization to create their own private network. These private networks are purely creates for the related organization for personal use. A single group of IP address can be use by many organizations simultaneously. This is possible because the private IP address series does not configure in any routing table in all over the world. So the routing devices does not identify the devices which are using the private IP address in computer networking.
I hope you have seen most of devices at your home or offices are using the common IP series of 192.168.x.x . This IP series is purely allow to use for private devices. Now the question comes in picture how we access internet from these private devices. Well we go on the operation of private IP address later in this article. Now just understand that private devices can not communicate in an internetwork without routing device such as router.
Reserve IP address in comptur networking
We know the IP addresses are limited and the users are growing day by day. So some IP address keep reserved for some special purpose. These IP address does not used by any networking device.
All Network address bits are 0 denotes the network itself.
All Network address bits are 1 shows that all networks.
IP address 127.0.0.1 reserved for testing purpose locally. Any packet with header 127.0.0.1 never send to in any network.
All host address bits are 0 denotes to any host.
The host address bits are 1 denotes to all hosts.
The network and host bits are 0 denotes the default route in routing protocols.
The network and host bits are 1 denotes the broadcast for every host.
Private IP Address in computer networking
A private IP address in computer networking reserved for internal use behind a router or gateway, apart from the public. Some IP address kept reserve for private use in the network. These IP address can be use for private network only. These IP address are not use in any internet router for routing protocol. If every one need an unique IP then the IP address became short, also it is not possible.
By using private IP address small networks needs a single IP as gateway to connect with internet. Every user of a LAN can access the internet by using private IP address. NAT and PAT used for maintain the traffic via a single gateway IP address. Following are private IP address can be use for private usage.
Selection of private IP address in computer networking
You should know what private IP address is best suitable for your network. In which class your requirement complete. Selection of IP address is depends on number of network and hosts. Here Private IP address available for each class. Mostly for a small network upto 253 hosts class C private IP address used for devices. For Intranet when the location of an organization are far away class B private IP address. Since a private organization may need 15000 or more IP address for their network. The 172.20.x.x/16 series can be use. As it provides 255×255 private IP address.
The IP address 192.168.1.1 can be use by multiple local networks as their gateway. The reason behind that the router use NAT and PAT to allow access the internet between the 192.168.1.1 and the public IP allotted by the ISP. The router at other end communicate with it on public IP address. It is the task of router to communicate the private IP address with the public IP address. It means the devices lie within a local network can communicate with each other but can not access the internet without a router.
Working of private IP address from a local network
The translation of private IP address to a public address done by NAT Network Address Translation. For translation inside local IP address converted to inside Global address . In simple words we can say NAT Network Address Translation allow the local hosts to access internet with single public IP address.
Various web services accessible on particular port numbers like FTP on 21. These port numbers of various services helps to access the internet by local hosts. NAT Network Address Translation works on Network layer of OSI or TCP/IP model. For more details on the function of NAT Network Address Translation read full article here
As this article is about the Private IP address in computer networking only. So I give an overview related to the Private IP address.
I hope you found this article helpful for knowledge of networking. For any query or suggestion on this topic you may drop a comment below or contact us. Your suggestions are always welcome by our team.
