Private and Public IP Addresses: What’s the Difference?

Internet Protocol (IP) addresses areusually of two types:Public and Private. If you have ever wondered to knowwhat is the difference between a public and a private IP address,then you are at the right place.In this post I will try to explain the difference between apublic anda private IPaddressin layman’s terms so that it becomes simple and sy to understand.What are Public IP Addresses?A public IP address is assigned toevery computer that connects to the Internet where chIPis unique.In this case, there cannot exist two computers with the same public IP address all over the Internet. Thisaddressing scheme makes it possible for thecomputers to “find ch other” online and exchange information. User has no control over the IP address (public) that is assigned to the computer. The publicIP address is assigned to the computerby the Internet Service Provider as soon as the computer is connected to the Internet gateway.A public IP address can be eitherstaticordynamic. A static public IP address does not change and is used primarily for hosting web pages or services on the Internet.On the other hand,a dynamic public IP address is chosen from a pool of available addresses and changes ch time one connects to the Internet.Most Internet users will only have a dynamic IP assigned to their computer which goes off when the computer is disconnected from the Internet. Thus when it is re-connected it gets a new IP.You can check your publicIP address by visitingwww.whatismyip.comWhat are Private IP Addresses?An IP address is considered private if the IP falls within one of the IP address ranges reserved for private networks such as a Local Ar Network (LAN). The Internet Assigned s Authority (IANA) has reserved the following three blocks of the IP address space for privatenetworks (local networks):10.0.0.0 – 10.255.255.255(Total Addresses: 16,777,216)
172.16.0.0 – 172.31.255.255(Total Addresses: 1,048,576)
192.168.0.0 – 192.168.255.255(Total Addresses: 65,536)Private IP addresses are used for ing the computers in a private network including home, school and business LANsin airports and hotels which makes it possible for the computers in the network to communie with ch other.Say for example, if anetwork Xconsists of 10 computers, ch of them can be given an IP starting from192.168.1.1to192.168.1.10.Unlike thepublicIP,the administrator of the privatenetwork is free to assign an IP address of his own choice (provided the IP falls in the private IP address range as mentioned above).Devices with private IP addresses cannot connect directly to the Internet. Likewise, computers outside the local network cannot connect directly to a device with a private IP. It is possible to interconnect two private networks with the help of arouter or a similar device that supportsNetwork Address Translation.If the private network is connected to the Internet (through an Internet connection via ISP), then ch computer will have a private IP as well as a public IP. Private IP is used for communiion within the network where as the public IP is used for communiion over the Internet. Most Internet users with a DSL/ADSL connection will have both a private as well as a public IP.You canknow your private IP by typingipconfigcommand in the command prompt. The that you see against “IPV4 Address:” is your private IP which in most cases will be192.168.1.1or192.168.1.2. Unlike the public IP, private IP addresses are always static in nature.Common Myth about Private IP Address:Most people assume that a private IP isthe one used for stlth Internet activities and hence cannot be detected. But this is NOT TRUE!.Unlike what most people think, a private IP address (unlike the private telephone ) is just like any other IP address that belongs to a private network. In rlity, there is no public IP address that is impossible to trace as the protocol itself is designed for transparency
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