What is the meaning of this IP address 127.0.0.1?

This IP address is one of the so-called special purpose addresses which are reserved for being used on every individual computer. In fact, the 127.0.0.1 address is normally the loopback address of the computer in Internet Protocol. What the term loopback implies is the following: it is a mechanism for testing network adapters. Thus, it is important to point out that the messages which are sent to this IP address are not delivered to the network. What happens instead of delivery is that the adapter proceeds to intercept all the loopback messages and then returns them to the transfer application. Thereby, this feature is frequently used by IP applications for the testing of the performance of the network interface.

What exactly is a loopback address?

A loopback address is said to be a special Internet Protocol (hereinafter: IP) number (in this case, it is 127.0.0.1) which is chosen for a device’s software loopback interface. Also reserved for the loopback system are the addresses from 127.0.0.0 to 127.255.255.255, which in effect are utilized for the purpose of internal tests carried out on the local computers. However, this range should not be used by nodes on the Internet. Also, as with the loopback range, the address range from 0.0.0.0 through 0.255.255.255 should not be considered part of the normal Class A range. The addresses dubbed as 0.x.x.x have no specific function within the Internet Protocol system, although the nodes which are attempting to utilize these addresses will not have the capability to have a proper communication on the Internet. All in all, this is a special address, as it is conventionally the loopback address almost in nearly cases.

What is this address for?

This address is used for the aim of network software as well as utilities using the address 127.0.0.1 in order to access the TCP/IP network resources of a local computer. In fact, the messages which are sent to such loopback IP addresses do not access the LAN (which is an acronym for a local area network); instead of that, they are re-routed automatically by the network adapter of the computer and right back to the TCP/IP pile.

127.0.0.1

What is LAN?

A LAN or a local area network is what supplies groups of computers with networking means. These machines should, as a rule, be close to each other (for example, in a school, or in an office building, or even a home, which is increasingly the case). A LAN can be very useful in order to share resources such as printers, files, games as well as many additional applications. As a rule, the majority of these local area networks utilize Ethernet or Wi-Fi in the aim of providing a connection between machines. In effect, every one of the local networks can work independently (meaning, not connected from other networks). On the other hand, it can also be linked to some other networks as well as a Wide Area Network or WAN (this is a gathering of computers as well as other network resources which are linked by way of a network within a certain area – such as for example the Internet). Two computers are said to be the smallest local network, and a large network entails as many as perhaps hundreds of thousands of machines. In reality, the majority of LANs make it possible for computers to carry out communication over IP or Internet Protocol via built in support for the network operating system of every computer.

What is a private address?

This IP address is technically not a private address. These IP addresses are usually employed for local networks which can include schools, homes, as well as business local area networks, as well as hotels and airports. It is relevant to say that computers which have private IP addresses can’t be directly linked with the Internet. Similarly, those devices which are outside a LAN can’t be directly linked to a device which uses a private address. As an alternative, the accessing of these computers needs to be carried out by way of a router or some analogous machine which supports NAT (the acronym for Network Address Translation). NAT is a method which can hide private IP numbers although it it also able to transfer (in a selective manner) messages to devices, at the same time providing a level of safety to the LAN. In fact, private IP addresses were created in the aim of preventing a scarcity of public addresses which are available for subscribers as well as Internet service providers.

What then is the difference between reserved and private IP addresses?

Despite the fact that private IP addresses are on local area networks (but not the freely available and shared Internet), the addresses called reserved lack the capacity of being used in any way for standard and normal communication over networks.