| Behind all the names on the urls of Internet | | | | The other popular usage of the local host IP |
| websites are a series of numbers called IP | | | | address are gaming servers, which are |
| (Internet Protocol) addresses. IP stands for | | | | interconnected to local hosts. By using the local |
| Internet Protocol, and constitute the primary | | | | hosts, the process and the flow of information |
| network layer for use on the Web. | | | | becomes more streamlined and efficient. |
| The 127.0.0.1 IP | | | | Because it functions as a loopback, this IP address |
| This particular IP address, also called a local host, | | | | cannot be used in any network element or node. |
| is the basis for which loopback network | | | | Testing the Loopback Properties of 127.0.0.1 |
| connections are processed. Loopback means going | | | | You do not need to be a computer programmer |
| back, and that is what 127.0.0.1 does, because it is | | | | to test the loopback function of this address. You |
| the address of your machine. Using telnet, ftp, or | | | | can go to the command prompt of your |
| try in any way to get to 127.0.0.1, you will be | | | | operating system, and at the c:\ type the |
| transported back to the host machine, yours. | | | | following: "ping 127.0.0.1". After hitting the Enter |
| However, it is only the initial three numbers (127) | | | | key, you will get an answer like "Reply from |
| that are needed; use any number combination | | | | 127.0.0.1...". |
| with 127 and the result will be the same. | | | | If you type in "ping localhost" instead of the |
| A frequent joke among programmers is to get | | | | numbers, the result would be the same, as |
| the greenhorn to connect to this IP address. | | | | localhost and 127.0.0.1 are the same. |
| However, in reality the IP address has serious | | | | You can also try it on telnet: assuming that the |
| functions. | | | | computer assigned to you has the name "Dan" |
| Uses and Purpose | | | | you will get the following result: |
| There are several practical uses for this IP | | | | # telnet 127.0.0.1 |
| address. The most common example would for a | | | | Trying 127.0.0.1... |
| software developer or network systems | | | | Connected to dan |
| administrator to try out new applications or | | | | Escape character is '^]' |
| experiment with unique set ups. This can also be | | | | Currently IPv4 is the standard in use on the |
| used by programmers who design software that | | | | Internet today. Aside from 127.0.0.1, other |
| talks to each other through the computer. | | | | reserved addresses are 10.0.0.0/8 (for private |
| This IP address is also used for beta testing a | | | | networks), 169.254.0.0/16 (for link local), |
| host of web applications, from Java applets, | | | | Others are 192.88.99.0/24 (relays from IPv6 to |
| Active X controls to web browsers. | | | | UPv4), 255.255.255 (for broadcast), 224.0.0.0/4 |
| It usually begins with the client sending out a | | | | for Multicasts (former Class D network), 240.0.0.0 |
| message to server, which would be possible only | | | | 4 for Class E Network, 192.0.2.0/24 for |
| if the 127.0.0.1 address is used. The result would | | | | Documentation and example code and 198.18.0.0 |
| be, if a web browser were to relay the request, | | | | 15 for Network benchmark tests; 172.16.0.0/12 is |
| a return to the host page of the site | | | | also used for private networks. |