Virtual network technologies

Network virtualization is when software acts like network hardware and it is accomplished by using logically simulated hardware platforms.

Virtualization of networks is not a new concept, and we can find one of the first implementations in the mid-1970s with virtual circuits on X.25 networks. Later, other technologies also started using virtual concepts, such as Frame Relay and ATM, but they are now obsolete.

Loopback interfaces were based on electronics where loopbacks are used to create electric loops for the signal to return to its source for testing purposes. In 1981, the IETF referred to the reserved address range 127.rrr.rrr.rrr with RFC790, which also outlined 32-bit IP address space classes. In 1986, with RFC990, the address range 127.rrr.rrr.rrr was officially called loopback. Today, this IP range is used in computer platforms to designate the localhost IP address of the computer when using the TCP/IP stack (for example, 127.0.0.1)

Another...