What is NAT (Network Address Translation)

The proliferation of wired and wireless technologies has given rise to the possibility of multi-access options for mobile, multi-homed hosts. Enabling multi-access techniques improves fault tolerance by adding redundancy to network connections. For example, if a host is enabled with two network interfaces connected to the Internet via two different Internet service providers (ISPs), the failure of one network will not stop data transmission. The host will be capable of continuing the data transfer by switching over to the other network. Furthermore, if both networks are active at the same time, but packets experience higher delay and congestion on one path, multihoming facilitates the possibility of switching over to the network path offering better performance. However, the key factor in attaining the benefits of multihoming is to ensure that the handoff or switch over from one network interface (or a network path) to the other active interface should take place with minimal interruption. Stream control transmission protocol (SCTP) provides support for multihoming by allowing a single connection between two nodes to hold several IP addresses simultaneously.