Network emulation is used for testing the performance of real applications over a virtual network. It is the act of introducing a device to a test network that alters packet flow in such a way as to mimic the behavior of a network. Netem is a network emulator tool provides functionality for testing protocols. It will emulate the network properties of wide-area networks.
Netem is already enabled in the kernel and a current version of iproute2. The netem kernel component is enabled under: