One of the most frustrating features of working in a simulated environment is generating test traffic to pass though your simulated network. The job of generating test traffic is where the little application VPCS (Virtual PC Simulator) comes into its own.
VPCS is a lightweight application that can simulate up to nine computers from a single command line interface. From the command line you can ping and traceroute to GNS3 devices, and even send streams of UDP and TCP packets if you wish.
In this section, I will show you how to use VPCS in your GNS3 environment to expand your network to look like the following figure.
Step 1: Add host devices to your topology
Start by opening GNS3 and loading the Basic2Routers project ...