GNS3 is a graphical network simulator that allows you to design complex network topologies.
You may run simulations or configure devices ranging from simple workstations to powerful Cisco routers.
Build, Design, and Test your network in a risk-free virtual environment and access the largest networking community to help.
The best bang for your marketing buck with a concentrated group of over 2 million network professionals who come to the GNS3 community to connect every day.
Put your goods to the test to find out how good they are, and get feedback from the GNS3 pros, whose feedback matters the most.
Simple Port Forwarding works with webpages and not directly with your router making it a safe program to use. Supports 52 Languages and 2600+ routers. Portable version also available.