Trate is a free software to support Peer-to-Peer communication across Network Address Translator (NAT).Trate allows other applications - almost all applications(BitTorrent,Web server etc) - to automatically create dynamic connections between two or more peers behind two or more separate NATs and firewalls.

That means machines behind a NATed firewall (e.g. An enterprise firewall, or a home router) can connect to each other through the help of Trate. More specificly, it can accelerate your BT downloads, allow you running your Web or FTP site behind a firewall with a private IP address, or help any application which needs to listen to a port.