A method of securely routing data traffic between communication networks. In an integrated security device, a host router supports a virtual router that peers with VRF (virtual routing and forwarding) instances associated with participating networks on the host router. Each VRF instance preferably runs its own dynamic routing protocol and determines when received data traffic may be directly forwarded from one network to another and when it must be forwarded to an OE (offload engine) for enforcement of security policies or NAT (network address translation) processing.