A system and method is provided that enables older legacy guest operating systems like Windows NT 4.0 and Windows95® to take advantage of newly developed NDIS Intermediate (IM) drivers that support firewalls, quality of service, IP security, intrusion detection, and other functionality for monitoring/filtering incoming and outgoing network traffic in contemporary host operating systems such as Windows XP operating in a virtual machine (VM) environment. The invention thus makes such older legacy operating systems less susceptible to Internet viruses, and worms, network denial of service (DOS) attacks, and the like. For each Virtual Network Interface Card (VNIC) in a guest VM, a corresponding VNIC is created on the host OS, and a point to point connection is established between the guest and host VNICs. The NDIS IM drivers bind themselves on top of the host VNIC and effectively place themselves as a filter on the point to point connection.