nfsrvfilter is a server side driver, allowing to control access and filter IP traffic on a gateway host. TCP connections and UDP packets directed to other hosts via gateway with installed driver can be filtered by redirecting them to local proxy using network address translation. When the filtering is enabled for TCP and UDP, the solution works as a transparent proxy for the filtered traffic.
The solution allows filtering (modifying) incoming/outgoing TCP connections and UDP datagrams. It is possible to filter the specified subset of connections/datagrams, restricted by filtering rules.
The filtering driver is implemented as WFP filter on the top of TCP/IP stack. In effect it automatically supports all kinds of TCP/IP capable network adapters: Ethernet, Dial-up/DSL/Cable modems, wireless adapters including Wi-Fi and Bluetooth, virtual adapters like loopback or VPN.
Both IPv6 and IPv4 are supported.
It is possible to control the speed of data transmission and count the traffic using flow control contexts.
The driver works in the same way on all 32-bit and 64-bit Windows operating systems
starting from Windows 8. It is possible to use 32-bit API with 64-bit driver.