Support for multisegment packets relieving the network stack of unnecessary copy operations when assembling packets for transmission.
No-copy receive and transmit. Only small packets are copied on reception because creating a copy is more efficient than allocating a new buffer.
TCP, UDP and IPv4 checksum offload (receive and transmit).
Support for TCP/IPv6 and UDP/IPv6 checksum offload.
Makes use of the chip's TCP Segmentation Offload (TSO) feature with IPv4 and IPv6 in order to reduce CPU load while sending large amounts of data.
Fully optimized for Mountain Lion, Mavericks and Yosemite (64bit architecture) but should work with Lion (only 64bit) too, provided you build from source with the 10.7 SDK.
Wake on LAN support.
VLAN support is implemented but untested as I have no need for it.