3Com 3CR990-TX-95, 3CR990-TX-97, 3CR990SVR97, 3CR990SVR95 manual Using Windows 2000 Offload Features

Using Windows 2000 Offload Features 73

miniport icon name. If a miniport is associated with an ungrouped NIC, you can identify the NIC by its MAC address as follows:

1In the Network and Dial-up Connections window, right-click the miniport icon and select Properties from the menu.

2In the DynamicAccess Properties window, click the General tab.

3In the General tab, move the cursor over the miniport name. (Do not click the name.)

After a short pause, the MAC address of the associated NIC appears in a pop-up window.

Using Windows 2000 Offload Features

The 3CR990 NIC supports Windows 2000 offload features in an IP environment. The Windows 2000 offload features are designed to enhance the Windows 2000 operating system capabilities by off loading key TCP/IP networking and security tasks from the Windows 2000 operating system:

■IPSec Offload—reduces CPU utilization by allowing the 3XP processor and a crypto chip on the NIC to perform data encryption operations.

■TCP Segmentation Offload—reduces CPU utilization by allowing the 3XP processor on the NIC to perform segmentation of TCP packets.

Windows 2000 does not allow IPSec offloads and TCP Segmentation offloads for the same session. Though all offload types may be enabled, TCP Segmentation offloading will not occur during an IPSec session.

■IP and TCP Checksum Offload—reduced CPU utilization by allowing the 3XP processor on the NIC to perform the checksum calculation of TCP/IP and UDP/IP packets.

■802.1p Packet Priority Offload—reduces CPU utilization by allowing the 3XP processor on the NIC to perform the insertion of the 802.1Q tag header into the packet.