TCP/IP Checksum Offload Issues
Posted on 2012-03-14
I have been troubleshooting some random performance issues regarding network throughput etc. and found something interesting. While using the wireshark I’m noticing high amount of errors - outgoing packets marked black with red Text and the note [incorrect, should be xxxx (maybe caused by "TCP checksum offload"?)].
I have noticed that I can make some changes - Control Panel->Network and Internet Connections->Network Connections, right click the connection to change and choose 'Properties'. Press the 'Configure...' button, choose the 'Advanced' tab to see or modify the "Offload Transmit TCP Checksum" and "Offload Receive TCP Checksum" values.
However, my Dell 2950 using a Broadcom BCM5708C NetXtreme II GigE driver with
IPv4 Checksum Offload (Tc/Rx enabled) . I would like to know what this really does? Why is this causing these check sum errors? Is there a repercussion of disabling this feature or not? I should also note that we are running on GIG backbone if that matters or not.
Thanks in advance.