Incorrect NDIS Filtering of Some Ethernet Multicast Frames

ID: Q216303

The information in this article applies to:

Microsoft Windows NT Server version 4.0

SYMPTOMS

Some Ethernet multicast frames may be incorrectly identified as Ethernet broadcast frames by the filtering logic in Ndis.sys.

Consequently, these multicast frames are not always delivered as expected to NDIS packet drivers and higher layers of the network stack.

CAUSE

Ethernet multicast frames are distinguished from directed packets by having the Individual/Group (I/G) bit of the destination address set to 1 (Group).

The Ethernet broadcast address is defined to be 0xFFFFFFFFFFFF, which is a special case of Ethernet multicast address.

Frames with an Ethernet multicast destination address whose first byte was 0xFF were being incorrectly identified and treated as broadcast frames.

WORKAROUND

To work around this problem, choose an Ethernet multicast addressing scheme that does not include Ethernet multicast addresses whose first byte is 0xFF.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:

http://www.microsoft.com/Windows/ServicePacks/

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack

For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

NOTE: If this product was already installed on your computer when you purchased it from the Original Equipment Manufacturer (OEM) and you need this fix, please call the Pay Per Incident number listed on the above Web site. If you contact Microsoft to obtain this fix, a fee may be charged. This fee is refundable if it is determined that you only require the fix you requested. However, this fee is non-refundable if you request additional technical support, if your no-charge technical support period has expired, or if you are not eligible for standard no-charge technical support.

For more information about eligibility for no-charge technical support, see the following article in the Microsoft Knowledge Base:

Q154871 Determining If You Are Eligible for No-Charge Technical Support

STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0. This problem was first corrected in Windows NT version 4.0 Service Pack 5.

Additional query words: 4.00

Keywords : kbbug4.00 kbfix4.00 nt4sp5fix
Version : winnt:4.0
Platform : winnt
Issue type : kbbug