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multicast hash table, which CRC is used?

spam3
Associate II
Posted on November 17, 2009 at 14:24

multicast hash table, which CRC is used?

1 REPLY 1
spam3
Associate II
Posted on May 17, 2011 at 13:30

Hi everybody,

I'm making an small sensor thing on ethernet, it's using multicast UDP packets for communication. The ethernet chip has a hash table filter for multicast packets. So far so good, but I don't see which CRC algorithm is used for hashing MAC addresses. This is what the manual says:

''For hash filtering, the MAC uses the 6 upper CRC bits of the received destination address to index the content of the Hash table. A value of 000000 selects bit 0 in the selected register, and a value of 111111 selects bit 63 in the Hash Table register. If the corresponding bit (indicated by the 6-bit CRC) is set to 1, the unicast frame is said to have passed the Hash filter; otherwise, the frame has failed the Hash filter.''

Are there implementation example around?