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Matcha's avatar
Matcha
Icon for New Contributor rankNew Contributor
5 years ago
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Efficient Way to store and compare MAC addresses

Hello,

I am quite new to using higher level FPGA elements since in college we only used small scale designs with at most 16-bit wide busses and predefined data paths so forgive me if this question is noobish.

I have been given a list of MAC addresses that I need to store and then compare with incoming ethernet frames in a whitelist fashion. I am using the Triple Speed Ethernet IP.

My initial idea was to use a CAM but I have come to understand that modern FPGAs don't have them. I am now thinking to store the addresses in BRAM but now comes the question of how to compare them. Is it possible to have a 48-bit wide comparator or even a 96-bit wide comparator to compare src and dest MACs in a single shot?

Thank you in advance for the help

  • KennyT_altera's avatar
    KennyT_altera
    5 years ago

    Yes, if you want to make comparison. You can make use of the comparator, all the IP is in the IP catalog.


    What I would suggest is you use modelsim to make sure the behavior is the one that you want.


3 Replies

  • KennyT_altera's avatar
    KennyT_altera
    Icon for Super Contributor rankSuper Contributor
    5 years ago

    Yes, if you want to make comparison. You can make use of the comparator, all the IP is in the IP catalog.


    What I would suggest is you use modelsim to make sure the behavior is the one that you want.


    • Matcha's avatar
      Matcha
      Icon for New Contributor rankNew Contributor
      5 years ago

      Hi yes, this helped me out. I able to make a comparator with the bus widths I needed through the IP generator.

  • KennyT_altera's avatar
    KennyT_altera
    Icon for Super Contributor rankSuper Contributor
    5 years ago

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