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Cut-Through Switch

Unanswered Question
Jun 21st, 2006
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HI All

For cut-through switch i knew that The switch begins by pulling the frame header into its network interface card buffer. As soon as the destination MAC address is known (usually within the first 13 bytes), the switch forwards the frame out the correct port without running CRC.

So is switch in this mode reads rest of the frame portion or not..? (for example sorce address and all).

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Overall Rating: 5 (1 ratings)
leonvd79 Wed, 06/21/2006 - 06:27
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Cut-Trough switches (seldomly used these days) forwards the frame after the first 48 bits (6 bytes). It reads only the destination address and forwards the frame to the output queue.

Although this switching method is documented well, it doest not say how it learns the source addresses that make up the mac address table used for switching decissions. Perhaps someone can comment on that ;-)



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dhavaltandel Wed, 06/21/2006 - 07:27
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HI Leon,

Thanks for the reply,

But I am stuck with this point only that in cut-through mode how switch learn the MAC TABLE.


glen.grant Wed, 06/21/2006 - 07:08
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The ones I ever knew that were cuthru were the old 1924's . Almost all are store and forward now.

devang_etcom Wed, 06/21/2006 - 07:50
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dont mix learning and forwarding procedure ...switch forwarding method is what ever but you have to learn first of all your MAC address...then switch can forward data other wise it will brodacst and learn the mac address of destination...

think about ARP issue you will autometically get your answer...

hope this will help you

reat this post if it helps




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