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Re: Re (2): Linux hub



Celejar put forth on 9/7/2010 6:58 PM:

> I suppose, but since the vast majority of applications of cheap
> switches don't require this capability, wouldn't it be cheaper to leave
> it out, and only include it as an extra feature for those who need it?
> 
> I don't actually know what it costs them to include the RAM for the MAC
> table, though; perhaps it's negligible, so they just always throw it in.

Considering the cost of the entire switch IC in a $10 USD 8 port switch
(which includes an external AC/DC transformer and a 3 foot ethernet
patch cable for the price) is less than $1 in 10k unit quantities,  the
cost of say 64KB RAM on that switch chip is going to be in the 10 cent
range or less.

The reason many/most cheap 4/8/16 port switches have an 8192 entry MAC
table is because they're all likely using the same switch chip from a
single vendor, and this chip was designed with an 8192 entry MAC table.
 The chip is cheap, reliable, and available in large quantities, so
everyone uses it.

-- 
Stan


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