From owner-freebsd-net@FreeBSD.ORG  Fri Mar 26 12:54:55 2004
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Date: Fri, 26 Mar 2004 12:54:54 -0800
From: Luigi Rizzo <rizzo@icir.org>
To: "Marc G. Fournier" <scrappy@hub.org>
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	from scrappy@hub.org on Fri, Mar 26, 2004 at 04:25:55PM -0400
cc: freebsd-net@freebsd.org
Subject: Re: Looking for switch recommendations ...
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On Fri, Mar 26, 2004 at 04:25:55PM -0400, Marc G. Fournier wrote:
> On Fri, 26 Mar 2004, Bakul Shah wrote:
> 
> > For 100Mbps ports, the max packet rate in one direction is 10^8/672 ==
> > 148809 pps (packets per sec) per port.  So for 24 port full duplex ports
> > you get an aggregate maximum throughput of 148809*24*2 = 7738068 =
> > 7.14Mpps (Million pps). For a 48 port switch it is 14.29Mpps.
> 
> so, the closer the Mpps gets to that 7.1Mpps, the better the switch
> overall?  I take it that has to do with the CPU driving the switch itself,

there is no 'cpu driving the switch', forwarding is done
in hardware even in the cheapest units. E.g. see
http://www.realtek.com.tw/products/products1-1.aspx?lineid=2

a switch (Edimax) based on the 8316 costs here 60 euro incl.VAT
and does 16 ports full duplex at full wire speed on all ports.

	cheers
	luigi