[Pc_Support] Re: ABS 8-Port, 5-Port GbE Switch -- VSC7388, VSC7385 (Blog article)

[Derek Konigsberg]

>> On my x86 machines, my GigE fiber NICs are Netgear GA620's.
>
> I several of those to Intel 510 and Bay 450 switch stacks in the late
> '90s.  They have 512KiB SRAM buffer, although that was rather small
> for the time (1-2MiB SRAM was typical).  No 802.3x support IIRC.

Yes, they *do* have 802.3x support.  At least according to what my Intel 
470F switch tells me, and what's written in this PDF of the install guide:
http://www.netgearinc.co.jp/support/manual/ga620t/installguide.pdf
(page 2, upper-right corner)

> Today I wouldn't put anything but a wire-speed layer-3 switch,
> 20+Mbps fabric and use Jumbo Frames for anything GbE or that is
> possible of supporting it.  Running with old managed layer-2 switches
> typically offer little benefit over today's commodity switch ASICs.

First of all, why would you pay for a layer-3 switch if you have 
absolutely no intention/desire/need to do routing inside that switch?

Second of all, while Jumbo frames do many sense if you're trying to 
maximize GigE performance, normal-size frames also make sense for 
interoperability.  One setup I could forsee would involve a jumbo-frame 
VLAN for back-end high speed communications, and a normal-frame VLAN for 
communications with 10/100Mbps end hosts.

With my setup, the only reason I'm really not yet doing jumbo frames is 
that I'm still mostly 100Mbps.  Also, I'm using some of my "in the server" 
GigE cards more for their VLAN capabilites than raw performance at the moment.
(based on what hardware I had at the time when I set things up)

---------------------------
Derek Konigsberg
octo at logicprobe.org
http://hecgeek.blogspot.com
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