Any 1U - 2U Ethernet switches that can handle 4K VLANs?

haesu at towardex.com haesu at towardex.com
Tue Jan 27 14:19:35 UTC 2004


	welcome to 2004. ISL is a thing of the past. let us move on.
	./end_flamebait.sh

-J (who realized Cisco no longer supports ISL on 2950 and some other newer box)

On Mon, Jan 26, 2004 at 11:09:07PM -0800, Alexei Roudnev wrote:
> 
> So what?  Is is a sugnificant drawback? I do not think so. Both ISL and
> 802.1q require special interface cards (with extended frame size), and I do
> not see any reason, why 26 bytes vs 4 bytes makes big difference. /May be,
> the only pro for 802.1q tagging is it's possible  implementation on the old
> interface cards, which did not allowed extra 30 bytes but allowed extra 4
> bytes/.
> 
> I am no saying that ISL is better tha 802.1q, but 802.1q is not much better
> than ISL, and (in some cases) is even worst.
> 
> 
> ----- Original Message ----- 
> From: <sthaug at nethelp.no>
> To: <alex at relcom.net>
> Cc: <nanog at merit.edu>
> Sent: Monday, January 26, 2004 9:10 AM
> Subject: Re: Any 1U - 2U Ethernet switches that can handle 4K VLANs?
> 
> 
> > > ISL _DOES NOT CHANGE_ packet size.
> >
> > An 802.1q tag adds 4 bytes to the Ethernet frame.
> >
> > ISL encapsulation adds 30 bytes to the Ethernet frame.
> >
> > Steinar Haug, Nethelp consulting, sthaug at nethelp.no

-- 
James Jun (formerly Haesu)
TowardEX Technologies, Inc.
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