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

  • From: Peter J Hill
  • Date: Mon Jan 26 11:54:21 2004 
On Jan 26, 2004, at 2:04 AM, Alexei Roudnev wrote:

1) Cisco ISL is much better than urgly 802.1q - first of all, it was
designed many years before 802.1q. I am not even talking abiout those
idiots, who designed 802.1q as a _spanning tree on the trunk level_, which
made many configurations (which we used with ISL ain 199x years) impossble,
and caused vendors to extend 802.1q.
Is it April 1st? ISL changes the size of packets, does it not? So know you have to deal with MTU issues. What happens when I want the biggest MTU possible? I know it is not much a difference in size, but for some people, size does matter.

I am quite happy with dot1q. My gripe is with poor spanning-tree implementations. I don't want a single spanning-tree for every vlan on a trunk... I like standards, but I am happy with Rapid-PVST. Just my feelings about the issue. I would never deploy ISL unless I had something like a 1900 that did not do dot1q

2) Of course, VLAN does not infer routing. But VLAN routing can be provided
on the switch fabric, effectively bypassing many traditional drawbacks - see
Cisco 6509, for example.
Are you talking about multilayer switching implementations? That is why C came out with dCEF. I costs, but if you want to do serious routing, damn if it ain't fast ;-)

----- Original Message -----
From: "Brian Wallingford" <[email protected]>
To: "Alexei Roudnev" <[email protected]>
Cc: "ken emery" <[email protected]>; <[email protected]>
Sent: Sunday, January 25, 2004 10:17 PM
Subject: Re: Any 1U - 2U Ethernet switches that can handle 4K VLANs?
On Sun, 25 Jan 2004, Alexei Roudnev wrote:

:
:L3 switchiong is just term for idiots - it is ROUTING in old terms. So,
:VLAN's means _routing_.

Um, no, VLAN does not infer routing. 802.1q and even Cisco's ugly
proprietary ISL both operate at layer two.

As to "L3 switching" and the spin involved in such, it's an old,
predictable story, which we all wrote off as marketing drivel at least a
couple years ago...