u wrote
The selection of the root
> bridge and which interfaces are blocking might not be optimized for all
the
> applications and devices in the large, switched network.
>
> With per-VLAN spanning tree, each VLAN becomes a single spanning tree with
> its own root bridge and own set of blocked ports. This way you can
optimize
> traffic flow and reduce the amount of work to converge to a spanning tree.
my question
does the root bridge helps in data path flow...? i dont think so..
also if u can define the data flow in the network
with and without vlan
regards
have a good day!!
fa
----- Original Message -----
From: "Picciani Francesco Saverio"
To:
Sent: Tuesday, August 07, 2001 5:09 PM
Subject: R: vtp, spanning tree [7:14961]
> I thing that the main benefit of having per-VLAN spanning tree is that a
> problem on a VLAN does not impact the other VLANs also if they lay on the
> same ISL trunk.
>
> -----Messaggio originale-----
> Da: Priscilla Oppenheimer [mailto:[EMAIL PROTECTED]]
> Inviato: lunedl 6 agosto 2001 20.05
> A: [EMAIL PROTECTED]
> Oggetto: Re: vtp, spanning tree [7:14961]
>
>
> At 02:13 PM 8/5/01, Cisco Troubleshooter wrote:
> >can any body tell,
> >
> >why we need spanning tree protocol per vlan
>
> If you have a large, switched network, all the switches are in the same
> spanning tree. Converging the spanning tree can take a long time. In
> addition, traffic flow may not be optimized. The selection of the root
> bridge and which interfaces are blocking might not be optimized for all
the
> applications and devices in the large, switched network.
>
> With per-VLAN spanning tree, each VLAN becomes a single spanning tree with
> its own root bridge and own set of blocked ports. This way you can
optimize
> traffic flow and reduce the amount of work to converge to a spanning tree.
> It's somewhat analogous to dividing a routed network into areas or
> autonomous systems.
>
> Also, at least with Catalyst 1900 switches, if you allow all VLANs to
> travel across both trunks, you will have a loop. If you don't configure
> per-VLAN spanning tree, you will have a broken network. You would think
> spanning tree would just work around this problem, but it doesn't seem to
> when VLANs are configured.
>
>
> >and vtp why it is needed what purpose it serves
>
> VTP is a management protocol that allows switches to share information
> about VLAN names and IDs. It reduces configuration because you can
> configure VLAN names and IDs on just one or two server switches. The rest
> of the switches act as clients and pick up the info when they boot.
>
> By default, the switches do not keep track of which switches have which
> VLANs configured, however. I disagree with the other responder who said
VTP
> reduces bandwidth usage on links and switches. It's VTP pruning that does
> that.
>
> If you configure VTP pruning, then an added VTP message gets sent. The
> added message includes VLAN membership information. With VTP pruning, the
> switches become a bit smarter and do not forward traffic for a VLAN across
> a link or to a switch that has no ports in that VLAN. This must be
> configured. Without pruning, VTP just shares info about VLAN names and
IDs.
>
> Priscilla
>
>
> >thnx in advance
> >
> >jd
> >
> >__________________________________________________
> >Do You Yahoo!?
> >Make international calls for as low as $.04/minute with Yahoo! Messenger
> >http://phonecard.yahoo.com/
> ________________________
>
> Priscilla Oppenheimer
> http://www.priscilla.com
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=15110&t=14961
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