[c-nsp] gigabit ethernet ring for metro ethernet deployment

[Rubens Kuhl Jr.]

On 1/5/07, Gert Doering <gert at greenie.muc.de> wrote:
> Hi,
>
> On Thu, Jan 04, 2007 at 09:04:01AM -0800, Voll, Scott wrote:
> > Spanning tree will allow for the shortest path and if something goes
> > down you are redirected to the other side of the ring.
>
> Actually it will allow for the "shortest path to the root bridge".
>
> Depending on where your packets are coming from and going to, it may
> very well be "once around all of the ring" (because the direct link
> happens to be STP-blocked).

PVST or MISTP could be used to tune this behaviour, I think. With PVST
the root of each customer VLAN could be one of the nodes that servers
that customer, with MISTP each node could be root for one instance and
a customer would be served by a VLAN that belongs to the instance of
one of its nodes.


Rubens