Re: your mail

[Ramakrishna Gummadi <ramki@cs.berkeley.edu>]

On Wed, 18 Jul 2001, Daniel Senie wrote:

> At 03:52 PM 7/18/01, Ramakrishna Gummadi wrote:
> >Hi,
> >
> > >
> > > I know how fair queueing works.  What I'm saying is that if I'm
> > > multihoming via tunnels like this, fair queuing is not what I'm paying
> > > for...I'm paying for QoS beyond that.
> >
> >First of all, the site uses normal links if there are no problems. It only
> >switches to tunnels when there is are failures. I don't think it is fair
> >to say we are "multihoming via tunnels" in all contexts.
>
> So let's make sure everyone is clear on this point. You're saying the only
> reason to multi-home is for failover purposes. As long as the "primary"
> link is up, the "secondary" interface (which is used solely to carry
> tunneled traffic in the event of an outage with the primary) is never used.

No, all I am saying is a normal working link can carry tunneled traffic
in the face of an outage in addition to the normal traffic; thus, if a
site has 11 links (possibly to 11 different providers) that each operate
under 90% utilization in normal conditions, when a provider or link goes
down, the remaining 10 links carry both the spillover (9% each) and the
normal
traffic, so that they now operate at near-full (99%) utilization.

thanks,
ramki