Eric,
I am not sure if I am just slow here, but I am still not sure what
your answer is.
Do you mean:
A.) No exchange of any information regarding resources is required
B.) Simple reservations and advertisements of resources are allowed,
however, detailed properties of the resources advertised are
negotiated off line.
C.) Full QoS negotiation.
As stated before I believe in B.) . As to the metric of the resources
I would go as far as to say it could be a simple integer. The
meaning of the integer would be defined off line by an SLA.
Also as stated before. The reason for my support of B.) is not that
I want to ensure QoS. The reason is that as of today many CDNs make
reservations for their customers. If my demand changes I have to change
this reservation. This can be either done by a phone call or
by a protocol. In our current case the contract specifies exactly
how this capacity changes are performed.
Oliver
p.s. I completely agree with your assessment of disk capacity as
a metric.
Eric Dean writes:
>
> I believe that capacity management is a function of the CDN provider. If
> a CDN peer consistently is unable to deliver content with sufficient QoS
> then you stop peering with them...or with that portion of the CDN.
>
> QoS mechanisms have been hammered out within the IETF and rarely
> implemented except for some internal traffic engineering. I have never
> seen a bilat (contract or protocol) that has QoS properties.
>
> Exchanging capabilities and exchanging capacity are two completely
> different considerations. It will also make for extremely chatty
> protocols because content will continuously shift.
>
> In addition, disk capacity is rarely a determining factor. I/O, CPU,
> memory are much more of a determining factor and are micro-dynamic.
>
> On Wed, 10 Jan 2001, Oliver Spatscheck wrote:
>
> >
> >
> >
> > Eric Dean writes:
> > >
> > > I also concur that QoS is an offline process...if even quantifed at all.
> > >
> >
> >
> > Eric,
> >
> > please clarify for me. Do you mean with QoS something as simple
> > as space or bandwidth reservation or do you mean something as complicated
> > as the detailed properties reserved bandwidth has to adhere to?
> >
> > I am in complete agreement with you that the "properties of reserved
> > bandwidth" should be negotiated off line. However, the availability
> > and reservation should be an online process.
> >
> > Oliver
> >
>
> Eric Dean
> President, Crystal Ball Inc.
> W 703-322-8000
> F 703-322-8010
> M 703-597-6921
>
>