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Re: [PCN] PCN WG last call for draft-ietf-pcn-architecture-05.txt



Georgios,

sorry for the rude reaction yesterday.

I appreciate the contribution of you and your team to the experiments 
around PCN as I do appreciate all other PCN experiments known to me. 

This holds whether the text of the architecture document remains as 
is or not. 

Regards,

Ruediger 

-----Original Message-----
From: Georgios Karagiannis [mailto:karagian at cs.utwente.nl] 
Sent: Thursday, August 28, 2008 12:45 PM
To: Geib, Rüdiger
Cc: pcn at ietf.org
Subject: RE: [PCN] PCN WG last call for draft-ietf-pcn-architecture-05.txt

Hi Ruediger

As I shown in previous emails, the definition of the HOSE model covers an
wide area 
and its interpretation depends on the context.
Thus the mentioned model can be seen as a HOSE model in the PCN context.

As you could follow the discussion with Steven, this model is 
not out of the PCN WG scope.

Best regards,
Georgios




> -----Original Message-----
> From: Geib, Ruediger [mailto:Ruediger.Geib at t-systems.com] 
> Sent: donderdag 28 augustus 2008 11:44
> To: karagian at cs.utwente.nl
> Cc: pcn at ietf.org
> Subject: RE: [PCN] PCN WG last call for 
> draft-ietf-pcn-architecture-05.txt
> 
> Georgios,
> 
> the hose model on an ingress node requires functionalities 
> treating packets irrespective disregarding the destination 
> address and the hose model applied to an egress node there 
> require functionalities working on all packets disregarding 
> their origin address. 
> 
> I've copied in two sections of draft westberg. The mechanisms 
> mentioned there with regard to the hose model:
> - are obviously not related to the hose model.
> - are out of scope of the PCN WG.
> 
> I think the WG can go on now.
> 
> Regards,
> 
> Ruediger
> 
> 
> 
> Quotes from draft-westberg-pcn-load-control-04
> 
> 3.1.2.2.  PCN-egress-node features
> 
>    [snip]
> 
>    Note that if an edge-to-edge pair aggregated state is not available
>    at the PCN-egress-node, e.g., when the HOSE model is used then the
>    PCN-egress-node cannot determine whether a PCN-egress-node 
> associated
>    with the edge-to-edge pair PCN aggregate operates in Normal state,
>    Admission Control state or Flow Termination state.  
> However, even in
>    this case, when a probe packet arrives at the PCN-egress-node, then
>    this request should be rejected if the probe packet is PCN_marking
>    encoded.  Otherwise, i.e., if the probe packet is not PCN_marking
>    encoded, it should be accepted. 
> 
> 3.2.2.   PCN-egress-node
> 
>    [snip]
> 
>    Note that in the ingress-egress-aggregate model the excess rate and
>    the flows to be terminated are associated with the same 
> edge-to-edge
>    (i.e., ingress-egress) pair PCN aggregate and with the same traffic
>    class, i.e., PHB.  In the HOSE model the excess rate and 
> the flows to
>    be terminated are associated with the same traffic class, 
> i.e., PHB.
>    The PCN-egress-node needs to store for each flow the address, e.g.,
>    IP address and port number, of the PCN-ingress-node from where the
>    particular flow passed before arriving to the 
> PCN-egress-node.  This
>    can be for example done by using information that is carried by the
>    external protocols used in combination with the LC-PCN 
> solution.  For
>    the flows that should be terminated the PCN-egress-node informs the
>    associated PCN-ingress-node to terminate them.  If the PCN domain
>    uses thet ingress-egress-aggregate model and if the PCN-egress-node
>    receives any admission flow request, belonging to a ingress-egress-
>    aggregate state operating in flow termination state then 
> the request
>    must be rejected. 
> 
> -----Original Message-----
> From: pcn-bounces at ietf.org [mailto:pcn-bounces at ietf.org] On 
> Behalf Of Georgios Karagiannis
> Sent: Wednesday, August 27, 2008 12:37 PM
> To: philip.eardley at bt.com; slblake at petri-meat.com
> Cc: pcn at ietf.org
> Subject: Re: [PCN] PCN WG last call for 
> draft-ietf-pcn-architecture-05.txt
> 
> Hi Phil
> 
> HOSE model is defined some 20 years ago, please see e.g the following
> article:
> 
> N. G. Duffield, P. Goyal and A. Greenberg, "A Flexible Model 
> for Resource Management in Virtual Private Networks", in:
> Proc. of ACM SIGCOMM, 1999.
> 
> In the above article I found the following definition:
> 
> "A hose is characterized by the aggregate traffic to and from 
> one endpoint in the VPN to the set of other endpoints in the VPN"
> 
> Thus the definition refers to aggregated traffic to and from 
> one edge to and from all other endpoints.
>  
> 
> In our case we refer only to the aggregated traffic from 
> other endpoints to one endpoint.
> 
> Thus what we use is in line with the definition of the HOSE model.
> 
> Best regards,
> Georgios
> 
> 
> 
> 
> > -----Original Message-----
> > From: philip.eardley at bt.com [mailto:philip.eardley at bt.com]
> > Sent: woensdag 27 augustus 2008 11:31
> > To: karagian at cs.utwente.nl; slblake at petri-meat.com
> > Cc: pcn at ietf.org
> > Subject: RE: [PCN] PCN WG last call for 
> > draft-ietf-pcn-architecture-05.txt
> > 
> > I thought your emails with steve had revealed that your 
> model was the 
> > exact opposite of the well known hose model?
> > 
> > 
> > { -----Original Message-----
> > { From: Georgios Karagiannis 
> [mailto:karagian at cs.utwente.nl] { Sent: 
> > 27 August 2008 09:41 { To: Eardley,PL,Philip,CXR9 R; 
> > slblake at petri-meat.com { Cc: pcn at ietf.org { Subject: RE:
> > [PCN] PCN WG last call for draft-ietf-pcn-architecture-05.txt
> > {
> > { Hi Phil
> > {
> > { What I explained is the well know HOSE bandwidth management model.
> > { During the IETF in Dublin, Hein also shown also some 
> results { that 
> > were obtrained using the HOSE model.
> > {
> > {
> > { Best regards,
> > { Georgios
> > {
> > {
> > { > -----Original Message-----
> > { > From: philip.eardley at bt.com
> > [mailto:philip.eardley at bt.com] { > Sent: woensdag 27 augustus
> > 2008 10:20 { > To: karagian at cs.utwente.nl; 
> slblake at petri-meat.com { > 
> > Cc: pcn at ietf.org { > Subject: RE:
> > [PCN] PCN WG last call for { > draft-ietf-pcn-architecture-05.txt
> > { >
> > { > So the question is about adding to the draft:
> > { > A model where the egress measures marks coming from all the { > 
> > ingresses, and makes admission decision based on that.
> > { >
> > { > Before adding anything about this to the draft, I'd like to { > 
> > understand if this is a genuine practical, understood 
> option { > (if 
> > so, OK), or if it's a theoretical possibility or one not { > well 
> > understood.
> > { > (there are many things in the latter category that aren't { > 
> > mentioned in the draft.) { > { > Questions are why this is 
> > interesting, why is it better than { > the models already 
> well-known, 
> > are there comparative analysis { > /simulations?
> > { >
> > { > I suppose I've got 2 general issues:
> > { > [1] every time something is added, overall the document 
> { becomes 
> > harder to understand, more daunting to read & it { > > looks less
> like the WG has consensus.
> > { > [2] this is an INFO doc. People are free to invent ways of { > 
> > using the standards pieces other than the architecture 
> draft { > says, 
> > and indeed in ways not yet dreamt of.
> > { >
> > { > Phil.
> > { >
> > { > { -----Original Message-----
> > { > { From: pcn-bounces at ietf.org
> > [mailto:pcn-bounces at ietf.org] On { > Behalf Of { Georgios 
> Karagiannis 
> > { Sent: 27 August 2008 08:54 { > { To: 'Steven Blake'
> > { > { Cc: pcn at ietf.org
> > { > { Subject: Re: [PCN] PCN WG last call for { > 
> > draft-ietf-pcn-architecture-05.txt
> > { > {
> > { > { Hi Steven
> > { > {
> > { > { > -----Original Message-----
> > { > { > From: Steven Blake [mailto:slblake at petri-meat.com] {
> > > { > Sent: woensdag 27 augustus 2008 6:18 { > To: Georgios {
> > Karagiannis { > Cc: pcn at ietf.org { > Subject: RE: [PCN] PCN 
> > { > WG 
> > last
> call for { > draft-ietf-pcn-architecture-05.txt
> > { > { >
> > { > { > On Tue, 2008-08-26 at 16:11 +0200, Georgios 
> Karagiannis wrote:
> > { > { >
> > { > { > > Hi Steven
> > { > { > >
> > { > { > >
> > { > { > > Please see in line!
> > { > { > >
> > { > { > >
> > { > { > > > -----Original Message----- { > { > > > From: 
> Steven Blake 
> > [mailto:slblake at petri-meat.com] { { > > > > Sent: dinsdag 
> 26 augustus 
> > 2008 14:46 { > > > To:
> > { > Georgios Karagiannis { > > > Cc: pcn at ietf.org { > > > { >
> > Subject: Re: [PCN] PCN WG last call for { > > > { > 
> > draft-ietf-pcn-architecture-05.txt
> > { > { > > >
> > { > { > > > On Tue, 2008-08-26 at 11:44 +0000, Georgios Karagiannis
> > wrote:
> > { > { > > >
> > { > { > > > > Hi Phil, Hi all
> > { > { > > > >
> > { > { > > > > Here are some  comments on the PCN architecture draft:
> > { > { > > > >
> > { > { > > > > 1) Thank you for clarifying the bullet in 
> Setion { > 3.2 
> > about flow { > > > > termination.
> > { > { > > > >
> > { > { > > > > 2) From what I understand the PCN 
> architecture { > draft 
> > { > > > mentions that PCN { > > > > supports only the { > trunk 
> > (ingress-egress-aggregate) and not the { > > >
> > > HOSE model.
> > { > { > > > > Is the PCN architecture draft excluding solutions { > 
> > that { > support the { > > > > HOSE model? If not, please { > 
> > emphasize in the PCN { > architecture draft {
> > > > > that { > "solutions that are based on other types of 
> > flow { > 
> > > > > > >
> { > aggregation than { > > > > the 
> > ingress-egress-aggregate { > method of flow { > 
> aggregation, are not { 
> > > > > > excluded { > from the PCN WG activities."
> > { > { > > >
> > { > { > > > Actually they are, by our charter.
> > { > { > >
> > { > { > > I have not seen that the PCN charter excludes other { > 
> > types { > of aggregation.
> > { > { >
> > { > { > Well, I checked, and you are correct (mea culpa).
> > { > { Georgios: No problem
> > { > {
> > { > { >
> > { > { > > Please note
> > { > { > > that I am refering to the HOSE model where the 
> traffic { > 
> > sent { > by one or { > > more than one ingresses towards one { > 
> > egress is aggregated at the { > > egress. In this way higgher { > 
> > traffic aggregation can be accomplished { > > than in the { > 
> > situation that the pipe/trunk { >
> > (ingress-egress-aggregate) { > { > > is used, where the 
> traffic sent 
> > by only one ingress in { > aggegated at { > > the egress.
> > { > { >
> > { > { > Typically the "hose" model refers to 
> point-to-multipoint { > { 
> > > traffic flow, not multipoint-to-point.
> > { > { Georgios: Typically yes, but in this case we refer to { 
> > bandwidth allocation { in a multipoint-to-point fashion.
> > { > {
> > { > { >
> > { > { >
> > { > { > Regards,
> > { > { >
> > { > { > // Steve
> > { > { >
> > { > {
> > { > {
> > { > { _______________________________________________
> > { > { PCN mailing list
> > { > { PCN at ietf.org
> > { > { https://www.ietf.org/mailman/listinfo/pcn
> > { >
> > {
> > 
> 
> 
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> 


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