Hi Sabine,
Thanks for providing the comments.
My response for some of the comments , even though Young has already
clarified most of them.
++ Section 3.1 ALTO Query from Application Stratum to Network Stratum
Names used in the list of requested information may be misleading:
- A 'Cost Type' see base protocol (§5.1.1) is expected to indicate an
attribute that has a value such as number, boolean, string... and is is
rather "semantic". 'summary' and 'graph' are cost attributes of different
nature.
----[sreekanth]: We will be extending the Cost-Type and would like to keep
the Cost-Mode as Summary and Gragh.
++ Section 3.4 Information Model of ALTO Response ...
- object CsoInfoResourceEndpointCostMap has the same structure than
InfoResourceEndpointCostMap of base protocol - what in the list of §3.2 does
object 'DstCostsConstraints' refer to?
- this object seem to be encoded like a set of JSONNumbers that are the
values of resp. hopcount, latency and packet loss. So I guess, they should
be arranged in an array.
----[sreekanth]: Alto response:
object {
JSONNumber hopcount;
JSONNumber latency;
JSONNumber pktloss;
} DstCostsConstraints;
object EndpointDstCosts {
DstCostsConstraints[TypedEndpointAddr]; ...
};
object {
EndpointDstCosts [TypedEndpointAddr]<0..*>;
...
} EndpointCostMapData;
object {
CostMode cost-mode;
CostType cost-type;
EndpointCostMapData map;
} CsoInfoResourceEndpointCostMap;
For each Source Endpoint, a EndpointDstCosts object denotes the associated
"cost + constraints" to each
Destination Endpoint specified in the input parameters; the name for each
member in the object is the TypedEndpointAddr string identifying the
corresponding Destination Endpoint. This can be viewed as a two dimensional
array which holds cost + constraints value.
We extended the EndpointDstCosts by adding constraints value and hence
cannot reuse the EndpointDstCosts (which is wrong in the current
draft)object defined by base. The same is the case for
InfoResourceEndpointCostMap object of the base.
- why is this set of cost types already set at this level of specification?
----[sreekanth]: Could you please clarify this point ?
Regards,
Sreekanth
-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of
Sabine Randriamasy
Sent: Tuesday, July 31, 2012 10:51 PM
To: Leeyoung
Cc: [email protected]
Subject: Re: [alto] [altoext] FW: New Version Notification for
draft-lee-alto-app-net-info-exchange-00.txt
Hi Young,
Thanks for your answers. Please see inline for further comments.
I have put the "alto" list in Cc rather than "altoext" which will be closed.
Best regards
Sabine
Leeyoung a écrit :
> Hi Sabine,
>
> Thanks for providing your comments to our drafts. Please see in-line for
my response.
>
> Best Regards,
> Young
>
> -----Original Message-----
> From: Sabine Randriamasy [mailto:[email protected]]
> Sent: Monday, July 30, 2012 12:14 PM
> To: Leeyoung
> Cc: [email protected]
> Subject: Re: [altoext] FW: New Version Notification for
draft-lee-alto-app-net-info-exchange-00.txt
>
> Hi Young,
>
> I have read your draft and have a couple of comments and questions.
>
> In Section 2 Problem statement, I agree with the need to reduce the
> amount of conveyed ALTO information through topology filtering and
> constraint-based response filtering. The ALTO base protocol specifies
> these features for the Cost Map, Filtered cost map and Endpoint cost
> services. I also agree with the necessity to provide several types of
> cost information which stresses the necessity of extended filtering
> mechanisms. In the Constraints filtering extensions of Section 3, I
> didnt' really get how information confidentiality is preserved and the
> proposed specification raised the questions detailed below.
>
> YOUNG>> Information confidentiality is a big issue which the current draft
has not addressed yet. The current draft was written in the "controlled" or
"partially controlled" environments which means there is a trusted
relationship amongst the entities involving the exchanges of resource data.
> In generic framework where there may be no such trusted relationship
amongst the entities, we need to address such issue down the road.
>
Ok. Indeed, ALTO environment control is introduced in the Introduction.
I was mislead by seing "Such information may be considered sensitive to
the network provider just as..." just before "Section 3 provides ALTO
information model and protocol extensions to support... "
> I also agree that detailing end to end path costs at the link level at
> some places can be beneficial, especially for local bottlenecks
> sometimes with fast changing cost values. Figure 2 shows an example with
> Link capacity costs but section 2 uses them rather as capacity, where I
> figure the higher the better. Without a hint on how path costs are
> calculated it is hard to follow the rationale on the DC choice by ER1.
> See also the questions detailed below.
>
> YOUNG>> We actually enhanced this mechanism in section 6 of
draft-bernstein-alto-large-bandwidth-cases-02.txt
> where we include path vector along with link b/w. Path vector indicates
shared link information from which
> The bottle neck link can be identified.
>
> For instance, consider the following example from the draft.
>
>
> +----+ L0 Wt=10,BW=50 +----+
> | N0 |-----------------------------------------| N3 |
> +----+ `. +----+
> | `. L4 Wt=7 |
> | `-. BW=40 |
> | `. +----+ |
> | `.| N4 | |
> | L1 .' +----+ |
> | Wt=10 / L2 |
> | BW=45 / Wt=12 |
> | /L5 Wt=10 BW=30 |
> | .' BW=45 |
> | / |
> | / |
> +----+ .' L3 Wt=15 BW=42 +----+
> | N1 |.........................................| N2 |
> +----+ +----+
>
> Now suppose the network of Figure 1 is a TDM network controlled by
> GMPLS. Once again N0 representing a large data center and nodes N2
> and N3 as potential clients. However in this case the network provider
> offers an additional path, P3, for getting from N0-N2.
>
> Path Src-Dest Path Vector Path Cost
>
> P1 N0-N2 {L0, L2} 22
> P2 N0-N3 {L0} 10
> P3 N0-N2 {L1,L3} 25
> ----------------------------------
> Link Bandwidth
> L0 50
> L1 45
> L2 30
> L3 42
>
> So the draft now propose that the network can provide abstract path
> list along with link bottlenecks. We also provide how this mechanism
> works for IP and other types of networks.
>
I'm fine with the rationale in
draft-bernstein-alto-large-bandwidth-cases-02.txt. It's just that in
draft-lee-alto-app-net-info-exchange-00.txt I missed the relation
between the "LinkCapacity Cost" & ALTO Cost Map in Figure 2 and also the
explanatory text text. Maybe a little clarifying edition can help.
> I will provide the responses to your detail questions later.
> Thanks.
>
> Young
>
>
>
>
>
> Thanks,
> Sabine
>
> ------------------------- Detailed questions -----------------------------
>
> ++ Section 3.1 ALTO Query from Application Stratum to Network Stratum
> Names used in the list of requested information may be misleading:
> - A 'Cost Type' see base protocol (§5.1.1) is expected to indicate an
> attribute that has a value such as number, boolean, string... and is is
> rather "semantic". 'summary' and 'graph' are cost attributes of
> different nature.
> - 'Constraints' such as 'min/max metric' look like objectives rather
> than expressions such as 'lt. value' as specified in the base protocol
> (§ 6.8.2.2.3)
> - what kind of information is member 'Parameters' is supposed to carry
> and for what use?
> - Some members listed here do not appear in the ALTO Query Information
> Model of §3.3: 'parameters' 'objective-function'. Neither do they appear
> in the example of §3.5
>
>
> ++ Section 3.2 ALTO response from Network ....
> - The list of S-D pairs should carry the Cost Type *values* as the
> supported Cost Types are expected to be listed and checked in the IRD.
> - 'Constraint values': need to be clarified: is it the actual cost
> value? then the draft should specifiy that the constraits relate to Cost
> Types (as defined in §5.1.1).
> - how is the 'Administration Domain ID' of a S-D pair reported and why
> is it needed?
>
>
> ++ Section 3.3 Information Model of ALTO Query ...
> Looking at the specification here, it is hard to figure out what is
> really extended here w.r.t. the Endpoint Cost Service query input
> specified in the base protocol.
> - A new media type "CsoReqEndpointCostMap" and differs from
> "ReqEndpointCostMap" of the base protocol in that the set in member
> 'contraints' is encoded/interpreted differently, according to example in
> §3.5. Then a different member name than 'contraints' should be used.
> - As for member 'endpoints': unless you need to specify only 1 src EP,
> what is the need to define a new object "EndpointFilterExt" instead of
> keeping the "EndpointFilter"?
>
>
> ++ Section 3.4 Information Model of ALTO Response ...
> - object CsoInfoResourceEndpointCostMap has the same structure than
> InfoResourceEndpointCostMap of base protocol
> - what in the list of §3.2 does object 'DstCostsConstraints' refer to?
> - this object seem to be encoded like a set of JSONNumbers that are the
> values of resp. hopcount, latency and packet loss. So I guess, they
> should be arranged in an array.
> - why is this set of cost types already set at this level of
> specification?
>
>
> ++ Section 3.5 ALTO protocol extension...
> I agree with the idea of providing several Cost Type values at a time
> but the encoding could be lighter. The draft "Multi-Cost ALTO" proposes
> one example.
> There is a real need that this section be harmonized with the previous
> specification sections, as the encoding provided in the examples are
> misleading.
>
>
> ++ Section 4.1 Representing....
> - this section is rather about representing links and their attributes,
> so could be named accordingly
> - the graph specification is curretnly a list of links, do you intend to
> extend so that one can infer its structure?
> - is there a reason preventing member 'r-cap' to be specified as
> JSONNumber capacity?
> - what is the usage of wt at this level of a spec ? (could also be
> 'JSONNumber weight')
>
> Leeyoung a écrit :
>
>> Hi All,
>>
>> We have just published ALTO extension to support application and network
resource information exchange for high bandwidth applications.
>> This is part of the i2aex initiative.
>>
>> Thanks in advance for your comment and discussion.
>>
>> Young
>>
>> -----Original Message-----
>> From: [email protected] [mailto:[email protected]]
>> Sent: Monday, July 09, 2012 11:06 AM
>> To: Leeyoung
>> Cc: [email protected]; Sreekanth madhavan; [email protected];
Dhruv Dhody
>> Subject: New Version Notification for
draft-lee-alto-app-net-info-exchange-00.txt
>>
>>
>> A new version of I-D, draft-lee-alto-app-net-info-exchange-00.txt
>> has been successfully submitted by Young Lee and posted to the
>> IETF repository.
>>
>> Filename: draft-lee-alto-app-net-info-exchange
>> Revision: 00
>> Title: ALTO Extensions to Support Application and Network
Resource Information Exchange for High Bandwidth Applications
>> Creation date: 2012-07-09
>> WG ID: Individual Submission
>> Number of pages: 14
>> URL:
http://www.ietf.org/internet-drafts/draft-lee-alto-app-net-info-exchange-00.
txt
>> Status:
http://datatracker.ietf.org/doc/draft-lee-alto-app-net-info-exchange
>> Htmlized:
http://tools.ietf.org/html/draft-lee-alto-app-net-info-exchange-00
>>
>>
>> Abstract:
>> This draft proposes ALTO information model and protocol extensions to
>> support application and network resource information exchange for high
>> bandwidth applications in partially controlled and controlled
>> environments as part of the infrastructure to application information
>> exposure (i2aex) initiative.
>>
>>
>>
>>
>>
>>
>> The IETF Secretariat
>> _______________________________________________
>> altoext mailing list
>> [email protected]
>> https://www.ietf.org/mailman/listinfo/altoext
>>
>>
>
>
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