Re: [802.21] Meeting minutes of today's ad-hoc teleconference
Hi Eunah,
On Wed, Aug 24, 2005 at 11:07:40AM +0900, Eunah Kim wrote:
> Hi Yoshihiro,
>
> Thanks for your taking minutes.
> I'd like to correct a part of the minutes which is about
> what I said in the telecon last night.
>
> As for Ia interface,
> I meant that "it would be (n:n), not end-to-end
> as multiple UEs also can communicates with one NISP.
Thanks for the correction.
>
> But, if Ia is an interface between one UE and the network like Subir said,
> (1:n) will be fine.
Yes, I think so.
>
> By the way,
> when will it be the case of (1:n)?
An UE attached with only one NISP can communicate with multiple IS
Functions within the NISP, if the information databases are
distributed in the NISP. An example is that XML/RDF databases can be
distributed similar to DNS.
>
> My understanding is that one UE can communicate with only one NISP at a moment.
> The reason for having (1:n) would be the case that the UE moves so needs to connect
> with a different NISP from the previous one. Am I right?
Yes, the multi-NISP case is one obvious reason. There can be other
reason as I described above. BTW, I think the current reference model
does not seem to preclude the case in which one UE communicates with
multiple NISPs at a moment, as the model just defines interfaces. We
can discuss this level of details in the process of identifying actual
requirements.
Hope this helps,
Yoshihiro Ohba
>
> Regards,
>
> Eunah
>
>
> ----- Original Message -----
> From: "Yoshihiro Ohba" <yohba@TARI.TOSHIBA.COM>
> To: <STDS-802-21@listserv.ieee.org>
> Sent: Wednesday, August 24, 2005 1:40 AM
> Subject: [802.21] Meeting minutes of today's ad-hoc teleconference
>
>
> >
> > Meeting minutes of ad-hoc teleconference about
> > IS reference model and use-cases
> >
> > August 23rd, 9am-11:10am EST
> >
> > Discussed document: 21-05-0336-00-0000-IS_Reference_Model_and_Use_Cases.ppt
> > (posted on the reflector.)
> >
> > Participants
> > ------------
> >
> > Subir Das
> > Farooq Bari
> > Vivek Gupta
> > Ulisis Olvera-Hernandez
> > Qiaobing Xie
> > Ajoy Singh
> > Ajay Rajkumar
> > Peretz Feder
> > Soohong Daniel
> > Stefano Faccin
> > Cheng Hong
> > Eunah Kim
> > Kalyan Koora
> > Yoshihiro Ohba (minutes taker)
> > Mattias Pettersson
> > Prasad Govindarajan
> > Srinivas Sreemanthula
> > Reijo Salminen
> > Eleanor Hepworth
> >
> > What was agreed
> > ---------------
> >
> > - Ia: joint-scope of IEEE/IETF.
> >
> > - Ia': joint-scope of IEEE/IETF if it is different from Ia. If Ia'
> > and Ia are the same, just replace Ia' with Ia.
> >
> > - Ix: out of the scope of IEEE.
> >
> >
> > Action item
> > -----------
> >
> > - Upload the current slide.
> > - Update the slides based on the agreement.
> > - Before the next teleconf, create a strawman of actual IETF requirements
> >
> > Detailed discussion
> > -------------------
> >
> > [Subir] First slide is to capture rererence model. First figure
> > describes single hop model. 2nd figure multi-hop model. Single-hop
> > basically means IP link (in terms of IETF req.). Network IS provider
> > is where we can get the information. In Information Database,
> > information is stored. Interface Ix is not 802.21 scope. This is Ix
> > is for capturing the scenarios. Ia' could be Ia, we don't see much
> > differences.
> >
> > [Ulisis] Why Ia' could be Ia could be different?
> > [Subir] Ia' some information may be added by 802.21 ISF in the network.
> > [Ulisis] Are we going to define an intermediate function?
> > [Ulisis] Each NISP tends to have its own information database. How it
> > is covered.
> > [Subir] It is captured in the first case.
> >
> > [Ajoy] A protocol is defined between MN and AR?
> > [Subir] Placement of protoocl entity can be separately discussed.
> > [Subir] Two NISP communicating each other is covered in the reference model
> > [Ajay] This discussion is only for IS. Two IS functions in the
> > network talking to each other is separate discussion.
> >
> > [Subir] If we define interfaces, why can't we use the same interface for
> > communications between IS Functions in network.
> >
> > [Farooq] What is the diffrence in requirements? If two diferent autonomous systems
> > communicate, then the interface is Ia'.
> >
> > [Ajoy] communications between IS Functions in network can be a
> > peer-to-peer model. Ia is client-server model.
> >
> > [Subir] It is our job to put requirements if Ia' has some difference from Ia.
> >
> > [Ajay] Definition of IEs can be done in parallel to the discussion of
> > reference model and use-cases discussions.
> >
> > [Ulisis] Upper-layer proxy is talking to information database via Ix?
> >
> > [Subir] Yes, but the two end of Ix are not an IS function. Ix can be
> > anything. We can mention it it is outsope.
> >
> > [Qiaobing]: There is another model we may need to capture. For
> > example, IS function in UE is communicating with a proxy that is also
> > inside the UE and then it is using the Ix interface to communicate
> > with the information database.
> >
> > [Subir] Yes, that is a valid model but it will out of scope since Ix
> > is out of scope. But we will capture this model and Xiaobing will
> > send the model diagram.
> >
> > [Eunah] What is the meaning of "(1:n)"?
> >
> > [Subir] It means UE can communicate with multiple MIHFs.
> >
> > [Yuna] Ia could be end-to-end.
> >
> > [Farooq] Mapping is UE to the network.
> >
> > [Ajoy] What is end-to-end? How UE can choose one MIHF.
> >
> > [Ajay] Ia is possible IS function and information database are
> > combined.
> >
> > [Farooq] Ia and Ia' may have different security characteristics.
> >
> > [Kalyan] Can two UEs communiating each other via Ia? Another UE may
> > have obtained the information from the network.
> >
> > [Subir] It might be a multi-hop model. It could be described in Case
> > 1 or 2 as a note.
> >
> > [Kalyan] The intermediate network may be an ad hoc network. The term
> > NISP in that case should be ISP
> >
> > [Farooq] Is it not then the network from an UE?
> >
> > [Ajay] We are going to some philosophical discussion here.
> >
> > [Ajoy] How many interfaces we are discussing in 802.21.
> >
> > [Subir] Ia and Ia'.
> >
> > [] Not all elements should have information database.
> >
> > [Farooq] It should be captured in the spec.
> >
> > [] All IS Function in network has an access to the information
> > database. Then why Ia' is needed?
> >
> > [Subir] Multihop model is trying cover AAA-proxy like scnearios.
> >
> > [Ajay] I agree with Subir.
> >
> > [Ulisis] From the UE's perspective, Ia' or Ix does not matter.
> >
> > [Subir] True. From the UE perspective it is a single model, similar
> > to AAA model.
> >
> > Slide 5:
> >
> > [Peretz] Is this scoping discussed in Paris IETF meeting?
> >
> > [Subir] Yes. If there is a scenario that is missing, please bring it.
> >
> > [Kalyan] Ix is now IETF scope? If there is Ix and it is IETF scope,
> > why do we want to show this interface?
> >
> > [Subir] We are not saying that Ix is IETF scope, we are questioning
> > about this.
> >
> > [Kalyan] Is Ix implementation specific?
> >
> > [Ajay] Yes.
> >
> > [Farooq] But we need to say something about Ix to explain the scenarios.
> >
> > [Ajoy] What is the meaning of joint-scope?
> >
> > [Subir] IEEE relies the interface to be standardized in the IETF and
> > requirements are sent to IETF.
> >
> > [Peretz] Are you saying that communication betweeen IS functions
> > between different NISPs are in the scope of 802.21?
> >
> > [Subir] Yes.
> >
> > [Ajay] Case 1 is ientifying multi-hop case. In the slide we may need to
> > explicilty mention about this.
> >
> > [Subir] We will separate Case 1 into multiple cases. One case with
> > only one Ia and the other with two Ia-s. And some other.
> >
> > [Ajoy] Ia' should be in scope. Ia could be used instead of Ia' when
> > one NISP is acting as an independent client for the other NISP (Ia''?)
> >
> > [Farooq] What Ia'' is diffrent from proxy?
> >
> > [Subir] We need to identity in various scanrios raised during this
> > discussion. the interface is Ia, Ia' or some other. (proxy, relay or
> > server)
> >
> > [Ohba] UE-to-UE communication in Case 1 might have an issue about MIH
> > discoverying. There will be a big problem if every UEs are trying to
> > anser discovery query.
> >
> > [Subir] Issues should be discussed when trying to create another use
> > cases for UE-to-UE communication information service and we can try to
> > describe requirements about it.
> >
> > [Kalyan] Broadcast-based information service is another use case.
> >
> > [Subir] Ia' is in scope only when it is for proxy and server.
> > If server to server then it is Ia''
> >
> > [Farooq] Ia' or Ia'' is just a client-server interface.
> >
> > [Vivek] That is mostly out of scope of 802.21?
> >
> > [Subir] If we don't see different Ia and Ia', let's just rename Ia' to Ia.
> >
> > [] Why server-to-server communication is out of scope?
> >
> > [Subir] To make it in scope valid scenarios is needed.
> >
> > [] Can Ix go across NISPs?
> >
> > [Ajay] No. If every NISP has its own information database, why Case
> > 2c and Case 3 are needed? It is unreastic to consider a NISP that
> > does not have its information database.
> >
> > [Subir] If we are considering models where NISP always has information
> > database, then Case 2c and Case 3 are not needed.
> >
> > [Ajay] Once agreed, the contents of the slides can be included in the
> > spec during the september meeting.
> >
> > [Vivek] Before the next teleconf, we really need to create a strawman
> > of actual requirements.
> >
> > [Subir] I agree.
>
>