RE: [802.21] AW: [802.21] Comments on Ref. Model
Hi Andrea,
At this point I don't think we have rejected or accepted any proposal. My original e-mail was intended as a means of comparison between the figure in ref (1) and the figure that we provided in ref (3) of this discussion primarily because I found these two models to be quite similar.
We suggested this reference model as it was the basis of our presentation to external standard organization; in particular 3GPP and 3GPP2.
We are open to suggestions regarding generality, however we have identified three main link layer technology groups (802, 3GPP and 3GPP2) and they have different requirements. We need to reflect this in our reference model.
Kind regards,
Ulises
-----Original Message-----
From: Andrea Francini [mailto:francini@LUCENT.COM]
Sent: Tuesday, November 15, 2005 11:44 AM
To: STDS-802-21@LISTSERV.IEEE.ORG
Subject: Re: [802.21] AW: [802.21] Comments on Ref. Model
Hello Kalyan and Ulises:
I have a general comment regarding the purpose of the "General MIH Reference
Model" figure (Figure 3 in Section 5.5 of the current draft):
Since Figure 3 describes the "General" model, I believe that any reference to
specific access technologies should be removed from it. Otherwise the figure
turns out to be a compact summary of the technology-specific figures that follow
in Sections 5.5.1 through 5.5.5., instead of working as a template for their
generation. In a technology-specific subsection, it would be ideal to be able to
replace the generic labels of the General Reference Model (such as "Lower
Layers") with specific names based on the specific technology being considered
in the subsection (e.g., "LLC" in the MIH Reference Model for 802.3), without
touching anything else.
The use of the General Reference Model figure as a template for the following
figures was the simple rationale for the proposal that we submitted in Reference
(2) of your exchange (actually barely mentioned in your discussion). Could you
elaborate on your reasons to reject this approach?
Thank you,
Andrea
Koora Kalyan Com Bocholt wrote:
>
> Hi Ulises,
>
> at first thank your for the comments and for keeping up the discusssion.
> Indeed there are many similarities between different representations. The
> main background why we put up the figure is to have a simple but effective
> and abstract figure.
>
> >1) Ref (1) shows the transport of MIH services between Lower Layer at the
> >network side and 802.21 MIH function as a local interface. However there
> >are other cases to consider. For example, in ref (3) we show this scenario
> >as the collocated case. However we also show that these services can
> >transported over higher layer transport or layer 2 as well. Furthermore
> >in ref (3) we stress that at the network side there is no direct
> communication
> >between 3GPP/3GPP2 lower layers and the MIH function.
>
> In Ref(3) you have elaborated the network side too whereas in Ref(1) it is
> abstract. I feel Ref(3) is subset of Ref(1). Further, there is a new entity
> called "MIH Network Entity" apart from MIHF. The function of this entity is
> not clear to me.
>
> >2) In ref (3) 3GPP and 3GPP2 communicates toward a MIH Network Entity using
>
> >higher layer transport. This is not described in ref (1)
>
> Infact it is there, MIHF communicating with Upper Layers. And upper layer
> is communicating with MIHF peer over higher layer protocols.
>
> >3) However the scenario where just a L3 interface is used to communicate
> >between two MIH peers is not described. This is depicted in ref (3)
> >as double-headed arrow that goes from MIH to MIH simply using a Higher
> >Layer Transport
>
> Yes, that is the reason we proposed to add it in our reference model.
>
> >4)...Here I have a comment and a question: If it is already included
> >in the box, why would we need to specify a L2 transport? ...
>
> The reason behind this is to keep the mechanism of L2 transport independent
> of media (as in Ref(2)). An example to this is typical Ethernet frame.
> Though it is 802.3, it can be carried over different medias like 802.xx.
> We can also think here of PPP, ATM or what else.
> The representation is some what similar to stating "higher layer", here
> too we are not mentioning whether it is TCP or UDP or some other protocol.
> Presently, it is clear to all it will be IP.
>
> >...Also from ref (1) the common layer 2 transport (or lower layer) depicted
>
> >in the figure indicates that both 3GPP/3GPP2 and 802 components used the
> >same L2 transport, this is not accurate...
>
> As I mentioned, the intention was to put an abstract figure which tries to
> cover all the concepts. Again, the model you mentioned can be seen as
> sub-set
> of the it.
>
> >...1) Over the management plane (e.g.,through the introduction of a new an
> >action frame format), and 2) Over the Data Plane using LSAP (through the
> >introduction of a new ethertype).....
>
> >From my understanding both are layer 2.
>
> I have noted that you have changed the 802-Interface at client side in the
> doc attached to the email. I like it better than the previous diagramm :-)
> The point which needs a clarification from my side is, how MIHF communicates
>
> with MGMT (over SAPs or over Transport protocol). This question is also
> valid
> for all local interactions.
>
> With best regards,
> Kalyan
>
> -----Ursprüngliche Nachricht-----
> Von: Olvera-Hernandez, Ulises
> [mailto:Ulises.Olvera-Hernandez@InterDigital.com]
> Gesendet: Montag, 14. November 2005 21:39
> An: Koora Kalyan Com Bocholt; STDS-802-21@listserv.ieee.org
> Betreff: RE: [802.21] Comments on Ref. Model
>
> Hi Kalyan,
>
> I noticed that in the introduction you referred to two contributions
> 21-05-0413....(let us call it ref (1)) and 21-05-0423..-(let us call it ref
> (2)) where as I understand you based the document for discussion. I would
> like us to consider also contribution
> "21-05-0425-00-0000-InterDigital3GPPAmendments" as it is addressing the same
> issue (let us call it reference (3) for the purpose of this discussion). If
> we look at section 5.1.1 from ref(3), the proposed reference model is
> fundamentally the same reference model that we agree to use for our
> presentations to both 3GPP and 3GPP2. I find that this model looks quite
> similar to the one you are proposing except for the
> following:
>
> 1) Ref (1) shows the transport of MIH services between Lower Layer at the
> network side and 802.21 MIH function as a local interface. However there are
> other cases to consider. For example, in ref (3) we show this scenario as
> the collocated case. However we also show that these services can
> transported over higher layer transport or layer 2 as well. Furthermore in
> ref (3) we stress that at the network side there is no direct communication
> between 3GPP/3GPP2 lower layers and the MIH function.
>
> 2) In ref (3) 3GPP and 3GPP2 communicates toward a MIH Network Entity using
> higher layer transport. This is not described in ref (1)
>
> 3) Ref (1) shows communication from MIH function in the client station to
> its peer at the Network through a higher layer transport. This is consistent
> with ref (3). Then the interface goes through what it is referred to as
> 'Higher Layer' before it communicates with the MIH peer. This is very
> similar to ref (3) for case where the interface goes through the MIH Network
> Entity (e.g., the Upper Layer being part of the MIH Network Entity). However
> the scenario where just a L3 interface is used to communicate between two
> MIH peers is not described. This is depicted in ref (3) as double-headed
> arrow that goes from MIH to MIH simply using a Higher Layer Transport.
>
> 4) You also indicate that the management plane has been replaced by what it
> is referred to as L2 transport and that the Management Plane is technology
> specific and therefore it is already covered in the corresponding box. Here
> I have a comment and a question: If it is already included in the box, why
> would we need to specify a L2 transport? Also from ref (1) the common layer
> 2 transport (or lower
> layer) depicted in the figure indicates that both 3GPP/3GPP2 and 802
> components used the same L2 transport, this is not accurate. Furthermore, we
> have discussed two different mechanisms to send MIH information both peer to
> peer and locally: 1) Over the management plane (e.g.,through the
> introduction of a new an action frame format), and 2) Over the Data Plane
> using LSAP (through the introduction of a new ethertype). It is not obvious
> how the "Lower layer Transport" transport handles these two mechanism, in
> particular considering that they interface between the LLT and the MIH
> function is depicted as a local interface. This might be accurate for
> locally generated events but not for peer to peer remote events.
>
> I have taken some of the concepts that you introduce and they are now
> reflected in a newer version of fig.3 from ref (3). I added both snippets
> from this e-mail and fig.3 from ref (3) to your document and I'm sending it
> back attached to this e-mail. I enabled change tracking within the document,
> although changes are quite obvious. Comments are appreciated.
>
> Regards,
> Ulises
>
> -----Original Message-----
> From: Koora Kalyan Com Bocholt [mailto:kalyan.koora@SIEMENS.COM]
> Sent: Thursday, November 10, 2005 8:32 AM
> To: STDS-802-21@listserv.ieee.org
> Subject: [802.21] Comments on Ref. Model
>
> Hello all,
> after going through couple of presentations/comments, we had some internal
> discussions on the reference model. Please find our point-of-view in the
> attached document. This can be discussed in detail later in the IEEE
> meetings or on the reflector.
>
> Awaiting your comments,
> with regards,
> Kalyan