Re: [STDS-802-16] [802.16n][DC] Discussion on definition of HR-MS DC and Forwarding to Network
Dear Haiguang, Anh Tuan, Sungcheol, Eldad, and all,
Thank you very much for your participation of the discussion. As Anh
Tuan and Eldad suggested, in order to avoid confusion, we may do not go
deeper in discussion of technical solutions.
As this stage of discussion, I'd like to prepare following draft
consensus text regarding HR-MS direct communication and HR-MS Forwarding
to Network. I will include them in a contribution of proposal of
harmonized text for discussion in 2nd CC of DC RG.
***[Begin of draft consensus text]***
In HR-MS direct communication, the two HR-MSs are the source and the
sink of data, and the data packets are passed from upper layers to MAC
at the source HR-MS and back to upper layers at the sink HR-MS.
In HR-MS Forwarding to Network, a HR-MS forwards user data and control
signaling between a HR-MS and an HR-infrastructure station in a way that
the user data and control signaling do not go through higher layer. The
origination and termination of the user data and control signaling are
at the HR-MS and the HR-infrastructure station respectively and vice
versa.
***[End of draft consensus text]***
SRD is also refereed when I prepare the above text. If you have comments
on the above draft consensus text, please reply this email, or/and
discuss it on the 2nd CC of DC RG. You are appreciated very much.
Best regards,
Mingtuo
---------- Original Message ----------------------------------
From: Wang Haiguang <hwang@I2R.A-STAR.EDU.SG>
Reply-To: Wang Haiguang <hwang@I2R.A-STAR.EDU.SG>
Date: Sun, 24 Apr 2011 11:13:27 +0800
Hi, Anh-Tuan, Ming-Tuo and all,
Please see my comments inline.
Regards.
Haiguang
-----Original Message-----
From: Anh Tuan Hoang [mailto:mbox.hoang@gmail.com]
Sent: Sun 4/24/2011 9:48 AM
To: STDS-802-16@LISTSERV.IEEE.ORG
Subject: Re: [STDS-802-16] [802.16n][DC] Discussion on definition of HR-
MS DC and Forwarding to Network
Hi all,
I just want to modify part of my previous email.
Best regards,
Anh Tuan
2011/4/24 Anh Tuan Hoang <mbox.hoang@gmail.com>
> Dear Ming-Tuo and all,
>
> Thank you for the discussions. I am not responding inline, as I only
have
> the following general comments:
>
> 1. When we attempt to define some capabilities like HR-MS DC or FTN,
the
> only source we should refer to is the SRD. To me, the SRD basically
says:
>
> - HR-MS DC means two HR-MSs can talk to each other *without going
through* an
> infrastructure station.
>
> - HR-MS FTN means one HR-MS can forward data/control messages between
> another HR-MS and an infrastructure station.
>
> 2. When we are trying to give a "deeper/clearer definition", like, how
> similar FTN is to relay, and how many hop/how many forwarded HR-MSs
can be
> supported, we have actually delved into the "technical solutions". And
this
> leads to the confusion because different parties may, subconsciously
:-),
> give their "deeper definition" that just aligns with their "proposed
> solution". I guess this is also what Eldad tried to to suggest when
saying
> "...*The amount of similarity will be determined by technical
> contributions."*
> So I suggest, for definitions, we should aim at somethings very close
to
> (or just use) the SRD. We then can have a discussion topic on, say,
"Pros
> and cons of implementing DC/FTN based on xyz approaches...". This is
where
> the more details can be analyzed.
>
> Best regards,
> Anh Tuan
>
>
> 2011/4/23 Ming-Tuo ZHOU <mingtuo@nict.com.sg>
>
>> Dear Hai-Guang, Eledad, Sungcheol, and all,
>>
>>
>>
>> Thank you very much for discussion. I have several questions:
question 4
>> and 5.
>>
>>
>>
>> Hai-Guang, I am not clear about multi-hop in forwarding to network
and
>> numbers of HR-MS supported in Forwarding to network, could you please
see my
>> comments/question and make me more clear. Thank you a lot.
>>
>>
>>
>>
>>
>> Best regards,
>>
>> Mingtuo
>>
>>
>>
>> *From:* Zeira, Eldad [mailto:Eldad.Zeira@INTERDIGITAL.COM]
>> *Sent:* 2011?4?23? 4:28
>>
>> *To:* STDS-802-16@LISTSERV.IEEE.ORG
>> *Subject:* Re: [STDS-802-16] [802.16n][DC] Discussion on definition
of
>> HR-MS DC and Forwarding to Network
>>
>>
>>
>> Hi Sungcheol, please see my opinion on your comment to question 3
below.
>>
>>
>>
>> Thanks,
>>
>>
>>
>> Eldad
>>
>> Office +1 631 622 4134
>>
>> Mobile +1 631 428 4052
>>
>> Based in NY area
>>
>>
>>
>> *From:* Chang, Sungcheol [mailto:scchang@etri.re.kr]
>> *Sent:* Friday, April 22, 2011 4:41 AM
>> *To:* STDS-802-16@LISTSERV.IEEE.ORG
>> *Subject:* Re: [STDS-802-16] [802.16n][DC] Discussion on definition
of
>> HR-MS DC and Forwarding to Network
>>
>>
>>
>> Hi all,
>>
>>
>>
>> Please see my comments to question 3.
>>
>>
>>
>> Best regards,
>>
>> Sungcheol Chang, Ph.D.
>>
>> Mobile Access Technology Research Team, ETRI
>>
>>
>>
>> *From:* Zeira, Eldad [mailto:Eldad.Zeira@INTERDIGITAL.COM]
>> *Sent:* Friday, April 22, 2011 2:43 AM
>> *To:* STDS-802-16@LISTSERV.IEEE.ORG
>> *Subject:* Re: [STDS-802-16] [802.16n][DC] Discussion on definition
of
>> HR-MS DC and Forwarding to Network
>>
>>
>>
>> Hi Mingtuo, Haiguang
>>
>>
>>
>> Thanks for this discussion. I mostly agree with Haiguang's opinion
but
>> have one question for clarification and several suggestions.
>>
>>
>>
>> Eldad
>>
>> Office +1 631 622 4134
>>
>> Mobile +1 631 428 4052
>>
>> Based in NY area
>>
>>
>>
>>
>>
>> -----Original Message-----
>> From: Wang Haiguang [mailto:hwang@I2R.A-STAR.EDU.SG]
>> Sent: Thursday, April 21, 2011 8:56 AM
>> To: STDS-802-16@LISTSERV.IEEE.ORG
>> Subject: Re: [STDS-802-16] [802.16n][DC] Discussion on definition of
HR-MS
>> DC and Forwarding to Network
>>
>>
>>
>> Dear Ming-Tuo and all,
>>
>>
>>
>> Thanks very much to Ming-Tuo bring this topic to the group.
>>
>> It is very important to have a common understanding these
>>
>> issues.
>>
>>
>>
>> I try to reply the questions based on my understanding.
>>
>>
>>
>> Please see my answer inline.
>>
>>
>>
>> Regards.
>>
>>
>>
>> Haiguang
>>
>>
>>
>>
>>
>>
>>
>> -----Original Message-----
>>
>> From: Ming-Tuo ZHOU [mailto:mingtuo@nict.com.sg]
>>
>> Sent: Thu 4/21/2011 6:20 PM
>>
>> To: STDS-802-16@LISTSERV.IEEE.ORG
>>
>> Subject: [STDS-802-16] [802.16n][DC] Discussion on definition of HR-
MS DC
>> and Forwarding to Network
>>
>>
>>
>> Dear 16n participants,
>>
>>
>>
>>
>>
>>
>>
>> I'd like to trigger discussion of definition of HR-MS direct
communication
>> and HR-MS forwarding to network, since from many discussions it seems
there
>> are some confusion regarding them. In my opinion, it is necessary to
have a
>> clear common understanding of these two functions for development of
>> technical details in a more smooth way. Anyone is welcome to bring
his/her
>> understanding of these two functions by replying this email. I hope
after
>> several rounds of email discussion, we can achieve some consensus
regarding
>> these two functions.
>>
>>
>>
>>
>>
>> The discussion may be started by answering follow questions:
>>
>>
>>
>> 1. what is HR-MS direct communication (DC)?
>>
>>
>>
>> Haiguang: HR-MS direct communication means, the two HR-MSs involved
in the
>> communication are the producer and consumer of the data packets. That
is,
>> the source HR-MS pass the data packet down from upper layer to MAC
and the
>> destination HR-MS pass the packet to upper layer from MAC after
receiving
>> from the air.
>>
>>
>>
>> Clarification: the producer and consumer here are from the view of
MAC. It
>> does not mean the packet is originated from the source HR-MS and
terminated
>> at the destination HR-MS.
>>
>>
>>
>> Eldad: suggest the following text (editorial cleanup, I think it
means the
>> same)
>>
>>
>>
>>
>>
>> The two HR-MS that are in direct communications with each other are
the
>> source and the sink of data. Packets are passed from upper layers to
MAC at
>> the source and back to upper layers at the sink HR-MS.
>>
>>
>>
>>
>>
>> 2. what is HR-MS forwarding to network (FTN)?
>>
>>
>>
>> Haiguang: HR-MS forwarding means the forwarding HR-MS either forwards
the
>> data packet to HR-BS or to the HR-MSs that access the network via the
>> forwarding HR-MS.
>>
>>
>>
>> The forwarded packet will not be passed to upper layer. Instead, it
is
>> forwarded to next hop at MAC layer.
>>
>>
>>
>> Eldad: again I agree with the principle and suggest the following
>> wording:
>>
>>
>>
>> An HR-MS that forwards data to infrastructure node or to another
>> forwarding HR-MS that is attached to an infrastructure node (if
multi-hop is
>> supported) does so without passing any data to or from higher layers.
>>
>>
>>
>> Ming-Tuo: Haiguang (and all), do you think multi-hop HR-MS forwarding
is
>> allowed supported in 16n?
Haiguang: I am not sure how complex it will be.
>>
>>
>>
>>
>> 3. what's difference between HR-MS DC, HR-MS FTN, and HR relay/local
>> forwarding?
>>
>>
>>
>> Haiguang: The differences are:
>>
>> * For HR-MS DC, at the source HR-MS, the data packets are from upper
layer
>> and are passed to upper layer protocol at the destination HR-MS.
>>
>> * For HR-MS FTN, the data packet is forwarded to next hop at MAC
layer.
>> The data packets are not handled by upper layer protocol. HR-MS who
forwards
>> data packet is still an HR-MS. It only has a very simple relay
function and
>> can only support very few nodes, one or two.
>>
>>
>>
>> >From other HR-MSs' view, HR-MS performing the relay function is
still an
>> HR-MS.
>>
>>
>>
>> HR relay is a kind of infrastructure station designed for the purpose
of
>> relay. It is complex and like a BS. It is designed to support many MS
in
>> network access.
>>
>>
>>
>>
>>
>> * Local forwarding means the infrastructure station between MS and BS
>> forwards data packets from downstream HR-station to destination HR-MS
>> without passing it to upstream infrastructure stations.
>>
>>
>>
>> A general case is a HR-RS forwards the data packets from one of its
HR-MS
>> (source) to another HR-MS which is the destination.
>>
>>
>>
>> Eldad:
>>
>> - Not sure what is the meaning of "From other HR-MSs' view, HR-MS
>> performing the relay function is still an HR-MS." - could you please
>> clarify?
>>
>>
>>
>> - >From the SRD, an HR-RS is " A relay that complies with the
>> requirements for relays in this amendment". This is an amendment to
802.16n
>> or 2009, which means that an HR-RS is an RS or ARS as amended by
802.16n. I
>> don't think we need to define it any further, although we'll need to
specify
>> how to implement the requirements we have agreed to in the SRD.
>>
>>
>>
>> Haiguang:
>>
>> My meaning is that the HR-MS should aware that the MS forwards data
>> control for it is an HR-MS. It is not a relay station.
>>
>>
>>
>> Sungcheol Chang:
>>
>>
>>
>> From the discussions and the definitions in the 16n SRD, the
definitions
>> of direct communication and HR-MS forwarding are clearly different in
>> respect of data flow.
>>
>>
>>
>> But I still confuse that the technical difference between HR-MS
forwarding
>> and HR-RS functionalities.
>>
>> Even though HR-RS is an infrastructure node and HR-MS is a user
terminal
>> in nature, I think their names are not important. If devices should
receive
>> packets transmitted by HR-MS, a receiving function within devices is
to
>> receive the packets. Whatever the devices are called like HR-MS or
HR-RS.
>> Their receiving functionalities are similar in nature.
>>
>> I want to know what the technical differences are because we are in
>> developing the AWD text proposal.
>>
>>
>>
>> What happen if we replace 1) HR-MS with HR-RS 2) forwarding HR-MS
with
>> HR-RS in the following definition?
>>
>> The definition of forwarding: "An HR-MS that forwards data to
>> infrastructure node or to another forwarding HR-MS that is attached
to an
>> infrastructure node (if multi-hop is supported) does so without
passing any
>> data to or from higher layers."
>>
>>
>>
>> What happen if we assume a forwarding HR-MS as a HR-RS serving one
>> sub-ordinate HR-MS only? Under this assumption, please list the
technical
>> difference between a forwarding HR-MS and a HR-RS serving one sub-
ordinate
>> HR-MS only. Personally, if we achieve a forwarding HR-MS
functionality with
>> simple modification of HR-RS including signaling procedures, I prefer
the
>> modification rather than defining new function and transmission
schemes
>>
>>
>>
>> Also I'd like to know what forwarding HR-MS is more simple than HR-
RS. I
>> understand that HR-RS has more functionalities than HR-BS and HR-RS
is a
>> infrastructure node. There are two views about complexity. The one is
>> hardware complexity because HR-RS is designed to serve multiple HR-
MS. This
>> complexity is not important issue in respect of functionalities. The
other
>> is functional complexity. HR-RS support two interfaces for relay
operation:
>> 1) interface between HR-BS and HR-RS, 2) interface between HR-MS and
HR-RS.
>> It's clear that forwarding HR-MS has two interfaces also. The relay
>> specification describes relay function in HR-RS, which is required to
relay
>> data and packets to HR-BS or HR-MS. Even though more than HR-BS
>> functionalities, the HR-RS functionalities are selected ones required
for
>> relay operation. From this understanding, please list what forwarding
HR-MS
>> is more simple than HR-RS. It will help me to understand what the
forwarding
>> function is.
>>
>>
>>
>> *[Eldad] the SRD states clearly that forwarding is a functionality of
the
>> HR-MS not the HR-RS (see excerpt below). Obviously there will be
>> similarities between the forwarding function and a relay function as
both
>> support 2 interfaces. That doesn't mean that the two are the same.
The
>> amount of similarity will be determined by technical contributions.
For
>> example only, frame structure can resemble relays (i.e. transmission
in both
>> UL and DL zones) or be in UL only (as some proposed).*
>> 6.1.3.2 HR-MS forwarding to network
>>
>> HR-MS forwarding is defined as the case where the origination and
>> termination of data are at the HR-MS and network respectively and
vice
>> versa.
>>
>> HR-Network shall support HR-MS forwarding of user data and control
>> signaling between HR-MS and HR-BS and between HR-MS and HR-RS. The
control
>> signaling and data transmission for the HR-MS to HR-MS direct link
shall at
>> least be capable of operating within the frequency band that the HR-
BS
>> operates.
>>
>> An association establishment shall be supported.
>>
>>
>>
>> Ming-Tuo: Haiguang, I am not so clear bout "It only has a very
simple
>> relay function and can only support very few nodes, one or two." --
you
>> mean in Forwarding to Network, the a data packet can only be
forwarded to
>> only one or two HR-MSs? Eldad, Sungcheol and all, what's your
opinion?
Haiguang: I mean the number of HR-MSs attached to one forwarding HR-MS
could be
limited. However, there could be many HR-MS within a cell
perform the
forwarding function. That's my consideration. It may help in
simplifying
the design of HR-MS forwarding protocol. But if we can come
out
elegant solution that one forwarding HR-MS can support many
HR-MSs, I am
fine with that.
>> (Ming-Tuo) 4. Is HR-MS forwarding to network is allowed in case that
both
>> HR-MS and the forwarding HR-MS are out of coverage of any HR
infrastructure
>> station?
Haiguang: For this point, I have to say that I did no see this case from
the
use case discussion.
>>
>>
>>
>> (Ming-Tuo) 5. In "Forwarding to network", what the meaning of
"Network" -
>> if there is no backbone connect, is the "Network" there?
>>
Haiguang: I think "forwarding to the network" refers to data flow
direction,
from HR-MS --> HR-BS/HR-RS or other stations. But if it may
cause
confusion, we can replace it with a better terms.
>>
>>
>>
>> Finally, the following is expected to be made:
>>
>>
>>
>> [Consensus: ]
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Thank you very much.
>>
>>
>>
>>
>>
>>
>>
>> Best regards,
>>
>>
>>
>>
>>
>>
>>
>> Ming-Tuo Zhou
>>
>>
>>
>> 16n DC RG co-chair
>>
>>
>>
>>
>>
>
>