Re: [STDS-802-11-TGBE] [EXTERNAL] Re: [STDS-802-11-TGBE] EMLSR and EMLMR definitions
Dear all,
> *enhanced multi-link single radio (EMLSR) operation:* A mode of operation
> that allows a non-access point (non-AP) multi-link device (MLD) with
> multiple receive chains to listen on a set of enabled links, then move to
> one link within the set, for the immediately following set of frame
> exchanges.
@Stephen, thanks for the edits, the last version of EMLSR addresses my
initial concerns (not only "moves" rx, but also tx). However, the "...then
move to one link within the set..." still feels too vague. What is being
moved?
Also considering Xiaofei's comment on moving spatial streams vs. moving rf
chains, what about something like:
"...**, and to re-configure one or more receiver and transmiter chains to
transmit and receive** on one link within the set, for the immediately
following set of frame exchanges."
or just:
"... **to increase the number of spatial streams** on one link within the
set..."?
Best regards,
Eduard
> Regarding your second point, I politely disagree. I think it's essential
> to
> define these terms, as it's certainly not clear from clause 35 what these
> EML modes of operation are. I appreciate that this is difficult work, but
> I
> think it's worth persevering with.
>
> Kind regards
>
> Stephen
>
> On Mon, 12 Sept 2022 at 16:56, Minyoung Park <mpark.ieee@xxxxxxxxx> wrote:
>
>> Hi Stephen,
>>
>> The 'move to receive on one link within the set' is not correct. As I
>> mentioned, a non-AP MLD in EMLSR mode doesn't move to receive before the
>> immediately following frame exchanges.
>>
>> If we cannot have a correct definition in Clause 3, it is better not to
>> have it in Clause 3. It is better to rely on the EMLSR subclause in
>> Clause
>> 35.3.17.
>>
>> Regards,
>> Minyoung
>>
>> On Mon, Sep 12, 2022 at 7:45 PM Stephen McCann
>> <mccann.stephen@xxxxxxxxx>
>> wrote:
>>
>>> Massinissa, John,
>>> Thanks for your comments.Perhaps this would
>>> be suitable:
>>>
>>> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>> operation that allows a non-access point (non-AP) multi-link device
>>> (MLD)
>>> with multiple receive chains to listen on a set of enabled links, then
>>> move
>>> to receive on one link within the set, for the immediately following
>>> set of
>>> frame exchanges.
>>>
>>> I am trying to avoid re-introducing the term "Control frame", as I
>>> really
>>> don't think this is appropriate for a definition.
>>>
>>> Kind regards
>>>
>>> Stephen
>>>
>>>
>>> On Mon, 12 Sept 2022 at 16:32, Wullert, John R II (PERATON LABS) <
>>> jwullert@xxxxxxxxxxxxxxx> wrote:
>>>
>>>> Stephen,
>>>> One concern I have with your proposed definition is that while the
>>>> term contains the words "single radio" the definition says "one or
>>>> more"
>>>> which can lead to confusion. Perhaps we need to focus the definition
>>>> not
>>>> on how many radios the device *has *but on how many it *uses *in the
>>>> context of the EMLSR operation. While the former may be one or more,
>>>> I
>>>> believe the latter must be one.
>>>> John
>>>> ------------------------------
>>>> *From:* Stephen McCann <mccann.stephen@xxxxxxxxx>
>>>> *Sent:* Monday, September 12, 2022 10:26 PM
>>>> *To:* STDS-802-11-TGBE@xxxxxxxxxxxxxxxxx <
>>>> STDS-802-11-TGBE@xxxxxxxxxxxxxxxxx>
>>>> *Subject:* [EXTERNAL] Re: [STDS-802-11-TGBE] EMLSR and EMLMR
>>>> definitions
>>>>
>>>> Rubayet,
>>>> I don't think the EMLSR definition is ambiguous. The
>>>> current definition that I propose supports the second of your options.
>>>>
>>>> Kind regards
>>>>
>>>> Stephen
>>>>
>>>> On Mon, 12 Sept 2022 at 16:20, Rubayet Shafin <r.shafin@xxxxxxxxxxx>
>>>> wrote:
>>>>
>>>> Hi Stephen,
>>>>
>>>>
>>>>
>>>> Just for my understanding--why is it better to stay silent and keep
>>>> things ambiguous?? We have had enough discussion in the group that is
>>>> rooted from this ambiguity. I think it is time to clear that out.
>>>>
>>>>
>>>>
>>>> - If EMLSR is only for single radio devices, I think it has to be
>>>> stated in the spec clearly
>>>> - If EMLSR is for both single and multiple radios devices, I think
>>>> it also has to be stated in the spec clearly.
>>>>
>>>>
>>>>
>>>> Best
>>>>
>>>> Rubayet
>>>>
>>>>
>>>>
>>>> *From:* Stephen McCann <mccann.stephen@xxxxxxxxx>
>>>> *Sent:* Monday, September 12, 2022 10:14 PM
>>>> *To:* Rubayet Shafin <r.shafin@xxxxxxxxxxx>
>>>> *Cc:* STDS-802-11-TGBE@xxxxxxxxxxxxxxxxx
>>>> *Subject:* Re: [STDS-802-11-TGBE] EMLSR and EMLMR definitions
>>>>
>>>>
>>>>
>>>> Dear all,
>>>>
>>>> the current definition of EMLSR that I mentioned earlier,
>>>> is silent about how many radios are present in the MLD. I think it's
>>>> best
>>>> left that way.
>>>>
>>>>
>>>>
>>>> Kind regards
>>>>
>>>>
>>>>
>>>> Stephen
>>>>
>>>>
>>>>
>>>> On Mon, 12 Sept 2022 at 16:11, Rubayet Shafin <r.shafin@xxxxxxxxxxx>
>>>> wrote:
>>>>
>>>> Hi Minyoung,
>>>>
>>>>
>>>>
>>>> Do you intend to mean that a device that supports EMLSR can only have
>>>> one radio? If you donâ??t intend to mean that, I think it would be
>>>> better to
>>>> clarify this rather than keeping the definition ambiguous on that
>>>> aspect.
>>>>
>>>>
>>>>
>>>> Best
>>>>
>>>> Rubayet
>>>>
>>>>
>>>>
>>>> *From:* Minyoung Park <mpark.ieee@xxxxxxxxx>
>>>> *Sent:* Monday, September 12, 2022 9:21 PM
>>>> *To:* STDS-802-11-TGBE@xxxxxxxxxxxxxxxxx
>>>> *Subject:* Re: [STDS-802-11-TGBE] EMLSR and EMLMR definitions
>>>>
>>>>
>>>>
>>>> Hi Stephen,
>>>>
>>>>
>>>>
>>>> The EMLSR definitions is still not accurate.
>>>>
>>>>
>>>>
>>>> A non-AP MLD doesn't move to receive on one available link but the
>>>> listening operation includes the receiving function of the initial
>>>> control
>>>> frame on the set of enabled links. A non-AP MLD moves to one available
>>>> link
>>>> on which the initial control frame was received and exchange frames.
>>>>
>>>>
>>>>
>>>> Also deleting 'one or more radio(s)' would be better to avoid
>>>> controversial discussions. (this wasn't in the original definition as
>>>> well)
>>>>
>>>>
>>>>
>>>> The following is my suggestion:
>>>>
>>>> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> operation that allows a non-access point (non-AP) multi-link device
>>>> (MLD)
>>>> with multiple receive chains and with one or more radio(s), to listen
>>>> on a set of enabled links, then move to receive on one available link
>>>> within the set *on which the initial Control frame was received*, for
>>>> the immediately following set of frame exchanges.
>>>>
>>>>
>>>>
>>>> Regards,
>>>>
>>>> Minyoung
>>>>
>>>>
>>>>
>>>> On Mon, Sep 12, 2022 at 5:57 PM Stephen McCann
>>>> <mccann.stephen@xxxxxxxxx>
>>>> wrote:
>>>>
>>>> Eduard,
>>>>
>>>> I agree with the other comments that resources are not
>>>> moved
>>>> in an EMLSR mode, so I prefer my earlier definitions. This is what I
>>>> propose to move forward with:
>>>>
>>>>
>>>>
>>>> *enhanced multi-link multiple radio (EMLMR) operation*: A mode of
>>>> operation that allows any of the stations (STAs) affiliated with a
>>>> non-access point (AP) multi-link device (MLD) on a set of enabled
>>>> links, to
>>>> move receive and transmit spatial streams to one link within the set,
>>>> to
>>>> increase resources on that link, for the immediately following set of
>>>> frame
>>>> exchanges. (#10935, #11820, #12035, #12706)
>>>>
>>>>
>>>>
>>>> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> operation that allows a non-access point (non-AP) multi-link device
>>>> (MLD)
>>>> with multiple receive chains and with one or more radio(s), to listen
>>>> on a
>>>> set of enabled links, then move to receive on one available link
>>>> within the
>>>> set, for the immediately following set of frame exchanges.
>>>>
>>>>
>>>>
>>>> Thanks.
>>>>
>>>>
>>>>
>>>> Kind regards
>>>>
>>>>
>>>>
>>>> Stephen
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> On Mon, 12 Sept 2022 at 14:46, Rubayet Shafin <r.shafin@xxxxxxxxxxx>
>>>> wrote:
>>>>
>>>> Hi Stephen,
>>>>
>>>>
>>>>
>>>> I also disagree with Eduard in the sense that the EMLSR is â??applied
>>>> to a
>>>> single-radio non-AP MLDâ??. EMLSR is a mode of operation, not a
>>>> device-level
>>>> capability. EMLSR can be applied to both single radio and multi-radio
>>>> devices. In other word, a device with multiple radios may elect to
>>>> operate
>>>> on EMLSR mode on a subset of enabled links (EMLSR Links), while other
>>>> radios can operate on non-EMLSR links.
>>>>
>>>>
>>>>
>>>> I prefer your previous definition in this aspect.
>>>>
>>>>
>>>>
>>>> Best
>>>>
>>>> Rubayet
>>>>
>>>> *From:* Minyoung Park <mpark.ieee@xxxxxxxxx>
>>>> *Sent:* Monday, September 12, 2022 2:37 PM
>>>> *To:* STDS-802-11-TGBE@xxxxxxxxxxxxxxxxx
>>>> *Subject:* Re: [STDS-802-11-TGBE] EMLSR and EMLMR definitions
>>>>
>>>>
>>>>
>>>> *Caution:* This email originated from outside of the organization. Do
>>>> not click links or open attachments unless you recognize the sender
>>>> and
>>>> know the content is safe.
>>>>
>>>>
>>>>
>>>> Hi Stephen,
>>>>
>>>>
>>>>
>>>> I disagree with the statement from Eduard. The EMLSR doesn't move
>>>> around
>>>> resources between different links. Each STA's capability is announced
>>>> during the association process and that capability is used in the
>>>> EMLSR
>>>> mode.
>>>>
>>>>
>>>>
>>>> As I commented in the call last week, it would be better to focus on
>>>> the
>>>> EMLMR definition, which is what the commenter is asking for.
>>>>
>>>>
>>>>
>>>> Regards,
>>>>
>>>> Minyoung
>>>>
>>>>
>>>>
>>>> On Mon, Sep 12, 2022 at 5:25 PM Stephen McCann
>>>> <mccann.stephen@xxxxxxxxx>
>>>> wrote:
>>>>
>>>> Eduard,
>>>>
>>>> yes, I think that is reasonable.
>>>>
>>>>
>>>>
>>>> Kind regards
>>>>
>>>>
>>>>
>>>> Stephen
>>>>
>>>>
>>>>
>>>> On Sun, 11 Sept 2022 at 23:43, Eduard Garcia Villegas <
>>>> eduardg@xxxxxxxxxxxxx> wrote:
>>>>
>>>> Dear Stephen,
>>>>
>>>> As far as I understood, EMLSR is the same as EMLMR, but applied to a
>>>> single-radio non-AP MLD. Therefore, I'd use the same phrasing in both
>>>> definitions, based on the EMLMR definition you proposed (which I find
>>>> more
>>>> accurate). Something like:
>>>>
>>>> "*enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> operation
>>>> that allows a single-radio non-access point (non-AP) multi-link device
>>>> (MLD) with multiple receive chains, to listen on a set of enabled
>>>> links,
>>>> then move receive and transmit spatial streams to one link within the
>>>> set,
>>>> to increase resources on that link, for the immediately following set
>>>> of
>>>> frame exchanges.
>>>> "
>>>>
>>>> Note that, in the uplink, the non-AP MLD can choose to use its tx
>>>> chain(s)
>>>> on a different link each time (i.e. not only moves rx chains).
>>>>
>>>>
>>>> Cheers,
>>>>
>>>>
>>>> Eduard
>>>>
>>>> On Mon, September 12, 2022 12:03 am, Stephen McCann wrote:
>>>> > Dear all,
>>>> > thanks for all the further comments on this topic.
>>>> These
>>>> are
>>>> > the some updated definitions that I have produced based on the
>>>> comments:
>>>> >
>>>> > *enhanced multi-link multiple radio (EMLMR) operation*: A mode of
>>>> > operation
>>>> > that allows any of the stations (STAs) affiliated with a non-access
>>>> point
>>>> > (AP) multi-link device (MLD) on a set of enabled links, to move
>>>> receive
>>>> > and
>>>> > transmit spatial streams to one link within the set, to increase
>>>> resources
>>>> > on that link, for the immediately following set of frame exchanges.
>>>> > (#10935, #11820, #12035, #12706)
>>>> >
>>>> >
>>>> >
>>>> > *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> operation
>>>> > that allows a non-access point (non-AP) multi-link device (MLD) with
>>>> > multiple receive chains and with one or more radio(s), to listen on
>>>> a
>>>> set
>>>> > of enabled links, then move to receive on one available link within
>>>> the
>>>> > set, for the immediately following set of frame exchanges.
>>>> >
>>>> > Kind regards
>>>> >
>>>> > Stephen
>>>> >
>>>> > On Sat, 10 Sept 2022 at 11:39, Mark Rison <m.rison@xxxxxxxxxxx>
>>>> wrote:
>>>> >
>>>> >> > And for "all of the following frame exchanges" seems eternal in
>>>> scope.
>>>> >> If this definition is intended to be read by someone lacking
>>>> extensive
>>>> >> 802.11 knowledge then it could say, for "the immediately following
>>>> set
>>>> >> of
>>>> >> frame exchanges"
>>>> >>
>>>> >>
>>>> >>
>>>> >> Or just leave the ending of the condition unstated:
>>>> >>
>>>> >>
>>>> >>
>>>> >> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> >> operation
>>>> >> that allows a non-access point (non-AP) multi-link device (MLD)
>>>> with
>>>> >> multiple receive chains to listen on a set of enabled links, then
>>>> switch
>>>> >> to
>>>> >> one available link within the set.
>>>> >>
>>>> >>
>>>> >>
>>>> >> > I think that at least for emlsr, instead of switch it might say
>>>> >> something like "receive"
>>>> >>
>>>> >> > It turns out that listening on the link on which receive is not
>>>> >> occurring is still possible during the receive
>>>> >>
>>>> >>
>>>> >>
>>>> >> You mean
>>>> >>
>>>> >>
>>>> >>
>>>> >> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> >> operation
>>>> >> that allows a non-access point (non-AP) multi-link device (MLD)
>>>> with
>>>> >> multiple receive chains to listen on a set of enabled links, then
>>>> >> receive
>>>> >> to [on?] one available link within the set.
>>>> >>
>>>> >>
>>>> >>
>>>> >> ? That's not worse, but still doesn't explain the key point, which
>>>> is
>>>> >> that the receive chains are reallocated to be used on the same
>>>> channel.
>>>> >>
>>>> >>
>>>> >>
>>>> >> My suggestion would be:
>>>> >>
>>>> >>
>>>> >>
>>>> >> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> >> operation
>>>> >> that allows a non-access point (non-AP) multi-link device (MLD) to
>>>> >> listen
>>>> >> on a set of enabled links using one radio frequency (RF) chain on
>>>> each,
>>>> >> and
>>>> >> then switch all the RF chains to one of the links for subsequent
>>>> >> single-user multiple input, multiple output (SU-MIMO) operation on
>>>> that
>>>> >> link.
>>>> >>
>>>> >>
>>>> >>
>>>> >> Also, maybe it's because I wasn't there, but I find this definition
>>>> >> rather
>>>> >> confusing:
>>>> >>
>>>> >>
>>>> >>
>>>> >> *enhanced multi-link multiple radio (EMLMR) operation*: A mode of
>>>> >> operation that allows any of the stations (STAs) affiliated with a
>>>> >> non-access point (non-AP) multi-link device (MLD) on a set of
>>>> enabled
>>>> >> links, to switch receive and transmit spatial streams of one
>>>> available
>>>> >> link
>>>> >> within the set, to increase resources on that link, for all of the
>>>> >> following frame exchanges.
>>>> >>
>>>> >>
>>>> >>
>>>> >> I initially read "switch tx and rx" as being that tx becomes rx and
>>>> rx
>>>> >> becomes tx.
>>>> >>
>>>> >> Even if it means "transfer both of them to another link" (i.e. you
>>>> need
>>>> >> to
>>>> >> have
>>>> >>
>>>> >> a "to X" after the "switch"), isn't this a definition of EMLSR?
>>>> What
>>>> >> does EMLMR
>>>> >>
>>>> >> do that EMLSR doesn't do?
>>>> >>
>>>> >>
>>>> >>
>>>> >> Thanks,
>>>> >>
>>>> >>
>>>> >>
>>>> >> Mark
>>>> >>
>>>> >>
>>>> >>
>>>> >> --
>>>> >>
>>>> >> Mark RISON, Standards Architect, WLAN English/Esperanto/Français
>>>> >>
>>>> >> Samsung Cambridge Solution Centre Tel: +44 1223 434600
>>>> >>
>>>> >> Innovation Park, Cambridge CB4 0DS Fax: +44 1223 434601
>>>> >>
>>>> >> ROYAUME UNI WWW:
>>>> http://www.samsung.com/uk
>>>> >>
>>>> >>
>>>> >>
>>>> >> *From:* Matthew Fischer <matthew.fischer@xxxxxxxxx>
>>>> >> *Sent:* Friday, 9 September 2022 14:44
>>>> >> *To:* STDS-802-11-TGBE@xxxxxxxxxxxxxxxxx
>>>> >> *Subject:* Re: [STDS-802-11-TGBE] EMLSR and EMLMR definitions
>>>> >>
>>>> >>
>>>> >>
>>>> >> I think that at least for emlsr, instead of switch it might say
>>>> >> something
>>>> >> like "receive"
>>>> >>
>>>> >>
>>>> >>
>>>> >> It turns out that listening on the link on which receive is not
>>>> >> occurring
>>>> >> is still possible during the receive
>>>> >>
>>>> >>
>>>> >>
>>>> >> And for "all of the following frame exchanges" seems eternal in
>>>> scope.
>>>> >> If
>>>> >> this definition is intended to be read by someone lacking extensive
>>>> >> 802.11
>>>> >> knowledge then it could say, for "the immediately following set of
>>>> frame
>>>> >> exchanges"
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >> On Fri, Sep 9, 2022, 2:19 PM Stephen McCann
>>>> <mccann.stephen@xxxxxxxxx
>>>> >
>>>> >> wrote:
>>>> >>
>>>> >> Dear all,
>>>> >>
>>>> >> thanks for your comments following my presentation of
>>>> >> 11-22-1196r3.
>>>> >>
>>>> >>
>>>> >>
>>>> >> Here are the revised definitions that I presented:
>>>> >>
>>>> >>
>>>> >>
>>>> >> *enhanced multi-link multiple radio (EMLMR) operation*: A mode of
>>>> >> operation that allows any of the stations (STAs) affiliated with a
>>>> >> non-access point (non-AP) multi-link device (MLD) on a set of
>>>> enabled
>>>> >> links, to switch receive and transmit spatial streams of one
>>>> available
>>>> >> link
>>>> >> within the set, to increase resources on that link, for all of the
>>>> >> following frame exchanges.
>>>> >>
>>>> >>
>>>> >>
>>>> >> *enhanced multi-link single radio (EMLSR) operation:* A mode of
>>>> >> operation
>>>> >> that allows a non-access point (non-AP) multi-link device (MLD)
>>>> with
>>>> >> multiple receive chains to listen on a set of enabled links, then
>>>> switch
>>>> >> to
>>>> >> one available link within the set, for all of the following frame
>>>> >> exchanges.
>>>> >>
>>>> >>
>>>> >>
>>>> >> Please let me know if you have any further suggestions. If we can
>>>> >> converge
>>>> >> on suitable text, then I can represent an updated submission next
>>>> week.
>>>> >>
>>>> >>
>>>> >>
>>>> >> Kind regards
>>>> >>
>>>> >>
>>>> >>
>>>> >> Stephen
>>>> >> ------------------------------
>>>> >>
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>>>> >
>>>> >
>>>> ________________________________________________________________________
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>>
>
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