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Re: [802.15_GENERAL] [802.19] [802.15_GENERAL] TGn Letter Ballot Support




This thread was getting replies which were not hitting the dot15 reflector so, given the importance of the topic, I will forward this and others as appropriate to the dot 15 general reflector.


At 10:18 AM 5/26/2008 -0400, Carl R. Stevenson wrote:

Steve, et al,
 
I agree with Bill (and others) that the 40 MHz intolerant bit is essentially useless.  If I don't know about it, can't understand when I need to send it, couldn't send it anyway (can't do that modulation), and even if I could send it, I couldn't send it far enough to do any good anyway, it's pretty useless.  This "feature" seems to me to amount to lip service to coexistence and comes across as disingenuous (whether intentionally or not) to me, given it's virtually total lack of utility.
 
There is no practical way for existing 802 standards-compliant devices in the 2.4 GHz band to take advantage of the 40 MHz intolerant bit. 
 
Furthermore, it would be unduly, onerously burdensome to force all of the other 802 standards in the 2.4 GHz band to be ammended to implement the ability to sense .11n operation and transmit that bit - even if they could transmit it over an adequate range for it to be effective (a number of 802 standards use such low power and operate at such short ranges that the practical ability to achieve adequate range is more than highly doubtful).
 
Coexistence has been discussed by the EC as "not breaking other, existing 802 standards" ... it seems to me that the widespread use of 40 MHz channels in the 2.4 GHz band will clearly break a number of existing 802 standards - including legacy 802.11b/g equipment. 
 
Of course, the marketers would love to sell everyone all new gear, but I think that breaking existing equipment wholesale by the billions through the introduction of a disruptive mode such as this is bad customer relations, will ultimately give 802 standards a black eye in the eyes of many, and should not be allowed to happen.  I know that if my 802.15.1 headset stops working with my cellphone, I'll be a very unhappy camper. Likewise if my .11g access point and other equipment stop working (.11g is perfectly adequate for my needs and is built into my, and my wife's, devices - along with 802.15.1 in most cases -  from my access point, to multiple notebooks, to multiple cellphones, to multiple PDAs, to the print server that serves my "E" size color plotter, etc.  The prospect of having to replace all of that equipment because of an arrogant choice in .11n REALLY irritates me ...)
 
I agree with Bill's and John Barr's comment that 40 MHz use should not be allowed in the 2.4 GHz band ... the band is not wide enough and there are too many other 802 standards there to accomodate such use by .11n in that band.
 
While the standard may disallow such use, that's not enough however.  I think that the EC should put its foot down on this impending coexistence disaster and that, with the EC's blessing and instruction, .18 should take point here and warn the FCC and other regulatory agencies of the impending disaster for other devices in the 2.4 GHz band and urge that they adopt rules banning the use of these "double-wide" channels in the band to prevent this "tragedy of the food fight."
 
Therefore, I've added the .18 reflector to the distribution of this so that .18 members can also consider this issue (which I believe they should address as stated above).
 
Regards,
Carl
 
 
 


From: Shellhammer, Steve [mailto:sshellha@qualcomm.com]
Sent: Sunday, May 25, 2008 11:16 PM
To: paul.nikolich@att.net; bkraemer@marvell.com; carl.stevenson@ieee.org; david.cypher@nist.gov; eldad.perahia@intel.com; I_reede@amerisys.com; john.barr@motorola.com; Joseph.Levy@InterDigital.com; Mark.austin@ofcom.org.uk; mjlynch@nortel.com; nada.golmie@nist.gov; ppiggin@nextwave.com; bheile@ieee.org; Shellhammer, Steve; sli@sibeam.com; swhitesell@vtech.ca; vivek.g.gupta@intel.com
Cc: bill.shvodian@ieee.org
Subject: RE: [802.19] [802.15_GENERAL] TGn Letter Ballot Support

I wanted to forward this onto those who are not on the 802.19 reflector

 

Steve

 

From: Bill Shvodian [mailto:bill.shvodian@gmail.com] On Behalf Of Bill Shvodian
Sent: Sunday, May 25, 2008 7:16 PM
To: Shellhammer, Steve
Subject: RE: [802.19] [802.15_GENERAL] TGn Letter Ballot Support

 

Steve, I am not an 802.19 member, but I monitor the reflector so I am not doing a reply-all.  I think that 40 MHz operation should be banned by the FCC and other regulatory agencies.  I think .19 and .18 should be active on this.  There are 2 billion Bluetooth/802.15.1 devices deployed that will be adversely impacted by 40 MHz 802.11n devices.  You and others did a lot of good work to help 802.11 and 802.15.1 devices coexist and this definitely will not help.  The 40 MHz intolerant bits seems nearly useless to me.

 

Bill Shvodian

Director of Standards

NII Holdings

 

From: Shellhammer, Steve [mailto:sshellha@QUALCOMM.COM]
Sent: Sunday, May 25, 2008 2:38 PM
To: STDS-802-19@LISTSERV.IEEE.ORG
Subject: Re: [802.19] [802.15_GENERAL] TGn Letter Ballot Support

IEEE 802.19 TAG,

 

            Paul Nikolich would like the opinion of the 802.19 members on the 40 MHz 802.11n discussion.

 

            If you have an opinion to share please reply-allso that everyone can hear your opinion.

 

Regards,

Steve

 

From: Paul Nikolich [mailto:paul.nikolich@att.net]
Sent: Saturday, May 24, 2008 7:06 AM
To: Shellhammer, Steve
Subject: Fw: [802.15_GENERAL] TGn Letter Ballot Support

 

Steve,

 

What is dot19's opinion on the below debate?

 

--Paul

 

----- Original Message -----

From: Matthew Fischer

To: STDS-802-WPAN@LISTSERV.IEEE.ORG

Sent: Friday, May 23, 2008 10:29 PM

Subject: Re: [802.15_GENERAL] TGn Letter Ballot Support

 

 

I will be voting YES on TGn LB129, and I would urge others who are interested in defending 802.15.x devices' access to the ISMii band to vote YES as well.

 

The current draft of the 802.11 TGn amendment contains normative language describing a mechanism (i.e. the 40 MHz Intolerant bit) that allows non-related devices to signal to the 40 MHz TGn devices that they cannot send 40 MHz transmissions, effectively allowing other users of the ISMii band to restrict the use of 40 MHz transmissions by TGn devices. 40 MHz 802.11 TGn devices are required to obey this signaling whenever it occurs.

 

If 40 MHz operation is forbidden in ISMii by 802.11 TGn, then 40 MHz operation will be implemented as a set of vendor-specific non-standardized modes with variable degrees of good citizenship regarding spectrum sharing and with little or no opportunity for such devices to be controled by other users of the ISMii band.

 

For these reasons, it is in the best interest of 802.15.x technology providers and other users of the ISMii band to vote YES on the TGn-standardized mode of 40 MHz operation that includes specific requirements to force TGn devices to cease 40 MHz operation when requested.

 

 

Matthew Fischer
Nice Guy
+1 408 543 3370 office
+1 650 796 9206 mobile
mfischer@broadcom.com

 

 

From: John Barr [mailto:john.barr@MOTOROLA.COM]
Sent: Friday, May 23, 2008 8:36 AM
To: STDS-802-WPAN@LISTSERV.IEEE.ORG
Subject: [802.15_GENERAL] TGn Letter Ballot Support

As mentioned in Jacksonville, the current draft of TGn includes use of 40 MHz channels in 2.4 GHz spectrum. This will significantly impair ability of other IEEE standards using 2.4 GHz spectrum to coexist with TGn devices running at 40 MHz. Even though the rejection of my comment number 6069 states that there is provision for coexistence with other radio systems using 2.4 GHz spectrum, the actual text for this is informative and does not actually include tests for IEEE 802.15.1 nor IEEE 802.15.4 devices. See attached note to TGn I sent during the Jacksonville meeting. At the one session where there was any discussion on my comment, I spoke against the resolution and no one spoke for the resolution rejecting my suggested change (not to allow any use of 40 MHz channels in 2.4 GHz spectrum). (See attached)

As it current stands there is no clear method to prevent use of 40 MHz channels in 2.4 GHz when IEEE 802.15.1 and 802.15.4 devices are operating in the same spectrum.

You can vote against the current TGn letter ballot by referencing my comment (6069) that is unresolved (not accepted by the submitter) and requesting the same resolution: In 20.3.15 change "When using 40 MHz channels, it can operate in the channels defined in 20.3.15.1 and 20.3.15.2." to "When using 40 MHz channels, it can only operate in the channels defined in 20.3.15.2."

James Gilb may be able to clarify just how to vote on this. Voters who previously approved the original LB can change their vote to disapprove based on this comment.

Thank you for your support.

Regards, John
-- 
John R. Barr (John.Barr@Motorola.com)
Director, Standards Realization - <http://www.motorola.com>
Vice Chairman of the Board, Bluetooth SIG - <http://www.bluetooth.org>
(847) 576-8706 (office) +1-847-962-5407 (mobile) (847) 576-6758 (FAX)



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