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Re: [802SEC] Mobile Broadband Wireless Access--distinctionbetween the ECSG and 802.16 SG




Dear SEC Colleagues,

I agree with Paul that the two mobile broadband PARs before the SEC have a lot in common. However, the question before us is not simply "Which one do we approve?" Instead, the choices we are have are "either, both, or neither". I'd like to discuss this from an SEC perspective, not from an 802.16 perspective. While I don't pretend to be unbiased, I think I can see the issues from a wide angle.

Here are three basic ways to address the problem:

(1) Approve either the 802.16e PAR or the MBWA SG PAR and reject the other on the basis of overlap. 802.16 believes that the natural evolution of its broadband wireless access technology is to allow its terminals (in licensed bands below 6 GHz) to move during operation. The MBWA SG would like 802 to develop, from scratch, a standard to cover mobile broadband wireless access. The SEC could choose one of these two options. Since the SEC is not an ideal forum for technical decisions, it would probably have to look beyond technical issues and delve fairly deeply into the Five Criteria.

(2) Identify overlap and, if warranted, fix it; then approve both PARs. Since both PARs can be revised during the Plenary session, the potential overlap could be addressed during the week. My impression is that intent of the two Study Groups is somewhat different, and it is possible that the different intentions could be made more explicit within the PARs. Addressing this problem may require thinking more deeply about the differences than to simply say that one is for "high mobility" and one for "low mobility". In the past, 802 has found a way to distinguish its wireless standards without invoking station speed as a differentiator, and I don't see that we need to start now. Furthermore, speed would be an incomplete and non-neutral way to make a distinction because, instead of drawing a line between the two applications, it would limit one to low speeds while placing no limits on the other.

(3) Look at each PAR independently on its own merits and decide whether either is worthy of approval, rejecting both if warranted. I would specifically like to raise the issue that one or both PARs might overlap with existing standards outside of 802: namely, in the mobile telecommunications business. Standards for third-generation (3G) mobile wireless have already been developed, at enormous cost and huge political ramifications, by many of the world's national and international standards-developing organizations. Many of these SDOs have subsequently banded together into partnerships to refine and implement those standards. The SEC needs to think about the wisdom of going into competition with these elephants. It needs to consider whether it is stepping over a line and, if so, it needs to estimate the chances of competing successfully and weigh the possible consequences. Consider, for example, that 3G SDOs trying to interwork their systems with 802.11 LANs have scrupulously avoided treading on the toes of 802. The SEC needs to consider the impact on 802 should we be less than scrupulous in return. Here is some material to consider:

*One of the major U.S. 3G developers is TIA's TR-45. A recent announcement of a TIA teleconference on WLANs, by TIA's Director of Standards Development & Promotion, was posted to the 802.11 reflector. It included this: "Cheryl Blum, Chair of TR-45, reported on a discussion which was held the previous day at the TR-45 plenary on the role of TIA with regard to Wireless LAN standards and interoperability with TIA air interfaces. The concern expressed by TR45 was preventing overlap of work. IEEE is already the recognized expert in the standards arena for standards development related to WLAN and there is no need to step on toes or to duplicate work. Certain boundaries need to be defined for TIA when considering the technical areas that TIA could pursue."

*The same announcement referenced a visit I made to T1P1, the other major U.S. 3G developer, at their invitation following the initiation of 802.16's mobile work. The visit took place after 802 had established two Study Groups in this mobility area, and Mark Klerer (Chair of the MBWA SG) also attended. The record of the meeting <http://ftp.tiaonline.org/TechCommittee/Working/2002September/TC-20020905-012_T1P180216meetingreport.doc> shows that T1P1 was enthusiastic about joint work (responding positively to my suggestion of a handoff tutorial at the November Plenary). On the other hand, the report also shows significant concern on the part of T1P1 regarding 802 efforts that that might tread on their territory.

My bottom line is that we need to be careful with both PARs lest they put 802 into an encroaching position.


Overall, I suggest that the best way to tackle this problem is with a combination of (1), (2), and (3), like this:

(a) Will the 802.16e PAR be good for 802? If so, then approve it.
(b) Will the MBWA SG PAR be good for 802? If so, then approve it.

However, if (a) and (b), then:
    If the overlap between the two PARs is tolerable then:
        Approve both
    Else (If the overlap between the two PARs is intolerable)
        If the proposing groups resolve the overlap, then:
            approve both PARs
        Else (if the proposing groups can't resolve the overlap)
            choose one, reject both, or charter further Study Group activity

These cases get pretty complicated. As an SEC member, I would expect both proposing groups to participate in working through all this.

In summary, I recommend that the SEC view its options broadly, considering the interests of 802, and not get hung up with the battle between two proposals.

Regards,

Roger


>Dear SEC members,
>
>Both the Executive Committee Study Group on Mobile Broadband Wireless Access and the 802.16 Mobile Wireless Access Study Group have submitted Project Authorization Requests for projects that, as far as I can tell from the PARs, address the same market and application space.  This concerns me.
>
>The only substantive difference in the PARs that I can see is that the 802.16 SG proposes to amend the 802.16 MAC/PHY to enable mobile operation, while the ECSG does not presume using the 802.16 standard as a starting point.  This confuses me-when we approved the 802.16 SG in July, it was to focus on enhancements to the 802.16a PHY/MAC for 'limited mobility' in the 2-11GHz band, whilst the ECSG was targeting 'high mobility' in the sub 3.5GHz band.  This established some, albeit small, distinction between the ECSG (0-3.5GHz, up to 250km/h) and 802.16 SGs (2-11GHz, limited mobility) activities.  Now, the gap has narrowed-narrowed to the point that I think the SEC must consider whether or not it makes sense to have two projects with such similar scope.
>
>I would like to hear what other members of the SEC think about the overlap between these two PARs-any opinions out there?
>
>Regards,
>
>--Paul Nikoich