re: Taking Misinformation/Disinformation out of HSCSD
Are we making any headway? <g>
<< Illmarinen, you are insufferably patronizing. >>
I have read each post of Ilmarinen to you on this subject, and all I can say is it is somewhat difficult not to appear patronizing, which I don't think is Ilmarinen's intent, and it sure isn't mine, but I probably appear to be just as patronizing.
For starters, your perceptions as offered here about HSCSD are not based on much fact, and it appears to me that Ilmarinen has attempted to politely offer some "learning".
Time to be "intellectually honest" as Ilmarinen would say, as I am seeing few signs of rigor. You are asking questions that for some reason you are reluctant to research yourself.
As you will soon be able to tell, as you read, this post was constructed over time, starting before you started asking questions recently, so if it appears choppy, patronizing, or redundant, I'll apologize in advance.
BTW: I am trying to finalize a FAQ on HSCSD that I started last evening. I will publish it shortly. When it is published, you may wish to do some research prior to raising an eyebrow, or immediately challenging statements in it. Look before you leap.
<< Why pay good money for slightly faster (14.4 max vs. 9.6 max) data transfer that is deficient and buggy? >>
Because even though 14.4 max is 50% greater 9.6 max that is not the speed of HSCSD which today maxes at speeds considerably higher than that, and that is before compression, spooling and optimization are added ... and HSCSD lends itself well to all three.
On wireless networks, bugs get worked out. They appear to be pretty well worked out with HSCSD and we are now entering the full commercial phase of deployment, with handsets coming on board rapidly. One year from now we will be at the same stage with GPRS, and one year after that with WCDMA.
Have no fear, the bugs in 1xRTT will be worked out. It may take awhile.
The result will be worth it.
<< Where and when are the business users going to be using HSCSD? In metropolitan areas where many individuals will be competing for time slots.>>
Corporate Road warriors use data (usually on laptops today) in metro areas, in the near suburbs, and the boondocks, and they use it any hour of the day, and most particularly, the off peak evening, because during the day, difficult to find a wireline dataport.
Wireless data, at meaningful HSCSD rates, will allow them to be more productive, and in fact use data communications more often in a mobile environment, because they don't (won't) need to find a dataport to plug into.
<< I can see the quality of service for individual users becoming degraded as HSCSD enabled carriers are tempted to allot slots to high-paying corporate users. >>
Network Planning, Network Additions, QoS, & Network Management, will be used to alleviate this, and so will the addition of Smart Antennas, and Data compression, data optimization, and data spooling.
Sprint PCS faces the same issues as they move to data and are looking to technology (beyond 1xRTT) to solve these issues. Oliver Valente has commented on this frequently, while Levine says "we don't need more spectrum ... in this decade" which means technology better be there soon.
The question is, is the corporate user worth it? You have already answered that in prior posts.
<< A Finnish carrier has actually lowered rates for HSCSD users who use more than one additional time slot. >>
Now that HSCSD is deployed, and debugged, creative pricing plans can be employed. QoS kicks in. Off peak rates are applied after 2200 hours, when a road warrior is doing e-mail, and replicating to the server, in his hotel room, in the lounge downstairs. Been there, done that, still doing it.
Same will happen with GPRS.
<< Clearly, the money is in corporate use, and the Finnish company is obviously luring them in. >>
Clearly it is. Lure em in with VAS, and lock em up. That is marketing. HSCSD complements GPRS so GPRS use will increase, and perhaps so will voice MOU. bottom line is higher APRU,
All the carriers with enough vision to do so, are doing it. More will be added. Early bird gets the worm.
<< As to error correction, it appears that HSCSD cannot reach decent speeds with it in place >>
... but now we know it can.
Your "lack of error correction" was a red herring, and I guess you don't understand the what, why, and wherefore of it. Understandable, I guess. If my FAQ and Ilmarinen's patient explanations to you do not clear it up, you will need to do some "rigorous" outside reading.
<< What I apparently don't understand, and which I realize now, is that the elimination of this GSM error correction technique boosts data speed per time slot to 14.4 >>
It was not an elimination, it was a MODIFICATION that in conjunction with revised channel coding increased the data rate on each time slot.
<< Handoff is tricky, too, particularly if more than two slots are used. >>
You keep saying that.
Not so tricky evidently, depending on mode, and mode change is automatic.
Do you know the two modes HSCSD operate in? Be rigorous.
I had to be rigorous on that one, because it took me a bit to wrestle it done - being rigorous.
Much (but not all) of HSCSD usage will be in a fixed location, but there is mobility as I commented, which corporate customers are willing to pay for, and it gets them off wireline, so there is a cost tradeoff for their own justification of increased wireless usage and $ spent.
<< Let's see. GSM transmits data at 9.6 kbps. Error-corrected HSCSD supposedly is at a speedy 14.4. >>
There you go again.
You are correct, except you left out "on each of (multiple) time slots", and neglected to mention those "modes of operation".
<< I doubt that more than 28 kbps will be offered by most networks. The only device I have seen that offers more than 28 kbps data speeds (up to 43 kbps) is the Nokia 9210 Communicator. The 7000 series device is limited to 14.4. PC cards are available, too. >>
You doubt wrong, again. <g> Orange is at 28 kbps data speeds now but plans to go higher. Several (like D2 Netz which are higher under certain circumstances). Devices of course play a part, but you forget to look around, and you are looking at yesterday, not today and not tomorrow.
So currently here are the data rates of HSCSD on a German Network (Vodafone D2-Netz) - and bear and mind the 2nd phase of the standard allows for up to 8 time slots:
Channels Channel coding 9.6 kbit/s Channel coding 14.4 kbit/s
1 9,6 kbit/s 14,4 kbit/s
2 19,2 kbit/s 28,8 kbit/s
3 28,8 kbit/s 43,2 kbit/s * / 38.4 kbit/s **
4 38,4 kbit/s 57,6 kbit/s * / 38.4 kbit/s **
* theoretical value, which is achieved on the air interface in the D2-Netz
** only with connections to ISDN receiving stations, which support the V.110-Standard
You also neglected to mention the original Nokia Phone Card or Nokia 6210, which will be replaced by the 6310 (GPRS/HSCSD) or the sexy new Ericsson, or a host of other devices coming on stream from Siemens and such.
Check out the Phone Card and the 6310 on the Nokia site and read the FAQ there.
<< If error correction is not so big a deal, why did Nokia apparently slow down HSCSD's speed to incorporate it? >>
They did NOT slow anything down. They sped it up with the new coding scheme with modified error correction. (pursuant to the HSCSD standard they helped author) which is one of several (flexible) ways HSCSD is able to offer data rates comparable to a V.90 modem and when compression is added or more time slots pursuant to the phase 2 standard, ISDN speeds (64 kbps to 128 kbps less a little overhead when two channels are paired in ISDN PRI as opposed to BRI).
Now remember something also. Nokia participates in the development of open standards. They do some development while the standard is being developed, and then finalize development of the standard once the standard is finalized, and when they do they add their own bells and whistles.
In the case of HSCSD they were instrumental in having the standard created, and were the first to commercialize it, while other vendors (Nortel a good example, with more limited R&D resources and focused elsewhere - on GPRS, WCDMA, & 1xRTT).
<< Interesting to determine whether that on both uplink and downlink. Doesn't really say, would be interesting to know. >>
My impression is that this is flexible but I am not really certain. I have seen some data that suggests that typically 3 time slots might be used for the downlink (43.2 kbps) and one for the uplink (14,4), but I have also seen information that leads me to believe that communications can take place both ways at max rate depending on mode (transparent v. non-transparent) and availability of time slots.
<< GPRSux so de-evolve and congest the networks by ripping out error-correction and giving GSM another name. Not a great way to evolve. >>
It is all GSM, all the way to 3GSM, and it is evolution not deevolution, and of course there is error correction which while reduced only impacts by reducing the cell coverage area for a HSCSD user.
As for congestion, a carrier can do what e-plus did - put in more base stations - which better prepares them for GPRS, and there is enough flexibility allowed in managing HSCSD that congestion can be minimized or
alleviated.
All in all, after learning a bit more about HSCSD, I now understand why Nokia elected to supplement its packet based development efforts on WCDMA & GPRS with the circuit-switched HSCSD effort.
For one thing, with 30+ networks with 90 million subscribers out there, there is a substantial ready market for the new (but GPRSless) 9210 Communicator, which eventually will be available for GPRS, EDGE, and WCDMA as well, (hopefully) as cdma2000.
I now understand why Jorma said their would be an extensive market for the new Communicator.
Carriers benefit, Corporations benefit, End Users benefit. Investors benefit.
That is a Win Win Win Win.
My initial impression was that HSCSD would be VERY short lived, and GPRS would be replacative.
It will not be, it will be complementary, although eventually 3GSM (WCDMA) which currently has a 64 kbps circuit-switched mode, will replace it.
While HSCSD may not be the greatest thing since sliced bread it potentially accelerates the shift from voice to data, until the real thing (cdma2000 or WCDMA) comes along.
As mentioned, I am in process of compiling a HSCSD FAQ in case you wish to scan it. It is as "intellectually honest", as I could make it, on short notice, even though there are not a lot of links to sources, because I did not have time to go back and find them from clippings made and annotated over the last month.
In the meantime feel free to be rigorous.
Whew,
- Eric - |
