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I'm a little new at all this technology... Can you explain the difference between a normal 32k and the 64k please. As I understand it, 64k doesn't have much support for voice calls...
 
MTN states HSDPA can reach 14Mb/s. What's Vodacom's long term plans on this.
 
Prometheus said:
MTN states HSDPA can reach 14Mb/s. What's Vodacom's long term plans on this.
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With 64QAM (an encoding method), HSDPA can achieve 14.4Mb/s. This is currently a theoretical limit with no hardware available supporting this capability. Max speed at the moment (but not in production yet) is 3.6Mb/s.

As the technology becomes available, Vodacom will roll it out, normally before anyone else!!
 
vodacom3g said:
Getting around 100ms today, in Midrand.
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Often wondered why wireless have much higher latencies. I mean why can't they build faster ASICS. Signal propagation speeds are for all intensive purposes the same between copper and wireless. (ie close to the speed of light).

The only factor I see is wireless having greater interference and hence greater ECC is needed. Even with ADSL modulation I can't understand why we physically can't see 2ms latencies.
 
wamatt said:
Often wondered why wireless have much higher latencies. I mean why can't they build faster ASICS. Signal propagation speeds are for all intensive purposes the same between copper and wireless. (ie close to the speed of light).

The only factor I see is wireless having greater interference and hence greater ECC is needed. Even with ADSL modulation I can't understand why we physically can't see 2ms latencies.
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It's a function of the number of store and forward devices in the signal path plus the sliding window of the protocol being used.

Each store & forward device (such as a router) must first clock the packet in (at line speed), process it and then clock it out, again at line speed. There are a fair number of these device in the path so all the latencies add up. You then add the sliding window on top of this and you suddenly sit with quite a long turn-around time.

I think you hit the nail on the head with wireless, more devices with more packet processing.
 
wamatt said:
Often wondered why wireless have much higher latencies. I mean why can't they build faster ASICS. Signal propagation speeds are for all intensive purposes the same between copper and wireless. (ie close to the speed of light).
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That is not exactly correct. The signal propagation for wireless through the air is slightly less than lightspeed (299,792,458m/s in a vacuum), and some wireless data gets sent through satellite if i'm not mistaken, so if we assume a round trip of 30,000km the latency will be an extra 100ms. Signal through copper is in fact at infinit speed and it doesn't get passed through satellite, so the latency is dependant on how fast the equipment can respond.
 
vodacom3g said:
Speed through copper is about 0.7 to 0.8C.
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C? :confused:

EDIT:
Ok. Just realised what C means. Technically it's c. From physics I can still remember that although electricity travels very slowly, a lowering or raising in voltage on one end is instantly matched on the other end. Doesn't really matter anyway as I realised afterwards that most of the network works on fibre and light and only the last mile is usually based on copper.
 
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Prometheus said:
C? :confused:

EDIT:
Ok. Just realised what C means. Technically it's c. From physics I can still remember that although electricity travels very slowly, a lowering or raising in voltage on one end is instantly matched on the other end. Doesn't really matter anyway as I realised afterwards that most of the network works on fibre and light and only the last mile is usually based on copper.
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Even in fibre, light travel at less than c, as low as 0.6c. If you can drop the temperature to a few Kelvin, speed in copper approaches c. But nothing is instantaneous.

Except for very long distances such as satellite, the propagation speed is not the major contribution to latency, but rather the clocking in and out at line speed, i.e. so many bits per second. And, of course, the processing time per packet.
 
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ic said:
[post=477105][/post]@v3g, please could you clarify? - MTN have already answered yes in the thread that bwv.9's quoted post links to...
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Hey IC
Tried a Novatel Quad (with Vlive branding) on MTN and it worked fine...
Ciao ~
ScrnScrm
 
Hi Guys
I just got this from Vodacom :

"In order to reward our loyal and high usage customers, Vodacom will offer all subscribers who have been on a data package (either as a tariff plan or an add-on) for 9 months or more, the option to upgrade to a new HSDPA data card.

The above option will be subject to the average value of data revenue generated per month over the last 3 consecutive months.

The cost to the customer for the above option, is as follows:

Average monthly data revenue, inclusive of VAT||Number of months on data package||Cost to customer for upgrade to new HSDPA card

R500 or less||12 or more||R500
R501 to R1 000||12 or more||R250
R1 001 to R2 500||9-12 months||R250
R1 001 to R2 500||12 or more||Free
R 2500 or more||9 months or more||Free"

So basically, if you were an early adopter, and are on a 1GB/month package, you can upgrade to HSDPA for R250.
Cheers ~
ScrnScrm
 
swop

Yes it sounds like a good deal but i was hoping to buy someones old 3g card for a bargain.
 
At last I am getting 3g & HSDPA displayed on my cellphone - appears that with the HSDPA upgrade to the towers in my area, they have reconfigured the 'blindspot' I was in.
Now why did I not get that 3G card on the new messenger contract I took out last month - the free phone is lying in the cupboard gathering dust.
 
ic said:
That's actually weird bcos the '3G & HSDPA enabled' message would be coming from a 2G cell tower, so maybe it's an adjustment to the 2G cell nearby...v3g?
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Yes, it was just the 2G cell broadcast that would have changed.

The radio conditions should not have changed by turning HSDPA on.
 
but you would only get this new 2g cell broadcast if there is actually 3g/hsdpa in that area, right? i mean i know it's probably not all that accurate, but it should at least give you an idea if you're in a coverage area, yes?
 
Unless they have enabled my nearest tower now - I never used to get the '3G enabled' signal in my house.
 
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