ADSL needs POTS to work?

[schurtek]

According to Telkom, I have to have a Plain Old Telephone Service in order to make use of ADSL... now this seems far fetched to me.

ADSL and POTS are two completely different technologies and two completely different networks that simply make use of the same copper pair.

This is made possible with the DSLAM which simply filters out the low frequency voice signal and sends it to the POTS network, and the high frequency ADSL signal and sends it to the ADSL cloud.

In my limited understanding of the universe, I would imagine that if we loose the voice, we can achieve higher speeds (hopefully in my uplink) as they have done in other countries?

I am not using my ADSL line to make calls, I have VOX and Virgin for that. Why do I have to pay for a telephone service then?

 

[gifs]

You have to pay for the telephone line so that Telkom can make money.

 

[Nod]

Strictly speaking, Telkom don't have to connect the wire to the exchange. This, IMO, was a big mistake because they could have made the ADSL offering a stand-alone product OR an add-on for telephony.

 

[Syndyre]

There's no technical reason, its just a business decision and not a very good one.

 

[Mr_Kruger]

There's no technical reason, its just a business decision and not a very good one.

No, it is a technical decision!

In my limited understanding of the universe, I would imagine that if we loose the voice, we can achieve higher speeds (hopefully in my uplink) as they have done in other countries?

Forget it.

In Germany you get ADSL only invariably over Annex_B profile, which is much worse.

Be happy that you still have Annex_A. (=ADSL over POTS)
The german telephone network is 100% digital, so our DSLAMs are not made for Annex_A profiles.
It doesn't matter if you need telephone or not, you will always get an Annex-B profile (ADSL over ISDN) here.
Annex_A is technical not available for us!

Annex_A = ADSL over POTS -> frequency from 25 kHz to 1,1 MHz is usable for ADSL(1)
Annex_B = ADSL over ISDN -> only frequency from 138 kHz to 1,1 Mhz is for ADSL!

That's a loss of 113 kHz for us. (= ca. 1,5 mbps)
AND it's a loss of range, because the lower frequency is the best. (so some villages don't have any DSL)

Your 25 kHz loss by POTS is NOTHING against it.


The only way for you to get more speed: Using a higher frequency & rate-adaptive-DSL like ADSL2+

ADSL2+ is using up to 2,2 mhz.

 

[schurtek]

No, it is a technical decision!
Your 25 kHz loss by POTS is NOTHING against it.

it's not the 25khz I am complaining about... it's the fact that I have to buy a service I am not using...

In todays day of technological advancement and integration, we should be paying a fee for the cable connection, and then a seperate fee for telephony connection or DSL connection.

 

[Mr_Kruger]

it's not the 25khz I am complaining about... it's

But you imagined more speed by not using POTS.

it's the fact that I have to buy a service I am not using...

In todays day of technological advancement and integration, we should be paying a fee for the cable connection, and then a seperate fee for telephony connection or DSL connection.

This would not save much money.
Normally the fee for the cable connection is included in the fee for telephony.
But yes, it should be offered "unbundled" even though.

We don't have unbundled ADSL available too, but it will be etablished in Q4/2008.

 

[schurtek]

But you imagined more speed by not using POTS.

I was merely imagining something else to do with that band...

 

[ranger]

According to Telkom, I have to have a Plain Old Telephone Service in order to make use of ADSL... now this seems far fetched to me.

Technically, you need a POTS line (copper to your house) to be able to use ADSL.

In my limited understanding of the universe, I would imagine that if we loose the voice, we can achieve higher speeds (hopefully in my uplink) as they have done in other countries?

No, in most cases voice should have no effect at all. Higher speeds are not due to dropping voice, but due to implementing ADSL2+.

See http://en.wikipedia.org/wiki/Asymmetric_Digital_Subscriber_Line and http://en.wikipedia.org/wiki/ADSL2 for the frequence plans which will show you why voice should have no impact on the speed.

The ADSL line reach vs line speed graph may also be of interest:
http://en.wikipedia.org/wiki/Image:ADSL_Line_Rate_Reach.gif

I am not using my ADSL line to make calls, I have VOX and Virgin for that. Why do I have to pay for a telephone service then?

As far as I know this is a regulatory requirement at present (but I could be wrong).

 

[schurtek]

According to Icasa, providing telephony with data is not required but optional. I know I need a copper pair... but I also know that it doesn't have to be connected to the POTS (PSTN) network. Why am I forced to pay for something I don't want/need.