Definitions - ADSL, ADSL2+ and VDSL

[Dolby]

What is ADSL, ADSL2+ and VDSL?

My understanding is VDSL is the same speed up/down and it consists of a fibre backbone (ie up to your complex) with copper the rest of the way?

ADSL2+ is just a more advanced algorithm of ADSL - and uses the same modem?

Both ADSL/ADSL2+ is copper all the way and up/down speed is different? And use a different modem?

 

[Johnatan56]

Wikipedia lifted:
ADSL ANSI T1.413-1998 Issue 2 ADSL 8.0 Mbit/s 1.0 Mbit/s 1998
ADSL ITU G.992.1 ADSL (G.dmt) 8.0 Mbit/s 1.3 Mbit/s 1999-07
ADSL ITU G.992.1 Annex A ADSL over POTS 12.0 Mbit/s 1.3 Mbit/s 2001
ADSL ITU G.992.1 Annex B ADSL over ISDN 12.0 Mbit/s 1.8 Mbit/s 2005
ADSL ITU G.992.2 ADSL Lite (G.lite) 1.5 Mbit/s 0.5 Mbit/s 1999-07
ADSL2 ITU G.992.3 ADSL2 12.0 Mbit/s 1.3 Mbit/s 2002-07
ADSL2 ITU G.992.3 Annex J ADSL2 12.0 Mbit/s 3.5 Mbit/s
ADSL2 ITU G.992.3 Annex L RE-ADSL2 5.0 Mbit/s 0.8 Mbit/s
ADSL2 ITU G.992.4 splitterless ADSL2 1.5 Mbit/s 0.5 Mbit/s 2002-07
ADSL2+ ITU G.992.5 ADSL2+ 24.0 Mbit/s 1.4 Mbit/s 2003-05
ADSL2+ ITU G.992.5 Annex M ADSL2+M 24.0 Mbit/s 3.3 Mbit/s 2008

http://en.wikipedia.org/wiki/Asymmetric_digital_subscriber_line

VDSL ITU G.993.1 VDSL 55 Mbit/s 3Mbit/s 2004-06-13
VDSL ITU G.993.2 VDSL2 100 Mbit/s 100 Mbit/s 2006-02-17

http://en.wikipedia.org/wiki/Very-high-bit-rate_digital_subscriber_line


The differences are:
The exchange
Routers

Both use copper last mile.

 

[cavedog]

Well in terms of what Telkom limits each technology.

ADSL max would be 4Mbps down and 512k up unless you have a 10Mbps line and FORCE your router to use ADSL then it would be 8Mbps down and 800k up.

ADSL2+ max would be 20Mbps or what ever speed will push your SNR down to 6dB. 1Mbps max up that would be the max for adsl2+

VDSL would be max 40Mbps or what ever speed will push your SNR down to 6dB. 3.5Mbps max upload I think.


***The above is what you most likely max you would get if you use are using those technologies with Telkom and they have theoretical maxes also but Telkom don't use that. Also note that you might say be on adsl2+ but only get 2Mbps or 4Mbps due to the distance from the exchange and the exchange itself. I was on 4Mbps on adsl2+ but that was my max because the exchange was served by a ATM uplink which is slow and congest very easy. You can also not be on VDSL and sync @ say 2 or 4Mbps because then something is wrong.

You can get 1 router that are able to run on ADSL, ADSL2+ AND VDSL but they are pricey. Some routers are good though. Most of the routers out today would support adsl and adl2+ at least but I guess you could still get the ADSL only routers but I don't think they are easily available.

 

[MickeyD]

Telkom's limits...

ADSL - 10Mbps down and 1Mbps up

ADSL2+ - 20Mbps down and 1Mbps up

VDSL2 - 40Mbps down and 3Mbps up

 

[mrudling]

Telkom's limits...

ADSL - 10Mbps down and 1Mbps up

ADSL2+ - 20Mbps down and 2Mbps up

VDSL2 - 40Mbps down and 3Mbps up

Telkom limit ADSL2+ upload to 1Mbps

Modulation type G.992.5-A
Actual rate (up) 1020 kbps
Actual rate (down) 20480 kbps

 

[Dolby]

Thanks guys

Thought we had a faster unlink available with these new offerings :/

 

[MickeyD]

Thanks guys

Thought we had a faster unlink available with these new offerings :/

FTTH - 100Mbps

 

[Impulse_One]

Telkom's limits...

ADSL - 10Mbps down and 1Mbps up

ADSL2+ - 20Mbps down and 1Mbps up

VDSL2 - 40Mbps down and 3Mbps up

Hold on...

I thought that 10Mbps is only available on ADSL2+, since just ADSL D.dmt (one used for 4Mbps) handles up to 8Mbps as per table above from wiki.