DSL Data Rates

[s.steiner]

Hi,

I have a general question regarding the datarates in dsl-technology. For example when talking about SDSL, I always hear, the maximum bandwidth on a 1-pair link is about 2 Mbit/s. OK, but does it mean 2 Mbit/s in up- and downstream-direction at the same time. Starting an upload and a download at the same time, do both have to run at 2 Mbit/s or each on 1 Mbit/s ? So, does the statement 2 Mbit/s mean combined bandwidth or in each direction at the same time (fullduplex) ?

I have identical questions regarding SHDSL and ADSL (2+).

I would be glad if somebody will have an answer for me.

Thanks and best regards,

Stephan

[Georg Pauwen · Accepted solution]

Hello Stephan,

SDSL has the same upload and download speed, that is, if you get e.g. a 1MB SDSL connection, that means you can have 1MB upload and 1MB download at the same time. I guess you are aware that the difference between SDSL and ADSL is that SDSL does not allow the use of e.g. a telephone line at the same time, which ADSL does.

Regarding SHDSL, you might want to have a look at the following FAQ's:

SHDSL FAQ

http://www.dslforum.org/aboutdsl/shdsl_faq.html

As for ADSL2/ADSL2+, have a look at the following white paper:

ADSL2/ADSL2+ White Paper

http://www.dslprime.com/a/adsl21.pdf

HTH,

GP