upstream/downstream noise margins

hi all

is someone willing to explain what on earth this is? I would imagine this determines what your line can sync at?

for upstream I get

noise margin upstream: 12 db
output power downstream: 5 db
attenuation upstream: 16 db

and downstream I get

noise margin downstream: 24 db
output power upstream: 7 db
attenuation downstream: 29 db

Are these within normal limits?

cheers

depends on the brand of telephone.

inferno said:

depends on the brand of telephone.

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what the F are you talking about man?

HTC_guy said:

what the F are you talking about man?

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Telephones

LOL

sigh

Gamer said:

http://mybroadband.co.za/vb/showthread.php?t=186156

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thanks Gamer

inferno said:

depends on the brand of telephone.

Click to expand...

hahahahahahahaa lolololololol

No does not, those figures indicate that a certain speed of line, those figures are calculated by algorithms for transfer over some channels of the DSL frequency spectrum.

Ideally port to router are supposed to sync with acceptable figures of SNR/Attn, thenDSL link speeds will vary from one user to another based on line/copper conditions, distance, diameter of copper, router, filter, sockets, etc.
e.g SNR minimum is 8db (tolerance of 5 db before port resets) and attn of 60 db (could be 50 db spec), then what will speed be?

answer: possibly 2.3 meg for one and 4 meg for another, or even 7 meg for someone else.

Telkom sells services based on port profiles speed and not based on SNR/Attn, but look at Attn/SNR when link fails and forces speed downgrades. 384k/4096 have an auto rate adaptive setting, the port will step down in 32k until some sort of stability is achieved if/when SNR/Attn are around margins. If anybody can say just by looking at SNR/attn what actual TX will be, they would be guessing an average based on experience.