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Substate

Weird ADSL Attenuation

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Hi all :).

 

So I've been investigating ADSL2+ and trying to figure out what kinda speeds i'd be getting. Being 4.5km away from our exchange (Acacia Ridge), the exchange map gives an estimate of 4mbits or so. However, one of my mates wanted to know some connection info so I took a screenshot.

 

My modem presented me with the following...

 

Downstream Rate - 1536kbps

Upstream Rate - 128kbps

Downstream Margin - 29db

Upstream Margin - 6db

Downstream Line Attenuation - 13

Upstream Line Attenuation - 10

 

They're the same numbers I see whenever I happen to have the status page up.

 

I'm mainly confused as to whether the 'Margins' are the Signal-to-Noise-Ratio's or whether they are the actual attenuation.

 

So, dear Atomicans, what do you all make of the stuff above? Is it good? Or is it godawful? Should I prove successful in my ADSL2+ adventures, should I be looking forward to some killer speed or should I be expecting only modest performance?

 

Help, advice and opinions would be very much appreciated and please excuse my noobiness :).

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yep Margin= SNR.

With those figures ADSL2+ should work quite well I think.

At the other end of the scale I have

 

Down SNR Margin (dB):11.3

Up SNR Margin (dB): 23.0

Down Attenuation (dB): 63.5

Down Attenuation (dB): 31.5

 

Attainable Rate (Kbps):

Down 2080

up 972

Rate (Kbps):

Down 1536

Up 256

So no point in ADSl 2+ for me, or even full ADSL.

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Most ADSL Pair gain systems (Alcatel CMUX, NEC AM35, etc) have auto Attenuation enabled at the exchange - dont go an hard configer any values in your modem.

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I'm not quite sure what to make of those figures, Substate. They seem exceptionally good if you're 4km from the exchange.

 

I'm 5ish km (I think... I never can remember) from the Sunnybank exchange with 54.5dB downstream attenuation, 12.5dB noise margin and 3.9Mbps sync on ADSL1 (though it's currently 2.7Mbps since I've had line issues and 'node have applied a stability profile to the DSLAM port).

 

You're 4km from the exchange with 13dB downstream attenuation and 29dB noise margin? If that's correct then you should get exceptional performance on ADSL2+ but I'd say you're probably more likely to be on a CMUX or similar which is quite close to your house - or your modem is lying to you about those stats.

 

There's one way to find out, and that is to apply :-)

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amckern's on the money. Applied with iiNet and was told I'm on pair gain, so that explains the (unbelievably) good attenuation and SNR numbers. Applied with Internode for a churn to one of their 1500k ADSL1 plans. If the sync is good it'll be a nice boost over our current connection, so I'm not that bummed. If it all goes well I'll be free of AAPT on Monday sometime and I'll post stats then :).

 

Oh and cheers segger, good to see someone on here is close by.

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