Questions about ADSL in general

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DravidDavid

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#97566 16-Feb-2012 22:39

Back at home I was blessed with an ADSL 2+ connection within 2K's of the cabnet. Our connection was a constant 18Mb/s down (syncing at 23mb/s at the router)

I'm flatting now, and even though I am much closer to the cabnet (700m according to Chorus tech) my sync speeds barly hit 12000kb/s rather than what I expected (being the high 20000kb/s mark) I'm in a VDSL2 zone, which I assumed would be the better place to be since only people close enough to the cabnet can get VDSL2 and that ADSL 2+ would be all the better in that particular zone,is that correct?

Foregive me for my lack of understanding or use of terms, I'm a total noob to this stuff, but very interested in how it all works and what I can do to improve what I have. Here are my line stats at the flat (former state house by the way)

Line Stats:

Mode: ADSL_2plus
Traffic Type: ATM
Status:Up
Link Power State:L0
Line Coding(Trellis):   On / On
SNR Margin (0.1 dB):   129 / 160
Attenuation (0.1 dB):    90 / 41
Output Power (0.1 dBm): 0 / 128
Attainable Rate (Kbps):14344 / 992

EDIT: Had it all in a nice grid that dissapeared when I submitted the thread. :|

Am I to understand that the attenuation the router is reporting is rediculously high? And the SNR margin is destroying my sync rate? Just a note...My router is not connected to the master socket. Would that improve things at all?

Would having a dedicated ADSL socket (like at my old house) improve sync rate and line attenuation? Or would I be wasting my money and the Chrous's time getting him out?

I also read something about removing a "Bell wire" or something which apparently increases your sync rate. I'm not sure if that applies in New Zealand however.

If there is something I can do to make it better, I want to at least look in to it to see if I will gain better over-all service. I miss my 2.3MB/s. I'm at just under half that right now.

I'm also aware the problem could be totally outside my control.

Thanks guys! :)

Ragnor

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#582629 17-Feb-2012 00:07

A quick test would be to unplug every device from every phone socket then find the first/master socket after the ETP where the line comes in from the street and plug the modem in there and check what line rates you get then.

cyril7

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#582643 17-Feb-2012 07:41

Hi, your line attenuation is 9dB (its in 0.1 units) which is roughly 700m just like the Chorus guy said. I would have expected a sync rate of closer to 18Mb/s. Note that unlike other Telcos (not too sure what country home is for you) you will not get a sync rate much over 18Mb/s in NZ due to Telecom NZ's conservative noise margin.

That all said your 14.4Mb/s is not too far from 18Mb/s and I would suggest that to either have a dedicated socket (with master filter) installed or just eliminating all bar the one needed socket for your modem will probably get you closer to the 18Mb/s figure.

Cheers
Cyril

coffeebaron

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#582678 17-Feb-2012 09:04

http://www.geekzone.co.nz/forums.asp?forumid=49&topicid=96226

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Broadband troubleshooting and master filter installs.
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DravidDavid

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#582730 17-Feb-2012 11:14

cyril7: Hi, your line attenuation is 9dB (its in 0.1 units) which is roughly 700m just like the Chorus guy said. I would have expected a sync rate of closer to 18Mb/s. Note that unlike other Telcos (not too sure what country home is for you) you will not get a sync rate much over 18Mb/s in NZ due to Telecom NZ's conservative noise margin.

That all said your 14.4Mb/s is not too far from 18Mb/s and I would suggest that to either have a dedicated socket (with master filter) installed or just eliminating all bar the one needed socket for your modem will probably get you closer to the 18Mb/s figure.

Cheers
Cyril

Thanks Cyril!

I will test the master socket and look in to getting a dedicated ADSL socket with master filter. I didn't even realise the stats where in 0.1 units. I feel stupid!

Wellsford is north of Auckland. We were in a VDSL2/10Mbps zone roughly 1.8Km from the exchange. My D-Link 2740B always synced at 20 to 23Mbps with 1.3Mbps upload. This was only after interleaving was switched off though. I noticed an absolutely massive difference between sync speeds once I had Telecom switch it off for me.

Pings dropped from an average of 100ms to Telecom's Auckland servers to single didget figures.

Cheers!

cyril7

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#582734 17-Feb-2012 11:30

Hi, If you were (at home) in a VDS2 area then you would be much closer than 1.8km and at 1.8km there is no way you could achive 20Mb/s sync rate, so presumably there was a nearby cabinet.

If you only require the one socket for both phone and DSL then simply having the wiring configured so that only the one socket is lit with a direct run (even via current house wiring) back to the demarc without splits or taps to other line sections then you will achieve a similar result, but that requires you understand where all the current wiring goes and how to reconfig it.

Testing at the master socket (or first socket after the demarc) will no give the full picture unless all other house wiring is removed also, ie just a direct unsplit line from ETP/demarc to the socket being tested.

Cyril

DravidDavid

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#583148 18-Feb-2012 12:22

cyril7: Hi, If you were (at home) in a VDS2 area then you would be much closer than 1.8km and at 1.8km there is no way you could achive 20Mb/s sync rate, so presumably there was a nearby cabinet.

If you only require the one socket for both phone and DSL then simply having the wiring configured so that only the one socket is lit with a direct run (even via current house wiring) back to the demarc without splits or taps to other line sections then you will achieve a similar result, but that requires you understand where all the current wiring goes and how to reconfig it.

Testing at the master socket (or first socket after the demarc) will no give the full picture unless all other house wiring is removed also, ie just a direct unsplit line from ETP/demarc to the socket being tested.

Cyril

I don't understand house wiring enough to reconfigure anything. You were right, testing the ADSL at the main phone jack didn't change anything. Is the demarc point in or outside the house? I'm guessing ETP stands for "External Termination Point"?

I'm guessing the reason it didn't change anything is because all jacks are configured to receive an ADSL signal which is somehow causing a slow down and configuring a single dedicated jack for ADSL will prevent this from happening?

So what I gather you are saying is I need a direct line from where the telephone line connects externally to the demeric point which I'm assuming is inside the house, directly to a dedicated socket specifically for ADSL? Please correct me if I'm wrong. Trying my best to get my head around this stuff! :)

I'm going to need to call someone in to do this at some stage, but I'd like to understand it first. :)

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HowickDota

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#583159 18-Feb-2012 13:05

If it's any help, I'm about 350m from the cabinet and get 9.5db/4.7db attenuation.
Sync at 20284.

DravidDavid

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#583172 18-Feb-2012 13:29

HowickDota: If it's any help, I'm about 350m from the cabinet and get 9.5db/4.7db attenuation.
Sync at 20284.

That is the kind of sync I'd like! I'm only getting between 14000 and 15000.

Ragnor

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#583194 18-Feb-2012 14:39

So what I gather you are saying is I need a direct line from where the telephone line connects externally to the demeric point which I'm assuming is inside the house, directly to a dedicated socket specifically for ADSL? Please correct me if I'm wrong. Trying my best to get my head around this stuff! :)

Yes where the line comes into the house before any phone jacks you install a master filter/splitter. You have the incoming line go into the splitter, then coming out of the splitter you have two pairs of wires, one pair connectc to the existing wiring going to the existing phone jacks. The pair you run a new wire to where you want the dedicated phone jack for adsl to be.

The job of the master filter is to remove extra distance/attenuation added by the daisy chained internal house wiring, you can probably expect to gain at least 1-2Mbit, maybe more depending on how many jacks there are and the length and quality of the internal wiring.

DravidDavid

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#583225 18-Feb-2012 16:05

Ragnor:
The job of the master filter is to remove extra distance/attenuation added by the daisy chained internal house wiring, you can probably expect to gain at least 1-2Mbit, maybe more depending on how many jacks there are and the length and quality of the internal wiring.

Thanks! Yea, there are 3 phone jacks. If I am only to gain 1 to 2 megabits more out of it, its hardly worth calling a technician out for 300 dollars to install a dedicated ADSL jack. I guess installing a splitter and a new jack is no easy task either.

Would I benefit from a better router at all? Currently have a Dynalink RTA-1025WV6. It was provided by one of our flatmates, so I'm not sure how well they perform compared to other routers.

Ragnor

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#583335 19-Feb-2012 00:33

I helped a mate install one last month, it wasn't very tricky in his case.

The complexity depends on the house eg: where does the phone line come into the house and where are you going to want the dedicated dsl jack to go.

You can get a master filter/splitter + half a dozen cap connectors for connecting the wires for under $30 off trademe.

Mostly it depends on how confident you are with general DIY I guess. There are quite a few threads about installing a master filter/splitter if you search geekzone.

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cyril7

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#583362 19-Feb-2012 10:48

DravidDavid:
Thanks! Yea, there are 3 phone jacks. If I am only to gain 1 to 2 megabits more out of it, its hardly worth calling a technician out for 300 dollars to install a dedicated ADSL jack. I guess installing a splitter and a new jack is no easy task either.

Would I benefit from a better router at all? Currently have a Dynalink RTA-1025WV6. It was provided by one of our flatmates, so I'm not sure how well they perform compared to other routers.

Hi, as I said in my first post your current speeds are not too far from what you can expect, therefore any effort now will only achieve 2-3Mbs/s at best.

Just a point the issue with multiple outlets in the house (without a master filter) has nothing to do with the attenuation, infact that is unlikely to change dramatically from what it is, but more to do with the reflections from outlets that are not terminated that will result in sync speeds from achieving their maximum, only a master filter can fix this situation, having micro filters on each outlet will not help line stub reflections.

The other alternative, is if you can establish which is the first socket and you are not needing the other 2 sockets then disconnecting the other two sockets at the master socket so only that socket is connected will remove these reflections without the need for a master filter install, you can then plug a inline filter on the master socket to drive your modem and cordless phone basestation. However that solution may not suit you if you infact need a socket other than the main one, and it also assumes that one of the other sockets does not infact connect back at the demarc (if there is one before the first/master socket).

Cyril

DravidDavid

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#584708 21-Feb-2012 18:00

Thanks guys for all your help!

I think it is worth the effort, and if the house was my own I would give it a go, but I think I'll leave this house to the experts.

I think we are going to need to get a Chorus tech back anyway. Any hint of rain makes our internet drop out. Even when its dry it seems, it drops out temporarily.

Cheers,
David