G.INP on long lines to fibre

I have read recently that G.INP has been added to help improve fibre connections

Firstly is there a speed improvement?

Secondly my cabinet has only been activated in the last few days. Can I assume that G.INP will available on this cabinet.

I am currently on ADSL+ LLU and am wondering if upgrading to fibre will be worth the extra cost.

How far are you from the cabinet and what does the checker result say?

G.INP is not some kind of 'turbo' feature. It's just one of the mechanisms that FTTC DLM can use to deal with noisy lines. If your line is noisy then G.INP is a better solution than interleaving or cutting the connection speed. G.INP doesn't increase speed really - it just avoids the speed having to be reduced.

What it comes down to is that if you don't currently have fibre there's no need to concern yourself with G.INP. It shouldn't affect your decision whether to upgrade or not and it's entirely possible your line may not need it anyway.

Edited by Andrue (Sat 19-Sep-15 22:08:57)

In reply to a post by gdavid:

I have read recently that G.INP has been added to help improve fibre connections

Firstly is there a speed improvement?

Secondly my cabinet has only been activated in the last few days. Can I assume that G.INP will available on this cabinet.

I am currently on ADSL+ LLU and am wondering if upgrading to fibre will be worth the extra cost.

Depends on which cabinet you also have, if it Hauwei, then G.INP will become active, if you on a ECI cabinet then G.INP isn't availble yet.

Check at https://www.dslchecker.bt.com/ to see what speed you can get.

Edited by Nightglow (Sat 19-Sep-15 23:15:55)

The only increase in speed that you get from g.inp is where interleaving is taken off. THat can steal several mbps. It doesn't increase the basic speed the line is capable of bu, perhaps, makes it a bit more likely that it can be achieved and remain stable.

Thanks for all the replies.

The DSLChecker is not up to date. Only BT are showing that fibre is available and quoting 6 to 10 Mb/s, but being an LLU line cannot be exact.

I am on the Midhurst, Sussex exchange and cabinet 6. Don't know how to check the equipment in it. I am 1.38Km from the cabinet and is all copper.

Speed test
http://www.thinkbroadband.com/speedtest/results.html...

The router specs are as follows:-
These of course are back to the exchange.

Status
xDSL
xDSL
Mode ADSL_G.dmt
Traffic Type ATM
Status Up
Link Power State L0
Downstream Upstream
Line Coding (Trellis) On On
SNR Margin (dB) 5.3 12.0
Attenuation (dB) 59.0 31.5
Output Power (dBm) 17.1 12.5
Attainable Rate (Kbps) 2708 624
Rate (Kbps) 2432 480
K (number of bytes in DMT frame) 77 16
R (number of check bytes in RS code word) 8 8
S (RS code word size in DMT frame) 2.00 2.00
D (interleaver depth) 32 2
Delay (msec) 16.00 4.00
INP (DMT symbol) 0.79 0.04
Super Frames 37738818 37738818
Super Frame Errors 13659 1438
RS Words 1283119779 320781551
RS Correctable Errors 1172142 2020
RS Uncorrectable Errors 201064 0
HEC Errors 109056 900
OCD Errors 173 0
LCD Errors 173 0
Total Cells 3679632320 0
Data Cells 207311861 0
Bit Errors 0 0
Total ES 3642 0
Total SES 98 0
Total UAS 26 26

Edited by deleted (Sun 20-Sep-15 14:49:55)

If you have found the cabinet, pictures here.

LLU makes no difference to connection speed on FTTC. It's strange that the DSL checker isn't up-to-date. Did you use the full address option? Where and how did you get the BT estimate?

Edited by RobertoS (Sun 20-Sep-15 15:30:48)

I think the OP means he can't do the telephone number check because he's currently on LLU, so assume he did an address check (as opposed to postcode check - the postcode check doesn't show the cabinet always).

Edited by mlp (Sun 20-Sep-15 16:02:40)

Cab6 on midhurst is Huawei, so capable of G.INP - cab was enabled 21st August, so other providers should have the information. Not sure, but because of the low predicted speed, some providers might not allow you to order FTTC (don't quote me on that, probably OK with BT or plus net)

Thanks - I found the details here

http://www.dslchecker.bt.com/pls/adsl/ADSLChecker.Ad...

I'll have a look at the cabinet tomorrow when I drive by it.

Thanks - correct

He didn't say it didn't work. He said it wasn't up-to-date. So I was suspecting he used the Postcode checker, which we agree is unsafe.

However he said the BT checker gave him a figure. Given that he doesn't have a usable phone number, my question was which BT checker and what info did he supply to it.

You can't just copy the URL, as that doesn't link to your results. You have to copy and paste the table, including the line above it, (with the address edited out).

Thanks for the info.

TalkTalk are at the exchange. Does that mean that they will be able to offer Fibre?

I did hear that TT were going offer their fibre to wholesale so that other providers can resell it. Any knowledge of this?

Doesn't give any useful info at the moment but this from BT retail


Yes! You can get Unlimited Faster Broadband
FASTER BROADBAND
You could get
6Mb - 11Mb Estimated download speed range*
See standard BT Broadband speeds
Less about these estimated speeds

You just posted

In reply to a post by gdavid:

Thanks - I found the details here

http://www.dslchecker.bt.com/pls/adsl/ADSLChecker.Ad...

I'll have a look at the cabinet tomorrow when I drive by it.

Now you say it doesn't give any useful information.

This "Unlimited faster broadband" from BT Retail, what did you give it? Postcode, or full address?

I'm trying to help you, but you keep coming back with contradictory answers.

I don't think it has ever happened before that the checker above has been out of date, so somewhere things don't add up.

Please can you copy and paste the table it gives for your address, including the line ovove, with the address edited out.

If you are using just postcode the BT Wholesale checker can be wrong, but if you use Postcode + House then the BT Wholesale checker should be correct.

Picking a postcode and address on cabinet 6 that is over 1km from the cabinet I got the following:

Address XXX PETERSFIELD, GU31 5XX on Exchange MIDHURST is served by Cabinet 6
Featured Products
High Low High Low
FTTC Range A (Clean) 20 13.1 1.2 0.8 -- Available
FTTC Range B (Impacted) 15.1 5.4 1.2 0.6 -- Available

Sorry - I misread the site

Featured Products


Downstream Line Rate(Mbps)


Upstream Line Rate(Mbps)


Downstream Range(Mbps)


Availability Date
High Low High Low
FTTC Range A (Clean) 10.5 5.8 1.2 0.8 -- Available
FTTC Range B (Impacted) 8 2.7 1.2 0.5 -- Available
WBC ADSL 2+ Up to 1 -- 1 to 3.5 Available
ADSL Max Up to 1 -- 0.75 to 2.5 Available
WBC Fixed Rate 0.5 -- -- Available
Fixed Rate 0.5 -- -- Available
Other Offerings
Fibre Multicast -- -- -- Available
Copper Multicast -- -- -- Available

Thanks - I was using postcode and identified the correct address