Fibre Installed : Speeds not as I expected

FoolishlyWise · ‎16-02-2010

Fibre was installed at about 8:45ish this morning, install went smoothly. Hacked the modem whilst the OR engineer was at the property whilst he was crimping the cable (He didnt actually know I was doing this :L), before he left, ran a few speedtests, got 34/35meg, and with a Max sync speed of around 53meg down, 18.5 meg upload.
I was told (by someone from PN as far as I remember) that the cabinet that serves the property is around 120m away by road according to google (but OR guy said about 60m). Isnt the attainable rate a little low if the cabinets around 120m away? (Even if it took a non-straight route, it cant stem out more than 200m).
Could it be that the cabinet is actually an ECI-based cab, and ive been given a Huawei modem? (I vaguely remember reading all Phase 6 cabs would be ECI on a Openreach PDF). - Or could it be the line is still in 10 day training mode?
I raised a ticket expressing interest in the 80/20 trial too, going to see how that goes aswell.
Any help would be awesomeness
Cheers

w23 · ‎08-01-2008

At 120m you'd expect 'full whack' (even on 80Mb/s) but this assumes that the cable length is something like the distance measured, not sure if aluminium cable would make that much difference, normally 300m of decent copper will give close to 80Mb/s.
Is the FTTC cab close to the old cab (you need to add the distance between the cabs)?
Can you get the Attenuation table out of the modem?
AFAIK Huawei modems perform perfectly well on ECI cabs.
There's a lot of info on the ThinkBroadband forums regarding speeds, distances, attenuation etc. Also worth searching for posts by 'Bald_Eagle1' who has produced some excellent graphing scripts for this modem.

Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
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FoolishlyWise · ‎16-02-2010

Ah knowing my luck, it may well be aluminium. How can you check this out of interest? (Is it a case of opening up the master socket, checking the A&B connections to see if their copper or aluminium (looking at the colour?)
Old cab i think is around 75cm away from the new one, so 120.75m. Stats page is attached, im trying to get the Line Attenuation values via Telnet but i have no clue how!

w23 · ‎08-01-2008

To get the attenuation figures you need to telnet into the modem, I'll try to find the specific commands (can't remember right now)

[Edit] Memory's still a bit hazy, once you log in using telnet I think you need to type sh, once you're in the specific command is xdslcmd info --pbParams
Here's an example: http://community.plus.net/forum/index.php/topic,105351.msg898997.html#msg898997

Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.

FoolishlyWise · ‎16-02-2010

I have a feeling this looks bad somehow:
# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 18545 Kbps, Downstream rate = 55348 Kbps
Path: 0, Upstream rate = 1999 Kbps, Downstream rate = 39998 Kbps
Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3959)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3959)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 18545 kbps 55348 kbps
Actual Aggregate Tx Power: 2.7 dBm 13.1 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 4.4 24.0 36.2 N/A 12.0 29.9 46.4
Signal Attenuation(dB): 7.1 23.0 34.2 N/A 12.0 29.9 46.4
SNR Margin(dB): 20.5 20.4 20.3 N/A 10.8 10.8 11.0
TX Power(dBm): -4.3 -19.9 1.6 N/A 10.3 7.8 5.9
EDIT: Have a look at the map for an illustration of where the telegraph pole and line enters the house to where the fibre cab is. Was told on this thread: http://community.plus.net/forum/?topic=99554.msg843559 that the cab is the one down on the junction of Essex Road.

chrispurvey · ‎13-07-2012

Hi Meh,
Your profile is 40MB/s D/L and 2MB/s U/L, so 34/35MB/s is acceptable, although your achievable speeds on your line are both higher on the D/L and U/L than you are currently getting. Your profile is not set up for these speeds, however when you have moved over to the 80/20 trial then you will see the speed increase on your connection to your attainable speeds, possibly faster.
Your modem is showing you your attainable rate what it is at the moment, but the only way we will know if your going to achieve faster than the attainable rate is when you are on the 80/20 trial. Certainly the quality and route of the line can also have a bearing on your attainable speed.
Chris

FoolishlyWise · ‎16-02-2010

Yep, currentley waiting to go onto the 80/20 trial, modems on Profile 17a, Ticket ID 57732406 has the request. The attenuation seems worrying, does this change over the 10day period?
Is there any way of checking if the line is alumium or copper? (Without taking the master socket apart and finding the dropwire?)
dial tones always been clear and the line going from the house to the pole is in quite good condition, and according to the engineer, the line apparentley takes a direct route from the telegraph pole (which is right outside the property) to the cab.

w23 · ‎08-01-2008

These figures are from someone who recons they're about 600m:

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 16395 Kbps, Downstream rate = 46760 Kbps
Path: 0, Upstream rate = 16428 Kbps, Downstream rate = 48511 Kbps
Discovery Phase (Initial) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3959)
Medley Phase (Final) Band Plan
US: (0,95) (868,1207) (1972,2783)
DS: (32,859) (1216,1963) (2792,3959)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 16395 kbps 46760 kbps
Actual Aggregate Tx Power: 6.8 dBm 12.7 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 5.4 29.7 44.9 N/A 14.5 36.4 56.3
Signal Attenuation(dB): 7.2 28.9 43.8 N/A 14.5 36.4 56.3
SNR Margin(dB): 6.0 6.2 6.2 N/A 5.3 5.3 5.4
TX Power(dBm): -4.1 -13.1 6.3 N/A 9.8 7.8 5.1

So I'd possibly question either your line length or quality, I'd certinly recomend having a look here: http://forum.kitz.co.uk/index.php/topic,10552.0.html

Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.

chrispurvey · ‎13-07-2012

Everything seems to be going through regarding the fibre trial. There is no definitive way to say if your line is copper or aluminium.
I'd just leave your line alone for the moment and monitor it to see what it becomes stable at.

Word_Warrior · ‎30-07-2007

The way I understand it is that you could have Aluminium from the cab to the junction that serves your house and copper or Aluminium after that. If your house was built in the 70's then there is a good chance it was Aluminium due to a copper shortage at that time.
I've even got Stainless steel plumbing!!!

Anotherone · ‎31-08-2007

I'm thoroughly confused (not being any expert on Fibre) but the stats.png attached to reply #2 shows Line Rate 39998 downstream and 1999 upstream,so what's the problem? Even if it was a tortuous 200m to the cab I wouldn't expect Aluminium cable to affect it at all. Also there would be no point in looking at the back of the NTE, the cable entering the house will be copper whether it be overhead or from a Connection box outside if underground.
Edit: Oh, and the attenuation is 0dB, so you wouldn't get any better if the cab was in your front garden!

FoolishlyWise · ‎16-02-2010

@Anotherone, im on about Max Attainable, ie: what id get on 80/20. Still, the 34meg is like 10 times what I used to get.
And the 0db attenuation: Its a bug in the UI, not the real value! The real line attenuations in the code thingybob I posted before.

Anotherone · ‎31-08-2007

Ah, right. Thanks for the explanation, I'm on a steep learning curve here. Now why would BT supply equipment with bugs in

Out of curiosity what did the BT speedtester give for the Upload speed?
This page has some interesting info. At 200m estimated max. is 65Mb/s

w23 · ‎08-01-2008

The speed estimates there seem to be 'worst case' (assuming maximum cross-talk). My line syncs at 62 odd Mb/s and I know I'm a good 450m cable run to the cab (the FTTC cab is actually just over 320m but the PCP is a good 60m+ further up the road so the signal has to travel from the FTTC cab away from my house (back toward the exchange!) a good 60m then another 60m+ back again before it's gone anywhere then there's a bit to allow in and out of the cabinets and whatever it does under the manhole covers).

Call me 'w23'
At any given moment in the universe many things happen. Coincidence is a matter of how close these events are in space, time and relationship.
Opinions expressed in forum posts are those of the poster, others may have different views.

Anotherone · ‎31-08-2007

I don't think I'd believe any of the modem's max speed figures if the modems have buggy firmware. Especially as in the example in reply #7 the max. speeds are slower that the actual speeds!

Fibre Installed : Speeds not as I expected

Fibre Installed : Speeds not as I expected

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Re: Fibre Installed : Speeds not as I expected