Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: 13Xs on July 10, 2017, 11:51:17 AM

Title: Modem moved from extension to master socket - Should I ask for line reset?
Post by: 13Xs on July 10, 2017, 11:51:17 AM
Hi folks,

My BT Infinity service was activated about a month ago. It was syncing at more than 50Mbps through the master socket and about 37Mbps through the extension on day one, but the extension is where I needed it to go (next to the router and wired devices) so I plugged it in there. The speed gradually dropped to 31Mbps as more residents in my new build have had their lines activated.

I have now had a CAT5e extension fitted from the location of the master socket to the router and I've moved the modem to the master socket, but the speed gains have been fairly limited (hitting about 38Mbps after an hour of uptime). Would there be any point in asking BT for a line reset or will the connection automatically adjust itself to the maximum sustainable speed over time?

Cheers.
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: skyeci on July 10, 2017, 11:55:33 AM
Would need see some line stats first..
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: 13Xs on July 10, 2017, 12:11:58 PM
Here are the stats from the HG612 interface. Let me know if anything else is needed:
   
                                        Downstream   Upstream
Attainable rate (kbit/s)   44596           12108
SNR margin (dB)   5.9   8.1
Line attenuation (dB)   20.5   0
Output power (dBmV)   12   7.5

                            Downstream   Upstream   
Line rate (kbit/s)   39735            9999
CRC errors   0    0    0    0
FEC errors   0    5    0    0
HEC errors   0    0    0    0
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: burakkucat on July 10, 2017, 05:50:35 PM
Don't look at the GUI of the HG612, it tells lies.  :(

Please access the HG612 from the command line, either via ssh or telnet, and then gain access to the Busybox shell by a sh command. Finally invoke xdslcmd info --stats, copy the output produced and post it to this thread -- preferably between [code] ... [/code] tags.
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: 13Xs on July 11, 2017, 06:10:39 PM
I used DSLstats to grab this. It may have answered my question as the line speed has crept up by 1Mb since this time yesterday.

There do seem to be a lot of FEC errors, but I was looking at BT's DSL checker again to see what line speed I should be expecting and my line is now marked as having a bridge tap. The current line rate of 40.5Mbps is actually 0.5Mbps above the projected top end for an impacted line, so I won't bother complaining.

Code: [Select]
xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Last initialization procedure status: 0
Max: Upstream rate = 12051 Kbps, Downstream rate = 45480 Kbps
Bearer: 0, Upstream rate = 9999 Kbps, Downstream rate = 40510 Kbps

Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode(0x0)
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 5.9 8.1
Attn(dB): 20.4 0.0
Pwr(dBm): 12.1 7.4
VDSL2 framing
Bearer 0
MSGc: 18 58
B: 51 236
M: 1 1
T: 64 23
R: 12 16
S: 0.0408 0.7543
L: 12536 2694
D: 793 1
I: 64 127
N: 64 254
Counters
Bearer 0
OHF: 30867457 1601981
OHFErr: 536 56
RS: 3607005183 51838
RSCorr: 775589 62361
RSUnCorr: 5840 0

Bearer 0
HEC: 1344 0
OCD: 35 0
LCD: 35 0
Total Cells: 2014087693 0
Data Cells: 194618265 0
Drop Cells: 0
Bit Errors: 0 0

ES: 166 54
SES: 0 0
UAS: 41 41
AS: 81001

Bearer 0
INP: 3.00 0.00
INPRein: 0.00 0.00
delay: 8 0
PER: 2.62 8.70
OR: 73.16 58.79
AgR: 40583.47 10057.90

Bitswap: 51678/51678 544/544

Total time = 22 hours 30 min 42 sec
FEC: 775589 62361
CRC: 536 56
ES: 166 54
SES: 0 0
UAS: 41 41
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 15 minutes time = 42 sec
FEC: 715 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 6189 3
CRC: 0 1
ES: 0 1
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Latest 1 day time = 22 hours 30 min 42 sec
FEC: 775589 62361
CRC: 536 56
ES: 166 54
SES: 0 0
UAS: 41 41
LOS: 0 0
LOF: 0 0
LOM: 0 0
Previous 1 day time = 0 sec
FEC: 0 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
Since Link time = 22 hours 30 min 1 sec
FEC: 775589 62361
CRC: 536 56
ES: 166 54
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
LOM: 0 0
#

Edit:

And the Stats page, if it's any use:

Code: [Select]
Stats recorded 11 Jul 2017 18:33:11

DSLAM/MSAN type:        BDCM:0xa48c / v0xa48c
Modem/router firmware:  AnnexA version - A2pv6C038m.d24j
DSL mode:                VDSL2 Profile 17a
Status:                  Showtime
Uptime:                  23 hours 9 min 47 sec
Resyncs:                0 (since 11 Jul 2017 18:28:39)

Downstream Upstream
Line attenuation (dB):  20.4 0.0
Signal attenuation (dB): Not monitored
Connection speed (kbps): 40510 9999
SNR margin (dB):        5.9 8.1
Power (dBm):            12.1 7.4
Interleave depth:        793 1
INP:                    3.00 0
G.INP:                  Not enabled Not enabled
Vectoring status:        5 (VECT_UNCONFIGURED)

RSCorr/RS (%):          0.0208 1.6444
RSUnCorr/RS (%):        0.0002 0.0000
ES/hour:                10.0 0

One thing I have noticed is that my minimum pings have increased from about 5ms to 14ms over the past day or so. I've run a tracert and it shows this:

 1    <1 ms    <1 ms    <1 ms  R7800 [192.168.1.1]
  2     *        *        *     Request timed out.
  3     *        *        *     Request timed out.
  4    13 ms    13 ms    13 ms  31.55.187.184
  5    13 ms    13 ms    13 ms  core2-hu0-17-0-1.southbank.ukcore.bt.net [195.99.127.188]
[Blah blah blah]

I live about half a mile from the XXX XXX, so 13ms seems a bit high to the first hop. I'm guessing interleaving has been turned on?
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: burakkucat on July 11, 2017, 07:36:25 PM
I used DSLstats to grab this. It may have answered my question as the line speed has crept up by 1Mb since this time yesterday.

Thank you for the "--stats" output. That is the information that skyeci would like to see.  :)

Quote
. . . I was looking at BT's DSL checker again . . . my line is now marked as having a bridge tap.

Interesting. That should show up in the Hlog plot.
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: ejs on July 11, 2017, 07:47:00 PM
If you've moved the modem to the master socket, then any unfiltered extension wiring is the bridge tap. You either need to disconnect the extension telephone wiring, or filter it off at the master socket with a filtered faceplate.
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: 13Xs on July 11, 2017, 09:45:55 PM
As I've no use for the extensions, I plugged the microfilter/modem into the test socket. Is that adequate in terms of isolating the extensions?
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: burakkucat on July 11, 2017, 10:18:32 PM
Is that adequate in terms of isolating the extensions?

Yes, it should be. However it would be worthwhile checking each extension socket in turn, by plugging in a telephone, to ensure every one is now isolated. Just occasionally some "creative" wiring, from times past, will leave an extension socket connected to the circuit before the NTE5 and still "live".
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: 13Xs on July 15, 2017, 04:13:25 PM
Using the test socket and replacing the RJ11 cable with a Tandy shielded twisted pair have helped. Interleaving has been turned off, so I'm now pinging 5ms to that BT Southbank server, and my downstream rate is 45Mbps (hitting a max of 42.5Mbps through Speedtest). Seems pretty good given that the cable length is 650-700m.
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: burakkucat on July 15, 2017, 06:09:19 PM
Have you made the check to ensure that all extension sockets are now no longer live?  :-\
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: 13Xs on July 16, 2017, 02:14:45 PM
Yup, they're dead.
Title: Re: Modem moved from extension to master socket - Should I ask for line reset?
Post by: burakkucat on July 16, 2017, 04:02:43 PM
Yup, they're dead.

So now we can probably rule out a bridge tap within your own domain.