Topic: Half Speed (Read 7887 times)

J0SH · « **on:** November 22, 2012, 05:59:14 PM »

Hey guys,

After waiting 3 weeks from the point of installation (FTTC) to work, we've discovered that the connection is only giving half of what it states in the router.

The router shows 70Mbit/s down and 20Mbit/s up, yet speed tests show results from 14Mbit/s to 51Mbit/s.

When I look at the line stats, it would seem the line should be able to cope with 79999Mbit/s.

A guy who lives over the road and is on the same post and cab had his installed after a problem at the cab was fixed and is reporting speed test results of 75Mbit/s. :-o

I'll post the line stats below.

# xdslcmd info --stats
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 29639 Kbps, Downstream rate = 87076 Kbps
Path: 0, Upstream rate = 20000 Kbps, Downstream rate = 70262 Kbps

Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 6.4 12.2
Attn(dB): 0.0 0.0
Pwr(dBm): 12.8 6.1
VDSL2 framing
Path 0
B: 45 236
M: 1 1
T: 64 5
R: 14 16
S: 0.0208 0.3771
L: 23040 5410
D: 1651 1
I: 60 255
N: 60 255
Counters
Path 0
OHF: 27211697 468687
OHFErr: 368 3
RS: 2671226720 4109423
RSCorr: 2187451 12
RSUnCorr: 14935 0

Path 0
HEC: 3712 0
OCD: 0 0
LCD: 0 0
Total Cells: 624345669 0
Data Cells: 24200373 0
Drop Cells: 0
Bit Errors: 0 0

ES: 29 3
SES: 0 0
UAS: 22 22
AS: 36426

Path 0
INP: 4.00 0.00
PER: 1.33 6.12
delay: 9.00 0.00
OR: 120.00 203.67

Bitswap: 7664 4

Total time = 10 hours 7 min 29 sec
FEC: 2187451 12
CRC: 368 3
ES: 29 3
SES: 0 0
UAS: 22 22
LOS: 0 0
LOF: 0 0
Latest 15 minutes time = 7 min 29 sec
FEC: 18344 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 97717 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 10 hours 7 min 29 sec
FEC: 2187451 12
CRC: 368 3
ES: 29 3
SES: 0 0
UAS: 22 22
LOS: 0 0
LOF: 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
Since Link time = 10 hours 7 min 5 sec
FEC: 2187451 12
CRC: 368 3
ES: 29 3
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
#

# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 29663 Kbps, Downstream rate = 87076 Kbps
Path: 0, Upstream rate = 20000 Kbps, Downstream rate = 70262 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083)
Medley Phase (Final) Band Plan
US: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 29663 kbps 87076 kbps
Actual Aggregate Tx Power: 6.1 dBm 12.8 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 0.4 19.8 30.3 N/A 11.0 25.7 41.3

Signal Attenuation(dB): 0.4 19.6 30.2 N/A 11.0 25.7 41.3

SNR Margin(dB): 13.0 13.2 11.9 N/A 6.4 6.3 6.4

TX Power(dBm): -5.0 -25.8 5.7 N/A 8.8 7.3 7.4

Ixel · « **Reply #1 on:** November 22, 2012, 06:15:25 PM »

Those line statistics look similar to mine.

I've noticed by the discovery tones that you're on an ECI type cabinet, not a Huawei, although you're using a Huawei modem and not an ECI modem. Using the ECI modem performs better in regards to reducing or turning off interleaving compared to using a non-ECI modem (e.g. Huawei, Fritz!Box). Apparently some incompatibility causes small and regular errors to appear on the line which eventually can result in DLM increasing interleaving depth, delay and INP. The result of increased INP causes a reduction in sync speed as it uses it as a buffer, and also causes a small increase in the ping (from a typical 9ms to bbc.co.uk to perhaps 20ms+, at least in most cases I've come across and from my own experience). So what I'm saying is you'd probably find interleaving would get reduced considerably, or turned off even (fastpath) if you used an ECI modem. They can be easily found on eBay usually, in their unlocked or locked state.

Incase someone comes along asking me for proof, here it is:
- http://beusergroup.co.uk/technotes/index.php?title=Diary_of_an_FTTC_Install#Interesting_Notes
- http://talktalkmembers.net/forums/showthread.php?t=88701

Are you connected wirelessly or wired?
Any third party firewall software?
BT Netprotect (or whatever it's called) installed?
Have you tried restarting the router (not the modem)? If you're on BT Infinity there's an IP profile that only updates when a new PPP session is made.

Those are my initial ideas, I'm sure others will reply shortly with some more ideas. Apart from that, your statistics appear to be fine in my view, well, as I say they're similar to mine.

J0SH · « **Reply #2 on:** November 22, 2012, 07:10:41 PM »

Hey,

Thanks for the excellent reply.

I've just been over to the guy who is on BT and looked at his modem. He has been supplied with an ECI modem. He isn't using his at the moment due to his computers being infected, so has allowed me to borrow it for the time being.

The router is now showing 73.3Mbit/s connection rather than the 70.2Mbit/s.

Speed tests seem to be similar at the moment.

I wonder how difficult it will be to get hold of an ECI modem rather than the one we have.

The ECI modem seems to have round lights on it and also seems thicker.

Ixel · « **Reply #3 on:** November 22, 2012, 07:30:32 PM »

Yeah, the ECI modem is thicker and has slightly different lights and coloured ports on the back, it also runs cooler compared to the Huawei modem. You can, at the time of posting, find a locked ECI modem on eBay by simply searching for 'ECI modem'. There were unlocked ones not long ago on there.

Unfortunately somewhere in Openreach a person or group of people had the infinite wisdom earlier this year of deciding not to restrict the type of modem supplied on installation to a customer, e.g. ECI modem if the cabinet is ECI, or Huawei modem if the cabinet is Huawei. Originally this was restricted for complete compatibility between modem and street cabinet hardware. If left alone for a few days without connection disruption, and assuming you don't have a bad line, DLM should start to reduce the level of interleaving hopefully which will result in your sync speed going up. Personally I'd advise restarting the router (not modem) every couple of days to ensure your IP profile updates with your current modem sync speed (assuming your on BT Infinity).

Also can you answer the previous questions about how you are connected to the router (e.g. wirelessly or wired), etc.?

J0SH · « **Reply #4 on:** November 22, 2012, 07:41:10 PM »

Thanks for the reply.

We are on Sky FTTC so it would be a case of having to restart the modem to get the new sync speeds... :-(

I am using a wired connection for all of these tests. I even disable the wireless whilst I do these tests.

Just tested to BT Speed test and it is still showing 45-47Mbit/s despite the 73.32Mbit/s sync on the router/modem.

I don't know whether I'll be able to borrow this for that long, so I will order one of these ECI modems from eBay this evening. When that arrives, I shall leave it connected for 36 hours or so and see whether the pings reduce.

It is annoying that our connection was on and off (well the modem was) during the time we had no connection. The three weeks of no connection probably hasn't helped with things. You would have thought that they'd have reset the DLM because of this...

Ixel · « **Reply #5 on:** November 22, 2012, 08:03:57 PM »

I see, well I'm sure someone else will come up with some ideas as to what might be causing the slow throughput. I presume you've tried speedtest.net? Sometimes the BT one can produce lower than expected results.

Regarding DLM profile reset, yes I'm a BT Business Infinity customer (purely for static IP's and UK support) but despite having a recent battery contact fault (now resolved) and the fact that my line can support more than the speed I'm capped at currently unfortunately I couldn't get them to reset the DLM profile. As far as they're concerned they said my line was achieving the minimum expected from their estimate (58.5Mbps down, I'm getting 60Mbps currently, the line can do around 93Mbps so would do the full 80Mbps no problem, I also have no interleaving, just a cap).

Whatever you do though, avoid restarting or disconnecting and reconnecting the modem. Do this on the router itself by all means as DLM won't perceive that as a possible line fault. If DLM is due to give your line an award for good stability then it will usually do so early in the morning between 3am-6am, and when it does it will automatically cause your modem to re-sync at the new profile configuration that DLM has applied.

J0SH · « **Reply #6 on:** November 22, 2012, 08:23:29 PM »

That's the latest test.

As I can't keep this modem, I shall have to reboot the connection on the old modem for the time being and return this one to our neighbour...

Does it get stuck on a profile and then it never raises it above that?

Our line speed was estimated at 65.5Mbit/s, so we should get more than what we're getting.

The fact that your line is able to support a faster connection and it not being able to run at that speed seems ridiculous.

What speed did your connection run at before the fault?

J0SH · « **Reply #7 on:** November 22, 2012, 08:31:56 PM »

May as well be on their 40/10 package. lol

J0SH · « **Reply #8 on:** November 22, 2012, 08:54:09 PM »

Since reconnecting the original modem, we're not on 29-38MBit/s... lol

This is a bit of a joke now. I guess it's my own fault. Probably be stuck on this profile indefinitely.

J0SH · « **Reply #9 on:** November 23, 2012, 07:41:33 PM »

One quick question... How does one identify whether their cab is ECI or not?

Ixel · « **Reply #10 on:** November 23, 2012, 08:15:19 PM »

Quote from: J0SH on November 23, 2012, 07:41:33 PM

One quick question... How does one identify whether their cab is ECI or not?

By the discovery tones given on the HG612 stats, more specifically the final tone on the third DS band.

4083 for ECI, 3959 for Huawei.

Bald_Eagle1 · « **Reply #11 on:** November 23, 2012, 08:43:25 PM »

There is also this way:-

BusyBox v1.9.1 (2010-10-15 17:59:06 CST) built-in shell (ash)
Enter 'help' for a list of built-in commands.

# xdslcmd info --vendor
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 5297 Kbps, Downstream rate = 33080 Kbps
Path: 0, Upstream rate = 5279 Kbps, Downstream rate = 28043 Kbps

ChipSet Vendor Id: BDCM:0xa39d
ChipSet VersionNumber: 0xa39d
ChipSet SerialNumber:

BDCM:0xa39d means it is Broadcom (Huawei).
I can't recall what it is for ECI, probably something like IFTN (for Infineon).

Bald_Eagle1 · « **Reply #12 on:** November 23, 2012, 08:58:10 PM »

Quote from: J0SH on November 22, 2012, 05:59:14 PM

When I look at the line stats, it would seem the line should be able to cope with 79999Mbit/s.

It might do if these stats were better:-

D: 1651 1

INP: 4.00 0.00

delay: 9.00 0.00

D: = Interleaving depth. VDSL2 has much higher values than ADSL connections, but a DS depth of 1651 looks quite high.
Mine runs at around 400 & it's quite a poor connection, not even able to achieve 40Mb due to being a long distance from the cabinet.

INP: = Impulse Noise Protection.
This is usually turned on with Interleaving & zero value when Interleaving is OFF (i.e. a value of 1).
Mine is 3.00

delay: = delay (ping times).
Mine has a value of 8.00

Your stats suggest that DLM has seen a "noisy" connection, probably with spikes of Impulse noises & it has restricted speed to provide increased stability.

Just a thought, have you conducted speed tests at very quiet times, e.g. when most sensible people are fast asleep in bed?
It may just be that you are suffering high contention with many users sharing the available bandwidth (maybe even maxing out their connections by furiously downloading films etc.)

J0SH · « **Reply #13 on:** November 23, 2012, 11:03:25 PM »

Today's line stats.

It would seem that the interleaving has reduced a little but the delay and INP are set as the same.

It would also appear that it is ECI kit in the cab. I wonder whether the new ECI modem I've ordered will help with the connection? Going to just leave things switched on 24/7 and not do any more reboots and see what happens to the stats.

# xdslcmd info --vendor
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 29246 Kbps, Downstream rate = 88624 Kbps
Path: 0, Upstream rate = 20000 Kbps, Downstream rate = 70452 Kbps

ChipSet Vendor Id: IFTN:0xb203
ChipSet VersionNumber: 0xb203
ChipSet SerialNumber: 5501843090

Link Power State: L0
Mode: VDSL2 Annex B
VDSL2 Profile: Profile 17a
TPS-TC: PTM Mode
Trellis: U:ON /D:ON
Line Status: No Defect
Training Status: Showtime
Down Up
SNR (dB): 6.3 12.5
Attn(dB): 0.0 0.0
Pwr(dBm): 12.7 6.8
VDSL2 framing
Path 0
B: 47 236
M: 1 1
T: 64 5
R: 16 16
S: 0.0217 0.3771
L: 23622 5410
D: 1549 1
I: 64 255
N: 64 255
Counters
Path 0
OHF: 26097219 455627
OHFErr: 169 0
RS: 2385920379 3260916
RSCorr: 2487032 5
RSUnCorr: 8952 0

Path 0
HEC: 2118 0
OCD: 0 0
LCD: 0 0
Total Cells: 626745634 0
Data Cells: 137835705 0
Drop Cells: 0
Bit Errors: 0 0

ES: 31 0
SES: 0 0
UAS: 22 22
AS: 36345

Path 0
INP: 4.00 0.00
PER: 1.38 6.12
delay: 9.00 0.00
OR: 138.41 203.67

Bitswap: 9432 22

Total time = 10 hours 6 min 8 sec
FEC: 2487032 5
CRC: 169 0
ES: 31 0
SES: 0 0
UAS: 22 22
LOS: 0 0
LOF: 0 0
Latest 15 minutes time = 6 min 8 sec
FEC: 2869 0
CRC: 0 0
ES: 0 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Previous 15 minutes time = 15 min 0 sec
FEC: 722287 0
CRC: 18 0
ES: 3 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
Latest 1 day time = 10 hours 6 min 8 sec
FEC: 2487032 5
CRC: 169 0
ES: 31 0
SES: 0 0
UAS: 22 22
LOS: 0 0
LOF: 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
Since Link time = 10 hours 5 min 45 sec
FEC: 2487032 5
CRC: 169 0
ES: 31 0
SES: 0 0
UAS: 0 0
LOS: 0 0
LOF: 0 0
# xdslcmd info --pbParams
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 0
Max: Upstream rate = 29264 Kbps, Downstream rate = 88624 Kbps
Path: 0, Upstream rate = 20000 Kbps, Downstream rate = 70452 Kbps

Discovery Phase (Initial) Band Plan
US: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083)
Medley Phase (Final) Band Plan
US: (0,95) (880,1195) (1984,2771)
DS: (32,859) (1216,1959) (2792,4083)
VDSL Port Details Upstream Downstream
Attainable Net Data Rate: 29264 kbps 88624 kbps
Actual Aggregate Tx Power: 6.8 dBm 12.7 dBm
============================================================================
VDSL Band Status U0 U1 U2 U3 D1 D2 D3
Line Attenuation(dB): 0.4 19.6 29.8 N/A 11.0 25.3 40.6

Signal Attenuation(dB): 0.4 19.4 29.7 N/A 11.0 25.3 40.6

SNR Margin(dB): 12.3 13.4 12.2 N/A 6.4 6.3 6.3

TX Power(dBm): -4.3 -26.0 6.4 N/A 8.6 7.4 7.4

Chrysalis · « **Reply #14 on:** December 23, 2012, 02:01:18 AM »

Quote from: Bald_Eagle1 on November 23, 2012, 08:43:25 PM

There is also this way:-

BusyBox v1.9.1 (2010-10-15 17:59:06 CST) built-in shell (ash)
Enter 'help' for a list of built-in commands.

# xdslcmd info --vendor
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 2
Max: Upstream rate = 5297 Kbps, Downstream rate = 33080 Kbps
Path: 0, Upstream rate = 5279 Kbps, Downstream rate = 28043 Kbps

ChipSet Vendor Id: BDCM:0xa39d
ChipSet VersionNumber: 0xa39d
ChipSet SerialNumber:

BDCM:0xa39d means it is Broadcom (Huawei).
I can't recall what it is for ECI, probably something like IFTN (for Infineon).

thanks for this, it seems I have a hg modem on a ECI dslam.

Code: [Select]

# xdslcmd info --vendor
xdslcmd: ADSL driver and PHY status
Status: Showtime
Retrain Reason: 1
Max:    Upstream rate = 23915 Kbps, Downstream rate = 72696 Kbps
Path:   0, Upstream rate = 20000 Kbps, Downstream rate = 71292 Kbps

ChipSet Vendor Id:      IFTN:0xb203
ChipSet VersionNumber:  0xb203
ChipSet SerialNumber:   5501843597

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Author Topic: Half Speed (Read 7887 times)

J0SH

Half Speed

Ixel

Re: Half Speed

J0SH

Re: Half Speed

Ixel

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J0SH

Re: Half Speed

Ixel

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J0SH

Re: Half Speed

J0SH

Re: Half Speed

J0SH

Re: Half Speed

J0SH

Re: Half Speed

Ixel

Re: Half Speed

Bald_Eagle1

Re: Half Speed

Bald_Eagle1

Re: Half Speed

J0SH

Re: Half Speed

Chrysalis

Re: Half Speed