Topic: DSL-300T long line (Read 1894 times)

clewlow · « **on:** March 18, 2011, 12:22:33 PM »

Hello

New to the forum, thanks in advance for any help and hope this is not duplicated elsewhere.

I am on a fairly long line (3.6km) on ADSL Max using D-Link DSL-300T. ISP is Orange (non-LLU)
Have been trying to get the best IP profile possible on my line. I have noticed the Noise Margin dropping right down to near zero in the evenings, modem resyncs at a lower rate and IP profile reduces. Also following most recent BT SFI visit the interleaving has been taken off - not sure why? Should the interleaving be switched back on?
I have tried a couple of other routers (Livebox & DGN1000) but neither gave me a better sync rate than the D-Link. On the master socket with inbuilt filter fitted by engineer. Here are the stats from the modem (at 12 noon the noise margin seems OK but tends to drop later on)

Any suggestions gratefully received!

Thanks

AR7 DSL Modem Statistics:
--------------------------------
[DSL Modem Stats]
US Connection Rate: 448 DS Connection Rate: 4672
DS Line Attenuation: 54 DS Margin: 6
US Line Attenuation: 63 US Margin: 20
US Payload : 16826496 DS Payload: 67005648
US Superframe Cnt : 1823745 DS Superframe Cnt: 1823745
US Transmit Power : 10 DS Transmit Power: 17
LOS errors: 0 SEF errors: 0
Frame mode: 3 Max Frame mode: 0
Trained Path: 0 US Peak Cell Rate: 1056
Trained Mode: 3 Selected Mode: 3
ATUC Vendor ID: 1414747203 ATUC Revision: 1
Hybrid Selected: 1

[Upstream (TX) Interleave path]
CRC: 0 FEC: 0 NCD: 1
LCD: 0 HEC: 0

[Downstream (RX) Interleave path]
CRC: 0 FEC: 0 NCD: 0
LCD: 0 HEC: 0

[Upstream (TX) Fast path]
CRC: 22 FEC: 1190 NCD: 0
LCD: 0 HEC: 68

[Downstream (RX) Fast path]
CRC: 2196 FEC: 0 NCD: 0
LCD: 0 HEC: 0

[ATM Stats]
[Upstream/TX]
Good Cell Cnt: 350552
Idle Cell Cnt: 32408037

[Downstream/RX)]
Good Cell Cnt: 1395951
Idle Cell Cnt: 340227191
Bad Hec Cell Cnt: 2057
Overflow Dropped Cell Cnt: 0

[SAR AAL5 Stats]
Tx PDU's: 235979
Rx PDU's: 380462
Tx Total Bytes: 122163836
Rx Total Bytes: 259982786
Tx Total Error Counts: 0
Rx Total Error Counts: 60

[OAM Stats]
Near End F5 Loop Back Count: 0
Near End F4 Loop Back Count: 0
Far End F5 Loop Back Count: 0
Far End F4 Loop Back Count: 0

roseway · « **Reply #1 on:** March 18, 2011, 01:11:51 PM »

Hi and welcome,

There are some odd anomalies in those figures:

- The upstream attenuation is shown as much higher than the downstream, which is most unlikely.
- There is a figure for upstream FECs in the Fast Path section, which isn't right (FECs are associated with interleaving).

It appears that some routers don't report the interleaving status correctly, so it may possibly be that your connection is interleaved but the router is misreporting it. Certainly I would be surprised if you had been switched over to Fast Path without your asking for it, and Interleaving is almost always better on a longish line like yours.

To get the best out of your connection, it's worth going to some trouble to make sure that your own internal setup is as good as possible, and there's some advice on this here.

clewlow · « **Reply #2 on:** March 18, 2011, 01:35:10 PM »

Hi Eric

Many thanks, before the engineer visit yesterday the modem was reporting Interleaved mode. Also post-engineer, the ping time has now reduced from about 40ms to 20ms. I had asked for engineer visit due to the high CRC errors that I saw in the stats, previously these were in the interleaved section and now they appear in the fast path section. I'm already on the master socket which has an RF filter and a filtered faceplate fitted by the SFI chap yesterday.
Thanks again

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Author Topic: DSL-300T long line (Read 1894 times)

clewlow

DSL-300T long line

roseway

Re: DSL-300T long line

clewlow

Re: DSL-300T long line