FEC errors ?

i used to be syncing at 7648 with an ip profile of 6500 and snr of 6.

for weeks my internet has felt unresponsive and slow at times , (but on speed test always getting just over 6mb), have had an BT OR engineer out, and he says the reason for this , is i am getting 100s of FEC errors a second, was showing on his equipment when he tested at the cabinet and just outside my property.

He was he nearly 8 hours but everything he checked was fine, he think the FEC errors is been caused by REIN, in the mean time he has had my snr set at 9 , sync at 5984 with ip profile of 5000 , with only a couple of FEC errors a second.

At the moment everything seems more quicker , and more responsive, will this be due to the above ?

Is it likely the FEC errors are been caused by REIN ?

Edited by deleted (Sun 12-Apr-15 19:24:34)

Is it likely the FEC errors are been caused by REIN ?

Not always, but if he spent 8 hours on site, and he was still seeing them, there is a fair chance. Did the engineer get a REIN case raised ? Are any of your immediate neighbours having similar issues ?

If it were REIN, I'd be dubious that having the target snd hard pinned at 9db would really be masking the issue so well.

Are you are to post stats from your router ?

You have interleaving on your line? Its common to see FEC errors on a line with interleaving turned on anyway

My neighbours don't seem to be having an issue

I have a REIN engineer coming later in the week

i have interleaving on my line

here are current stats, many thanks

Uptime: 2 days, 16:17:31

DSL Type: ITU-T G.992.1

Bandwidth (Up/Down) [kbps/kbps]: 448 / 5.984

Data Transferred (Sent/Received) [GB/GB]: 0,98 / 1,99

Output Power (Up/Down) [dBm]: 12,3 / 19,9

Line Attenuation (Up/Down) [dB]: 22,5 / 37,5

SN Margin (Up/Down) [dB]: 26,0 / 9,6

System Vendor ID (Local/Remote): TMMB / ----

Chipset Vendor ID (Local/Remote): BDCM / TSTC

Loss of Framing (Local/Remote): 64 / -

Loss of Signal (Local/Remote): 10 / -

Loss of Power (Local/Remote): 0 / -

Loss of Link (Remote): -

Error Seconds (Local/Remote): 1.647 / -

FEC Errors (Up/Down): 1 / 118.272

CRC Errors (Up/Down): 0 / 44

HEC Errors (Up/Down): - / 44 / 382

FEC errors should be expected when interleaving is enabled but too many can be detrimental to performance.

Before the engineer came, was the performance degraded all of the time or only at specific times of the day? If so what times?

The latter is usually a sign of REIN (Although in rare cases it can be continuous) whereas the former can be a sign of a faulty connection somewhere.

There's a useful article on REIN (and how to detect it) here. All you need to detect REIN interference generated in the home is an AM radio tuned to 612kHz.

All you need to detect REIN interference generated in the home is an AM radio tuned to 612kHz.

Yes, but lots of things make an audible noise on a radio and yet are not causing any interference.

Well, I'm going to give it a shot. It may be the cat. You never know.

Then cut its whiskers off.

You tried to do a ping test or similar to see if its packetloss? Not sure if speedtests really pickup any packetloss when showing you your download speeds, but you would certainly notice it when browsing

In reply to a post by Zarjaz:

All you need to detect REIN interference generated in the home is an AM radio tuned to 612kHz.

Yes, but lots of things make an audible noise on a radio and yet are not causing any interference.

An AM radio used as described will help you to identify possible culprits. By switching them off, you may be able to identify the actual culprit(s). Of course, it will be of no use if the cause of interference is the house wiring itself or is outside the house.

How close to the wires would interference have to be to cause an impact on your connection?

If there's noise(s) present on the radio within the property, start by switching off the main fuse board. If it goes, all ancillary switches off, main switch back on, and put them back on one at a time till you've localised it. The individual trips are often labelled, so this can narrow it down too.

Depends how strong the source is, and how it's broadcast.

In reply to a post by bobble_bob:

How close to the wires would interference have to be to cause an impact on your connection?

I've never tried it so I can only say 'watch the video'. Anyway, it would be governed by the strength of the emissions and how much the internal cabling acts as an antenna. For the trick to work, the output from an appliance would have to be pretty gross (in the video, a power brick). One common error is to place the modem too close to a TV set.

Look what I just found on Ebay, a tad expensive, but the ideal companion for your tranny when hunting REIN.

I can imagine all the OpenReach engineers flogging theirs and using their granny's radio.

Funny you say that ......... I do use my Nan's old Roberts.

Use the radio to hone in, and the 444 to say, yep, that's kicking out enough RF in the right frequency to cause the fault.

I thought I recognised those as Speedtouch stats.

Here is what the old Be stats analysis has to say...

http://be.nfshost.com/

Expected download speed at your current sync rate: 636.59 KB per second (or 5093 kbit)

Expected upload speed at your current sync rate: 47.66 KB per second (or 381 kbit)

Problem: Downstream sync speed of 5984 kbit is 3549 kbit slower or 63 percent of the average for connections with the same downstream attenuation of 37.5dB.

Problem: Output power down (19.9dBm) is very high. Most common values are 17 to 19.5dBm.

Problem: Signal Noise Margin Down (9.5dB) is extremely high. Be* may have put you on this profile to compensate for a high error rate. If you know that your line is actually reliable, lowering the value to the average of 6dB should give a sync speed increase. Call Be* to change it (3dB steps only).

Problem: Signal Noise Margin Up (26dB) is higher than average and may be this high in order to compensate for current/previous high error rates.

Problem: There are some FEC Up errors. FEC errors are *corrected* errors, so these are probably nothing to worry about. Speedtouch routers have a habit of misreporting FEC errors anyway.

The usual cause of noise pickup is a non isolated ringwire - have you taken any steps to ensure you dont have one? Do you even know what it means?

If the "engineer" just looked at your router stats he may well have been mislead as I've seen Tomson/Speedtouch routers report many millions of FEC errors over a day.

Boosting the target noise margin may have fixed some CRC errors that were giving you grief but the real fix is to eliminate noise pickup. As your neighbours have no isues that suggests it is in your house and probably picked up by a ringwire.

Expect a bill from BT,

I have no ring wire , i have a simple setup, one master socket that is a year old and a MK3 faceplate that is a few days old.

What makes you think i should expect a bill from BT ?
I assume you did not read my initial post fully ".....i am getting 100s of FEC errors a second, was showing on his equipment when he tested at the cabinet and just outside my property"