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Acceptable crc, fec, hec ?

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mand:
Evening all
Just started to watch my telnet stats via routerstats.
Can someone let me know what is acceptable figures for crc, fec, hec please - mainly downstream figures given:
crc is at 350 - from 250 in 2 hours. One sudden jump about 40 at about 9pm.
fec is at 2million - from 250,000 in 2 hours with the largest jumps at about every half hour since 8.30pm.
hec is 0 downstream, but 272 upstream in 2 hours.
This evening snr margin is averaging 5, when it was 12 ave in the morning.
Thanks Mand

roseway:
By and large you can ignore FEC errors. They are errors which have been autocorrected by the Forward Error Correction process, which is enabled when your connection is interleaved. Large number are not unusual.

CRC and HEC errors don't look particularly high, but I'm no expert so I can't really say what is acceptable.

Ezzer:
With errors ther's a difference in what's acceptable between non interleaved & interleaved, and error issues could crop up seperate from any indication from any hint of a problem from your snr.

The analogy I use for the 3 main types of figures to look at:

Attenuation/loop loss;   It's like listening to someone or radio at the end of the garden/road, if ther'e too far away then you can't make out whats being said unless they talk slower.

SNR/SNR margin;  same situation as above, but if a neighbour has started mowing the lawn, then your trying to make out whats said over the backround row of the mower.

Errors; Like reading a document with the odd spelling/punctuation error. The odd few, no problem. If there are loads then the document becomes difficult or impossible to read

CRC errors are the most critical, closely followed by HEC errors, FEC & RS much less of a problem.

non interleaved 0-30 errors are typical, 60-70 hmm might watch this for a while just in case
>100 you've got a problem, solutions are similar in trying to cure snr issues.

interleaved crc & hec errors up to 9000-11000 ok. rs errors 15000-16000 are ok

Those are basied on running a test between 1-5min's, and on a either a BTw woosh test or a BT Openreach engineers APtS test.

I'm not very sure how all the different routers exactly compair to the way the bt tests run ie are they displaying a cumilative figure or snap shot figure over short time periods

kitz:
>> are they displaying a cumilative figure

Most would appear to display cumulative since last boot or sync.

mand:
Ok thanks for that.
A bt guy was here yesterday and changed the external wire that goes from where the bt line comes out of the ground right to the other side of my house where the mastersocket is. Original wire is supposedly for interior use so he put in an external wire. I had called him out due to new background noise on the land phone.
On connecting the router it synched at 4383kbps, with 6db margin as usual, but now it has stayed like that all evening, working fine even as margin dropped to 1db. Overnight my Ip profile has gone from 750kbps to 3500kbps and my actual throughput is 1826kbps on bt speedtester, and 2700kbps on bbmax speedtest.
All crc, fec, hrc errors are looking good and the phone is clearer   ;D
Mand

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