just been upgraded to max dsl - my stats now

antc

antc

antc

Associate
Joined
23 Jun 2005
Posts
1,773
Location
Nottinghamshire
DATA RATE
uptream - 448
downstream - 8128

NOISE MARGIN
upstream - 22db
downstream - 12.5db

ATTENUATION
upstream - 4db
downstream - 6db

i know seem to be getting some other things showing up though

FAST PATH CRC ERRORS (near end indicator) - 2413
FAST OATH HEC ERROR (near end indicator) - 2446 and (far end indicator) 2446


are these stats ok now that i have been upgraded and what on earth are the errors thats im getting. i have noticed that the connection has dropped a couple of times but not too bad.
 
ooooho a nice 8mbit there!!

I'm too far away to get that. :(

I think within the next 10 days of the line being changed over they run checks to see what the line is best suited at. So tbh, i wouldnt worry.
 
The CRC errors are worrying, However these can be caused by a line outage as opposed to line quality, i'd reset all your counters and monitor it over the next week to see whats actually going on.
 
Skilldibop said:
However these can be caused by a line outage as opposed to line quality
Click to expand...

The more I see of your posts, the more I wonder how much stuff you make up as you go along?

CRC errors are cyclic redundancy check errors. They're caused mainly by random bursts of noise on the line, making data frames useless. Not by outages or anything else.
 
Could those 'Random bursts of noise' be because of interference?
Do you have wireless telephones, wireless network etc?
You might want to get one of those filter front plates for your master socket to stop and interference.
 
Depends how long the connection's been up (and how much traffic you've shifted across it in that time) whether they're relevant though.
 
OllyM said:
The more I see of your posts, the more I wonder how much stuff you make up as you go along?

CRC errors are cyclic redundancy check errors. They're caused mainly by random bursts of noise on the line, making data frames useless. Not by outages or anything else.
Click to expand...

Making it up/ Experience. Whatever you wanna call it. Take the leased line down between 2 ciscos and look at the CRC counters on the serial interfaces. They will keep clicking up and up and up. The reason being it reads random noise on the dead line as a corrupted transmission. Also just before the line goes down you will get a sudden sharp increase in CRC errors, especially so if there are TCP sessions over that link.

The poin being that those 2000 CRCs are probabl caused by the upgrade itself and not poor line quality.
 
i thought crc errors are packets that are not received or sent properly and have to be sent again, so as long as there isnt loads within seconds the line should be ok?
mine has 12,000 fast far end crc errors since 9am yesterday is that bad? line hasnt dropped but snr has gone down to atleast 1db last night
 
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WOMBATWILSON said:
i thought crc errors are packets that are not received or sent properly and have to be sent again, so as long as there isnt loads within seconds the line should be ok?
mine has 12,000 fast far end crc errors since 9am yesterday is that bad? line hasnt dropped but snr has gone down to atleast 1db last night
Click to expand...

That's quite bad. though if your router knows what it's talking about and they are far end errors there's not a whole lot you can do about it.

CRCs is where a mathematical calculation is performed on the packet to reach a value, which is then slapped in the packet. At the other end the same happens and if the two values don't match the packet is dropped as "bad"
 
OllyM said:
But here we're talking about ADSL, not a leased line? Totally different things.
Click to expand...

As far as the router is concerned there's little or no difference. The router sees it as a WAN interface it doesn't actually care what kind of interface. Seeing as most household routers can only display CRC errors and not frame, input, giant, runt, overrun errors then pretty much any error from that interface will go in the CRC box.
 
You get these errors on any line that's operating at its sync capacity. I have a 1Meg ADSL line (can't get any higher) and it gets at least a thousand CRC errors per day...

If you are indeed getting sync drops due to the CRC errors then technically the "RAMBO" system BT uses on MaxDSL should detect the problem after a while and reduce the sync rate ever so slightly until the problem does not occur.

Making it up/ Experience. Whatever you wanna call it. Take the leased line down between 2 ciscos and look at the CRC counters on the serial interfaces. They will keep clicking up and up and up. The reason being it reads random noise on the dead line as a corrupted transmission. Also just before the line goes down you will get a sudden sharp increase in CRC errors, especially so if there are TCP sessions over that link.

The poin being that those 2000 CRCs are probabl caused by the upgrade itself and not poor line quality.
Click to expand...
Bolded the parts that are simply not true/were made up.
Italic'd the parts that could be true but there's no reason to believe that is the case.
 
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I do know for a fact that with a serial connection into a Cisco router, if you disconnect the line you can get CRC's in fact I had this very thing happen yesterday when testing a line.

Also if you take the leased line connection down (by removing the cables), the protocol will drop and you will not see any errors increasing on the line, so that is rubbish. CRC's error normally indicate a physical problem with any line, doesnt just have to be leased lines, xDSL will do the same as well.

As far as the OP, if you can reset the counters then do so and see how often they are increasing, if you are getting a few every minute then to be honest I really wouldnt worry about it too much, if you are seeing other problems like packet loss and high latency then I would get it investigated.
 
The CRC error counter should reset when the connection synchs up.
If they get high enough, there's a good chance the DLM kit will (as NathanE said) reduce your sync rate, or switch interleaving on.

For what it's worth, my ADSL's been in sync for 28 hours, and has a total of 12 downstream CRC errors, and 9 upstream CRC errors.
 
Just to give you another idea my router has the following :-

Code: 
uptime is 1 week, 6 days, 9 hours, 24 minute


                 Interleave             Fast    Interleave              Fast
Speed (kbps):             0             2272             0               288
Cells:                    0          9094215             0         231185965
Reed-Solomon EC:          0                0             5                 4
CRC Errors:               0             4341            14                58
Header Errors:            0             1366             6                16
Bit Errors:               0                0
BER Valid sec:            0                0
BER Invalid sec:          0                0
 
Code: 
Modemstate            :  up 
Operation Mode        :  G.DMT Annex A  [POTS Overlay Mode]
Channel Mode          :  fast 
Number of resets      :  127 

Vendor                              Local           Remote   
  Country             :               0f               0f 
  Vendor              :             ALCB             ALCB 
  VendorSpecific      :             0000             0000 
  StandardRevisionNr  :               01               01 

                                  Downstream        Upstream 
Margin       [dB]     :             18.5             27.0 
Attenuation  [dB]     :             54.0             31.5 
OutputPower  [dBm]    :             16.0             12.0 

Available Bandwidth                 Cells/s           Kbit/s 
  Downstream          :             2716             1152 
  Upstream            :              679              288 


Transfer statistics
  Total since power On              Cells             Kbit
    Downstream        :         94205553         39942920  
    Upstream          :         69271388         29370904  
  Current Connection 
    Downstream        :         94199581         39940376 
    Upstream          :         69263831         29367512 
    Errors 
      Received FEC    :                0 
      Received CRC    :             4657 
      Received HEC    :             3197 
      Transmitted FEC :                8 
      Transmitted CRC :               51 
      Transmitted HEC :               25 

    Far End Failure 
      No Failure 
    Near end failure 
      No failure 
    Far end failures since reset
      Loss of frame:          0 failures 
      Loss of signal:        28 failures 
      Loss of power:          0 failures 
      Loss of link:         126 failures 
      Errored seconds:     4523 seconds  
    Far end failures last 15 minutes 
      Loss of frame:          0 seconds  
      Loss of signal:         0 seconds  
      Loss of power:          0 seconds  
      Loss of link:           0 seconds  
      Errored seconds:        0 seconds  
    Far end failures current day
      Errored seconds:        9 seconds  
    Far end failures previous day
      Errored seconds:        5 seconds  
     Near end failures since reset
      Loss of frame:          0 failures 
      Loss of signal:       126 failures 
      Loss of power:          0 failures 
      Errored seconds:    15795 seconds  
     Near end failures last 15 minutes
      Loss of frame:          0 seconds 
      Loss of signal:         0 seconds 
      Loss of power:          0 seconds 
      Errored seconds:        5 seconds 
     Near end failures current day 
      Errored seconds:      335 seconds 
     Near end failures previous day 
      Errored seconds:      531 seconds

I think I have one of the worst lines in the country :p Luckily my 510v4 just about holds it together ;)
 
I would love a line that good, look at mine

DSL Status: UP
DSL Modulation Mode: GDMT
DSL Path Mode: FAST
Downstream Rate: 1536 Kbps
Upstream Rate: 448 Kbps
Downstream Margin: 6 db
Upstream Margin: 17 db
Downstream Line Attenuation: 63
Upstream Line Attenuation: 31
 
this is mine since yesterday morning

ADSL Current Status Table
Item Value
ADSL Line Type GDMT
ADSL Line Coding FAST
Line Attenuation (Down):51 (Up):31
Noise Margin (Down):6 (Up):20
Total Output Power (Down):0 (Up):0
Current Rate DownStr: 6048(K) UpStr: 448(K)
ADSL Line Status UP
FEC(FAST) (Near):680 (Far):0
FEC(INTERL) (Near):0 (Far):0
CRC(FAST) (Near):73 (Far):17842
CRC(INTERL) (Near):0 (Far):0
HEC(FAST) (Near):0 (Far):0
HEC(INTERL) (Near):0 (Far):0
Showtime last(sec) 108715
ADSL_FW_Version 0.49
ADSL_Board_Type Annex A
 
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