Is there an acceptable amount of c-bit, p-bit errors on a DS3?

[brianhill88]

We were having a problem with a DS3 that terminates in a 3845 that was reporting about 1000 c-bit errors a day.  AT&T isolated the problem and fixed it.  Now we see about 70 c-bit errors a day.

T3 1/0 is up.
  Applique type is Subrate T3
  No alarms detected.
  MDL transmission is disabled

  FEAC code received: No code is being received
  Framing is C-BIT Parity, Line Code is B3ZS, Clock Source is Internal
  Data in current interval (640 seconds elapsed):
     0 Line Code Violations, 14 P-bit Coding Violation
     14 C-bit Coding Violation, 14 P-bit Err Secs
     0 P-bit Severely Err Secs, 0 Severely Err Framing Secs
     0 Unavailable Secs, 0 Line Errored Secs
     14 C-bit Errored Secs, 0 C-bit Severely Errored Secs
  Total Data (last 24 hours)
     0 Line Code Violations, 69 P-bit Coding Violation,
     69 C-bit Coding Violation, 69 P-bit Err Secs,
     0 P-bit Severely Err Secs, 0 Severely Err Framing Secs,
     0 Unavailable Secs, 0 Line Errored Secs,
     69 C-bit Errored Secs, 0 C-bit Severely Errored Secs

Every once an while we've seen a few errors on this line before but I'm wondering if there is an acceptable amount?  Is 69 in a 24 hour period too many?  At what point should we be concerned?

Thanks

[paolo bevilacqua · Accepted solution]

Seem acceptable, but I recommend you perform extended BERT testing, either layer 1 or layer 3 with different patterns.

Note I see you have clock itnernal, are you sure that is the correct setting ?

[brianhill88]

I'm double checking with AT&T to confirm that is the correct setting but I'm pretty sure they do not provide clock.  But what I did notice is that both routers on either side of the circuit are set to "clock source internal" which means they are both doing their own thing right?  Without one of them set to clock source line they are not synced correct?

[paolo bevilacqua · Accepted solution]

When a circuity truly do not provides clock (unusual), only one of the routers must be set to  internal.

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[brianhill88]

I confirmed with AT&T that they do not provide clock on this circuit.  But your observation about the clock lead me to see that both routers were set to internal.  We're going to schedule a maintenance to change that.  Thanks for you help!