R2 signalling problem

[moosk]

Hello.
We have Definity 6.3
We also have an E1 link with R2 signalling ( this is an old common channel signalling mode). This is connected to a TN464F board.
We also have two TN744D call classifier boards, that are supposed to handle this signalling.
Avaya guys say that all is configured correctly.

BUT:
The telecom company that sends traffic says that we don`t pick up some of the calls that are directed to our switch via this E1 . Like 'no answer' . In a month span it is about 10% calls.
All calls should be answered, since calls are configured to go to an IVR machine.
This is not a problem with the link being all busy.
This is not a problem with the IVR machines.

I cannot find ANY specific pattern about these unanswered calls. To me this is a random process, happening at random time, on random destination numbers (these numbers are otherwise working correctly). Call it Poisson process .
Just more unanswered calls, when there are generally more calls (a percentage of calls is getting unanswered).

Has a similar problem happened to any of you before? How did You solve it? What to look for?

 

[dimas]

Hi
R2 protocol still popular somewhere...

For helping, please show screens:
disp ds1 xxx
disp trunk xx (page1)
disp sys multifrequency (all pages)

And what type of remote side switch you are connected?

 

[moosk]

Hello.
I don`t really know the type of the other switch. It is a switch from former Polish national operator, Telekomunikacja Polska.

Below are the screens You requested.

#display ds1 1a15

            Location: 01A15                           Name: trakt z TPSA
            Bit Rate: 2.048                    Line Coding: hdb3

      Signaling Mode: CAS

        Interconnect: CO                  Country Protocol: 22

Interface Companding: alaw                             CRC? n
           Idle Code: 01010100


              Received Digital Metering Pulse Minimum (ms): 100
              Received Digital Metering Pulse Maximum (ms): 150

      Slip Detection? y                 Near-end CSU Type: other




#disp tr 1

Group Number: 1                    Group Type: did           CDR Reports: y
  Group Name: TPSA                        COR: 1        TN: 1        TAC: 801


                          Country: 22
                                    Auth Code? n


TRUNK PARAMETERS
            Trunk Type: immed-start      Incoming Rotary Timeout(sec): 5
                                                   Incoming Dial Type: mf
     Trunk Termination: 600ohm                Disconnect Timing(msec): 500
       Digit Treatment: insertion                              Digits: 0
       Expected Digits: 6                           Sig Bit Inversion: none
     Terminal Balanced? n                               RA Trunk Loss: 0db
   Extended Loop Range? n         Trunk Gain: high     Drop Treatment: busy

 Disconnect Supervision - In? y



#disp sys multifrequency 

          Incoming Call Type: group-ii-mfc           ANI Prefix: 0700
          Outgoing Call Type: group-ii-mfc          ANI for PBX: 0700
       Maintenance Call Type: none          NEXT ANI DIGIT
         Test Call Extension:                          Incoming: send-ani
      Interdigit Timer (sec): 10                       Outgoing: send-ani
     Maximum Resend Requests:
   Received Signal Gain (dB): 0
Transmitted Signal Gain (dB): -3
                             Request Incoming ANI (non-AAR/ARS)? n
                    Outgoing Forward Signal Present Timer (sec): 15
                     Outgoing Forward Signal Absent Timer (sec): 30
          Multifrequency Signaling Incoming Intercept Treatment? n
                              Collect All Digits Before Seizure? n
                   Overlap Sending on Link-to-Link Tandem Calls? n
           Private Group II Permissions and Public Interworking? n

                                 Group II Called Party Category: user-type
                             Use COR for Calling Party Category? n


  Request Call Category at Start of Call: n
        Restart ANI from Caller Category? y
           Number of Incoming ANI Digits: 0
           Number of Outgoing ANI Digits: 0
          Truncate Station Number in ANI: no

                        INCOMING    OUTGOING
          ANI Available:
      ANI Not Available:



INCOMING FORWARD SIGNAL TYPES           INCOMING BACKWARD SIGNAL TYPES
(Tones from CO)                         (Tones to CO)

      Group-I             Group-II            Group-A             Group-B
 11: ignored          1: normal          1 : next-digit      3 : busy
 12: ani-not-avail    2: normal          3 : end-of-dial     4 : congestion
 13: ignored          3: normal          5 : send-ani        5 : intercept
 14: ignored          4: normal            :                 6 : free
 15: end-of-ani       5: normal            :                   :
                      6: normal            :                   :
                      7: normal            :                   :
                      8: normal            :                   :
                      9: normal            :                   :
                     10: normal            :                   :
                     11: normal            :                   :
                     12: normal            :                   :
                     13: normal            :                   :
                     14: normal            :                   :
                     15: normal            :                   :





OUTGOING FORWARD SIGNAL TYPES           OUTGOING BACKWARD SIGNAL TYPES
(Tones to CO)                           (Tones from CO)

      Group-I             Group-II            Group-A             Group-B
 12: ani-not-avail   1 : normal           1: next-digit       1: free
 15: end-of-digits   1 : attendant        2: last-digit       2: busy
   :                 6 : data-call        3: end-of-dial      3: busy
   :                   :                  4: congestion       4: busy
   :                   :                  5: send-ani         5: busy
                       :                  6: setup-sppath     6: free
                       :                  7: last-2-digits    7: free
                       :                  8: last-3-digits    8: busy
                       :                  9: congestion       9: busy
                       :                 10: congestion      10: busy
                       :                 11: congestion      11: busy
                       :                 12: congestion      12: busy
                       :                 13: congestion      13: busy
                       :                 14: congestion      14: busy
                       :                 15: congestion      15: busy

 

[dimas]

Hi
Do you route your incoming call to the vector? If so - try to set into the first step something like that:
01 wait-time 2 sec hearing ring-back
May be it helps.
If you can take OUTGOING MULTIFREQUENCY SIGNALING TABLE from operator's switch try to compare the signals with your INCOMING signals - all should be identical.
If you can't compare the tables you could try to change something in your table - for example to change incoming forward signals as following:
GORUP-I
11 ignored
12 ignored
13 ignored
14 ignored
15 end-of-dial
But test the calls right away after changing and if bad result change it back.
regards