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Abnormal Dialogue Problem

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Dialogic SS7 and SIGTRAN Signalling

Abnormal Dialogue Problem

  • hello :),

    iam facing a problem while sending my response to the network,

    it returns abnormal dialogue error ,

    can any one help me to figure what could cause such an error ?
  • From Q.771



    The Component sublayer will decide to abort a dialogue and discard any components received if an

    incorrect dialogue portion (e.g. syntactically incorrect or inopportune) is received or if no common

    version of the dialogue portion control APDUs can be agreed to. It informs its TC-user via a

    TC-P-ABORT indication primitive with the "P-Abort" in the primitive set to respectively "abnormal

    dialogue" or "no common dialogue portion".

  • thaaaaaaanx alot Martyn ,



    can you give me a hint of how to set the correct dialogue portion?






  • Hi Firas,

     

    I've got the same problem. Did you manage to solve your problem? If yes, how?

     

    Thank You,

    Leila

  • setup.zip

    I have this same error.

    Let me describe our (purported) configuration first -- please see attached system.txt, config.txt and inap_config.ms7:

    1. SCTP: 192.168.1.1:2905 - 192.168.1.2:2905
    2. M3UA: PC 101 - PC 202
    3. SCCP: SSN 146 - SSN 146
    4. TCAP
    5. INAP (CAMEL v3)

    The Dialogic stack runs on the "left" side in SCTP server mode.

    The file inap_config.ms7 is necessary because the s7_mgt module was unable to configure the INAP module. Without printing any error messages, it silently ignored the INAP_CONFIG section of config.txt. Consequently, the unconfigured INAP module threw away all user messages. The inap_config.ms7 file sets up module ID's, dialogue ID ranges, trace options, and defines the CAMELv3 application context. All requests complete successfully (translated trace):

    • S7L:2009-07-21 17:51:14.138 I0000 M R:INAP_MSG_CONFIG i0000 fINAP dLOG r0000 s00 e00000000 p0c14efefef00000080004000c0003fff3fffffff0000000000000000000000000000000000000000
    • S7L:2009-07-21 17:51:14.138 I0000 M R:INAP_MSG_TRACE_MASK i0000 fINAP dLOG r0000 s00 e00000000 p0000000f0000000f0000007f
    • S7L:2009-07-21 17:51:14.138 I0000 M R:INAP_MSG_CNF_AC i0050 fINAP dLOG r0000 s00 e00000000 p00000000000000000704000001150304

    We try to open a dialogue using the INAP API. The INAP module sends a TC-BEGIN message to the TCAP module, but the TCAP module refuses it with P-Abort. Originally we added one invoke (InitialDP) component to the TC-BEGIN packet, but we encounter the same P-Abort with the "empty" TC-BEGIN as well. The problem is reproducible with s7_play, so that's what I will describe below.

    These are the two messages we send to INAP:

    1. M-tc7f2-i0000-fef-d35-r8000-s00-e00000000-p01030443650092010443ca00921b015000
    2. M-tc7f2-i0000-fef-d35-r8000-s00-e00000000-p0300

    First:

    • c7f2: INAP_MSG_DLG_REQ
    • 01: dialogue primitive type: INAP-OPEN-REQ
    • 030443650092: INAPPN_orig_address, length 4, AI: 0x43 (PC + SSN present, route on SSN), PC: 0x65 (101), SSN: 0x92 (146 CAP)
    • 010443ca0092: INAPPN_dest_address, length 4, AI: 0x43 (PC + SSN present, route on SSN), PC: 0xCA (202), SSN: 0x92 (146 CAP)
    • 1b0150: INAPPN_ac_reference, length 1, value 0x50 (INCAP_V3_GSMSSF_TO_GSMSCF_GENERIC)
    • 00: end of message

    Second:

    • c7f2: INAP_MSG_DLG_REQ
    • 03: dialogue primitive type: INAP-DELIMIT-REQ
    • 00: end of message

    The INAP module confirms both messages (translated log):

    • S7L:2009-07-21 17:53:28.082 I0000 M R:INAP_MSG_DLG_REQ i0000 fINAP dLOG r0000 s00 e00000000 p01030443650092010443ca00921b015000
    • S7L:2009-07-21 17:53:28.083 I0000 M R:INAP_MSG_DLG_REQ i0000 fINAP dLOG r0000 s00 e00000000 p0300

    And accordingly, it sends the following message to TCAP:

    S7L:2009-07-21 17:53:28.083 I0000 T 0000058e M tc783 i4000 f35 d14 r0000 s00 e00000000 p02060102070443ca00920804436500920d070400000115030400

    Or, in translated format,

    S7L:2009-07-21 17:53:28.083 I0000 T 0000058e M TCP_MSG_DLG_REQ i4000 fINAP dTCAP r0000 s00 e00000000 p02060102070443ca00920804436500920d070400000115030400

    Parameters:

    • 02: dialogue primitive type: TCPPT_TC_BEGIN
    • 060102: TCPPN_QOS, length 1, indicator bit 1 set: sequence control required
    • 070443ca0092: TCPPN_DEST_ADDR, address as in INAP message
    • 080443650092: TCPPN_ORIG_ADDR, address as in INAP message
    • 0d0704000001150304: TCPPN_APPL_CONTEXT, length 7, application context name 4.0.0.1.21.3.4 (CAMEL v3), as defined in inap_config.ms7
    • 00: end of message

    (Note that we tried to switch the order of the orig and dest addresses, to no avail.)

    Alas, the TCAP module refuses this message (translated log):

    • S7L:2009-07-21 17:53:28.084 I0000 T 0000058e M TCP_MSG_DLG_IND i4000 fTCAP dINAP r0000 s00 e00000000 p060f017e00
    • S7L:2009-07-21 17:53:28.084 I0000 TCAP Maintenance event : TCPEV_DLG_REQ_DISCARD

    Parameters in TCP_MSG_DLG_IND:

    • 06: dialogue primitive type: TCPPT_TC_P_ABORT
    • 0f017e: TCPPN_P_ABORT, length 1, TCPPABT_ABNORMAL_DLG (126, Abnormal dialogue)
    • 00: end of message

    The INAP module translates this abort indication for the original user (translated log):

    S7L:2009-07-21 17:53:28.084 I0000 T 0000058e M INAP_MSG_DLG_IND i0000 fINAP dUSER r0000 s00 e00000000 p050901000c010100

    Parameters:

    • 05: dialogue primitive type: INAP-P-ABORT-IND
    • 090100: INAPPN_prov_rsn, length 1, value 0x00 (provider reason:  provider malfunction)
    • 0c0101: INAPPN_source, length 1, value 0x01 (TC problem)
    • 00: end of message

    If we submit the TC-BEGIN message directly to TCAP with s7_play, in order to request confirmation (because the INAP module doesn't requests confirmation), with a different dialogue ID, as in

    M-tc783-i5000-fEF-d14-r8000-s00-e00000000-p02060102070443ca00920804436500920d070400000115030400

    then the same thing happens as above, but additionally, we receive the following negative confirmation from TCAP (translated):

    S7L:2009-07-21 18:27:36.480 I0000 M R:TCP_MSG_DLG_REQ i5000 fTCAP dLOG r0000 s06 e00000000 p02060102070443ca00920804436500920d070400000115030400

    Where status 0x06 means TCPE_BAD_PARAM, "Invalid parameters contained in the message".

    Could somebody please help with why TCAP finds this TC-BEGIN message invalid? Thank you very much.

  • We solved the problem. It was caused by the incorrect application context name definition in inap_config.ms7:

    M-t77F6-i0050-fEF-d35-r8000-p00000000000000000704000001150304

    The corrected version (inserted octets are bold and underlined)

    M-t77F6-i0050-fEF-d35-r8000-p00000000000000000BA109060704000001150304

    Having no previous Q.773 and X.209 experience, we were misled by a typo in U16SSS12-INAP-PM.pdf. There are two instances of this typo:

    • 3.6 INAP Dialogue Primitive Paramteres, INAPPN_applic_context, page 25: "Encoded as specified in Q.773 commencing with the Object Identifier Name tag."
    • 5.5 INAP Application Context Configuration Request, Application Context, page 66: "Encoded as specified in Q.773 commencing with the Object Identifier Name tag."

    There is no such thing as an Object Identifier Name tag. It's either Object Identifier tag (0x06), or Application Context Name Tag (0xA1). We interpreted the typo as the former, but the correct interpretation is the latter. So when defining the application context, one has to encode not only the (contents) of the OID, but the entire Application Context Name constructor:

    • 0B: application context length (U16SSS12-INAP-PM.pdf, INAP_MSG_CNF_AC)
    • A1: constructor tag for Application Context Name, IOW Application Context Name Tag (T-REC-Q.773-199706.pdfTable 43/Q.773)
    • 09: length of constructor body = 9 (Application Context Name Length, Table 38/Q.773)
    • 06: object identifier tag (T-REC-X.209-198811.pdf, 22 Encoding of an object identifier value)
    • 07: object identifier length = 7
    • 04000001150304: OID contents

    We realized that the problem was technically caused by our incorrect INAP configuration when we looked at other application context definitions in RUN/INTU/SCRIPTS/inapcfg.ms7 (from upd.tar, V5.00).

  • Thanks for taking the trouble to mention the typo in the manual. We've marked this up for correction when we next release the manual to avoid confusion for others.