Isdn Q.931 Error Message 41
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and AccessIntegrated Services Digital Networks (ISDN), Channel-Associated Signaling (CAS)Troubleshoot and AlertsConfiguration Example and TechNotes Understanding debug isdn q931 Disconnect Cause Codes Download Print Available Languages isdn cause code list Download Options PDF (30.2 KB) View with Adobe Reader on a variety of isdn cause codes wiki devices Updated:Jul 12, 2005 Document ID:8607 Contents Introduction Prerequisites Requirements Components Used Conventions Cause Code Origination Point Disconnect Cause
Cause Code Technologies
Code Optional Diagnostic field Related Information Introduction This document explains how to interpret Integrated Services Digital Network (ISDN) disconnect cause codes. The ISDN disconnect cause code appears in the debug isdn
Q850 Cause Codes
q931 command output, and indicates the reason for call disconnection. Note:Activate the debug isdn q931 command for this exercise. Remember that the debug isdn q931 command generates a large volume of debugs. Refer to Important Information on Debug Commands for more information on the safe use of debugs. Here is a sample output of the debug isdn q931 command. The output indicates sip cause codes the disconnect cause code for a failed ISDN call: Calling#ping 10.10.10.2 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.10.10.2, timeout is 2 seconds: 20:52:14: ISDN BR0: TX -> SETUP pd = 8 callref = 0x2E 20:52:14: Bearer Capability i = 0x8890 20:52:14: Channel ID i = 0x83 20:52:14: Keypad Facility i = '5551111' 20:52:15: ISDN BR0: RX <- CALL_PROC pd = 8 callref = 0xAE 20:52:15: Channel ID i = 0x89 20:52:16: ISDN BR0: RX <- PROGRESS pd = 8 callref = 0xAE 20:52:16: Progress Ind i = 0x8A81 - Call not end-to-end ISDN, may have in-band info 20:52:16: Signal i = 0x01 - Ring back tone on 20:52:34: ISDN BR0: RX <- DISCONNECT pd = 8 callref = 0xAE 20:52:34: Cause i =0x829F08 - Normal,unspecified or Special intercept, call blocked group restriction 20:52:34: ISDN BR0: TX -> RELEASE pd = 8 callref = 0x2E 20:52:34: ISDN BR0: RX <- RELEASE_COMP pd = 8 callref = 0xAE The 0x in the disconnect code indicates that the subsequent bytes are in hexadecimal format and are not part of the actual code. This table
systems like UDP, ISDN is connection oriented and uses explicit signalling to manage call state: Q.931. Q.931 typically does not carry user
Isdn Cause Codes Pdf
data. Q.931 does not have a direct equivalent in the Internet ss7 cause codes Protocol stack, but can be compared to SIP. Q.931 does not provide flow control or perform 5w56 service retransmission, since the underlying layers are assumed to be reliable and the circuit-oriented nature of ISDN allocates bandwidth in fixed increments of 64 kbit/s. Amongst other things, http://www.cisco.com/c/en/us/support/docs/dial-access/integrated-services-digital-networks-isdn-channel-associated-signaling-cas/8607-isdn-disc-code.html Q.931 manages connection setup and breakdown. Like TCP, Q.931 documents both the protocol itself and a protocol state machine. Q.931 was designed for ISDN call establishment, maintenance, and release of network connections between two DTEs on the ISDN D channel. Q.931 has more recently been used as part of the VoIP H.323 protocol stack (see https://en.wikipedia.org/wiki/Q.931 H.225.0) and in modified form in some mobile phone transmission systems[2] and in ATM. A Q.931 frame contains the following elements: Protocol discriminator (PD) – Specifies which signaling protocol is used for the connection (e.g. PD=8 for DSS1) Call reference value (CR) – Addresses different connections which can exist simultaneously. The value is valid only during the actual time period of the connection Message type (MT) – Specifies the type of a layer 3 message out of the Q.931-defined Message type set for call control (e.g. SETUP). There are messages defined for the call setup, the call release and the control of call features. Information elements (IE) – Specify further information which is associated to the actual message. An IE contains the IE name (e.g. bearer capability), their length and a variable field of contents. Contents 1 Message examples 2 Disconnect causes 3 Q.2931 4 References Message examples[edit] Messages typically control or report the status of connections. For example: SETUP (indicat
to SIP Code Table The following table describes the mappings implemented by FreeSwitch (see mod_sofia.c:hangup_cause_to_sip). Unspecified causes codes (no value in the "SIP Equiv." column in the table) are translated to SIP "480 Temporarily Unavailable" by FreeSwitch. The table https://wiki.freeswitch.org/wiki/Hangup_Causes also contains non-standard codes above 127 (ISUP and ISDN only specify codes up to 127). These codes are used internally to FreeSwitch to indicate other states. (These codes do not map directly to SIP error codes either.) The complete list of SWITCH_CAUSE_ codes (switch_call_cause_t) is defined in include/switch_types.h. See ITU-T Q.850 standard for a formal definition of standard telephony disconnect cause codes for ISDN, and the mapping between Q.931 (DSSS1) and ISUP codes. See cause code ITU Q.1912.5 for a formal definition of interoperability between ISUP and SIP, especially section 6.11 which specifies the "Reason" header and gives the mapping of the disconnect cause codes between ISUP and SIP. Another set of mappings are the Q.SIG / SIP mappings from RFC 4497 section 8.4.1. (Q.SIG is one of many extensions to Q.931 used for PBX-to-PBX signalling on private links.) In practice it appears that FreeSwitch implements neither Q.1912.5 nor RFC4497. ITU-T isdn cause code Q.850 Code SIP Equiv. Enumeration Cause Description 0 UNSPECIFIED Unspecified. No other cause codes applicable. This is usually given by the router when none of the other codes apply. This cause usually occurs in the same type of situations as cause 1, cause 88, and cause 100. 1 404 UNALLOCATED_NUMBER Unallocated (unassigned) number [Q.850 value 1] This cause indicates that the called party cannot be reached because, although the called party number is in a valid format, it is not currently allocated (assigned). 2 404 NO_ROUTE_TRANSIT_NET No route to specified transit network (national use) [Q.850] This cause indicates that the equipment sending this cause has received a request to route the call through a particular transit network, which it does not recognize. The equipment sending this cause does not recognize the transit network either because the transit network does not exist or because that particular transit network, while it does exist, does not serve the equipment which is sending this cause. 3 404 NO_ROUTE_DESTINATION No route to destination [Q.850] This cause indicates that the called party cannot be reached because the network through which the call has been routed does not serve the destination desired. This cause is supported on a network dependent basis. 6 CHANNEL_UNACCEPTABLE channel unacceptable [Q.850] This cause indicates that the channel most recently identified is not accepta