Call reference

Associated variants: All except Q.767

Identifies the reference number assigned to a call for use in subsequent messages related to that call. This number has meaning only to the exchange that assigns it. This information element is relevant to BICC only in MTP3- and MTP3b-based signaling networks.

Note: For ANSI networks, use the callRefA structure that supports 24-bit point codes. For ITU-T and BICC, and ETSI networks, use the callRef structure that supports 14-bit point codes. This parameter is relevant to BICC only in MTP 3- and MTP 3b-based signaling networks.

 

typedef struct _callRef      /* Call Reference */
{
    ElmtHdr eh;              /* element header */
    TknU32  callId;          /* call identity  */
    TknU16  pntCde;          /* point code     */
} SiCallRef;

typedef struct _callRefA     /* Call Reference */
{
    ElmtHdr eh;              /* element header */
    TknU32  callId;          /* call identity  */
    TknU32  pntCde;          /* point code     */
} SiCallRefA;

The fields in the SiCallRef and SiCallRefA structures are encoded as follows:

Field

Description

callID

Call identity encoded as a 32-bit quantity of which the least significant 24 bits are used.

pntCde

Signaling point code for the call encoded as follows:

  • In ANSI, a 32-bit quantity of which the least significant 24 bits are used.

  • In BICC, ETSI, and ITU-T, a 16-bit quantity of which the least significant 14 bits are used.

 

For example, an ANSI point code represented by the decimal string 1.4.7 is encoded as the hexadecimal number 0x00010407.


Tokens for the ANSI, BICC, and ETSI variants

Token

ANSI 88

ANSI 92

ANSI 95

BICC

ETSI V2

ETSI V3

callId

*

*

*

*

*

*

pntCde

*

*

*

*

*

*


Tokens for the ITU variants

Token

ITU Blue

ITU White

ITU 97

callId

*

*

*

pntCde

*

*

*