Core Issue
The setup involves Siemens Hicom 300 connected to a Cisco CallManager 4.2 through a E1 QSIG in a Cisco 2851 that uses MGCP. These are the issues experienced:
- Calling name information is not sent from Siemens to Cisco.
The Hicom has two types of QSIG:
- QSIG
- QSIG v2
- When you use QSIG:
When you call Cisco from Siemens or Siemens from Cisco, the Siemens calling name is shown in the Cisco IP Phone but the Cisco name is not shown in the Siemens Phone. In other words, the calling name information is not passed from Cisco to Siemens.
- When you use QSIGv2:
Calls from Cisco to Siemens do not work at all. But calls from Siemens to Cisco do and calling name information is passed in both directions. In other words, it works as it needs to, except that you cannot place calls from Cisco to Siemens.
The debug isdn q931 command shows Facility IE message from Siemens cannot be decoded by the Cisco router.
Resolution
In order to resolve this issue, change ASN.1 ROSE OID Encoding to Use Global Value (ECMA).
Refer to the Compatibility with Older Versions of QSIG Protocol (ECMA) section of Understanding IP Telephony Protocols for more information.
ASN.1 ROSE OID Encoding This parameter specifies how to encode the Invoke Object ID (OID) for remote operations service element (ROSE) operations. Use Local Value (supported by most telephony systems) needs to be used when you use QSIG Variant ISO, Use Global Value (ISO) needs to be used only if the connected PBX does not support local value, and Use Global Value (ECMA) needs to be used if QSIG Variant is ECMA.
This is a required field.
Default: Use Local Value.
Refer to the Q.Signaling (QSIG) section of Understanding IP Telephony Protocols for more information.
