When you use a Private Branch Exchange (PBX) connected to a Cisco
CallManager through an E1 Q Interface Signalling Protocol (QSIG) in a Cisco
voice gateway using Media Gateway Control Protocol (MGCP), the calling name is
not displayed. Forwarded calls from different vendors are also dropped.
There are no specific requirements for this document.
The information in this document is based on Cisco CallManager
The information in this document was created from the devices in a
specific lab environment. All of the devices used in this document started with
a cleared (default) configuration. If your network is live, make sure that you
understand the potential impact of any command.
Technical Tips Conventions for more information on document
The QSIG protocol, a series of international standards, defines
services and signaling protocols for Private Integrated Services Networks
(PISNs). These standards use Integrated Services Digital Network (ISDN)
concepts and conform to the framework of International Standards for Open
Systems Interconnection as defined by ISO/IEC. The QSIG protocol acts as a
variant of ISDN D-channel voice signaling. The ISDN Q.921 and Q.931 standards
provide the basis for QSIG protocol, which sets a worldwide standard for PBX
In a basic QSIG call, a user in a Private Integrated Services Network
Exchange (PINX) can place a call to a user that is in a remote PINX. The called
party receives the caller name or number as the call rings. The calling party
receives the called name and number when the user phone rings in the remote
PINX. All the features that are available as a PBX user operate transparently
across the network. QSIG protocol provides supplementary and additional network
features, as defined for PISNs, if the corresponding set of QSIG features are
supported by both ends of the call.
When you use QSIG protocol version 2, if a Cisco IP phone forwards a
call to another Cisco IP phone that is placed from a third party phone, the
first phone call is dropped. Similarly, when a third party phone call is
forwarded to another third party phone that is placed from a Cisco IP phone,
the first phone call is dropped.
When you use QSIG protocol and you call a Cisco IP phone from a phone
connected to a third party PBX or a third party phone from a Cisco IP phone,
the third party phone calling name is shown in the Cisco IP phone, but the
Cisco IP phone calling name is not shown in the third party phone. In other
words, calling name information is not passed from Cisco CallManager to the
third party PBX. This issue is documented in Cisco bug ID
(registered customers only)
These problems can occur if the facility message from third party PBX
cannot be decoded by the Cisco CallManager.
In order to create Cisco CallManager compatibility with your version of
the QSIG protocol, configure the ASN.1 ROSE OID encoding and QSIG Variant
service parameters. The problem described in this document can be solved when
you change the ASN.1 ROSE OID encoding to Use Global
Value (ECMA). Complete the procedure in this section in order to
change the ASN.1 ROSE OID.
Note: The ASN.1 ROSE OID 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) should be used when you use
QSIG Variant ISO. Use Global Value (ISO) should be used only if the connected
PBX does not support Local Value. Use Global Value (ECMA) should be used if
QSIG Variant is ECMA. This is a required field. The default is Use Local
Go to the CallManager Administration page and choose
Services > Service Parameters in order to
go to System Parameters.
Go to the Advanced tab.
Find the Parameter Name ASN.1 ROSE OID Encoding
under Clusterwide Parameters (Device - PRI and MGCP gateway) and change the
parameter value to Use Global Value (ECMA). This is used if
the Q.SIG Variant service parameter is set to ECMA (Protocol Profile
Note: The default value for ASN.1 ROSE OID Encoding is
Use Local Value, which is supported by most telephony systems
and must be used when the Q.SIG Variant service parameter is set to ISO
(Protocol Profile 0x9F).