Cisco VG30D, User Manual

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Cisco VG30D Voice Gateway User Guide
OL-19276-01
Chapter 6 Conversions and Transparency
Advanced Service Interworking
QSIG
Step 1
Go to Configuration / Q.931 Services
Step 2
Check the box beside Enable Name Identification Service to enable the QSIG name supplementary
service.
Step 3
Select from the list beside Name Text to Display element Mapping and click SUBMIT .
Route Optimisation Options
The DPNSS Services Configuration window provides two additional options when DPNSS Services /
Enable Route Optimisation Service and Q.931 Services / Enable Path Replacement Service are
checked:
• PBX accepts Route Optimisation Invite String
•
Restrict Route Optimisation Call Ref. Mapping
Use of DPNSS Route Optimisation Invite String
If you selected full interworking. Cisco VG30D Voice Gateway can occasionally persuade the network
to achieve more effective call routing by issuing a “ROP-INV” request to the DPNSS PBX. ROP-INV
was a late addition to the DPNSS specification, so not all DPNSS PBXs support this request. It can
prevent some of those PBXs from achieving correct Route Optimisation. You may need to ask your PBX
supplier, or experiment to determine whether your PBX accepts this string.
If the DPNSS PBXs attached through this unit support ROP-INV, then no calls will fail. However, if you
are in any doubt about the ability of your DPNSS PBXs to handle ROP-INV, you should not check the
box beside
PBX accepts Route Optimisation Invite string in DPNSS Services , because correctly
operating Route Optimisation without ROP-INV is better than incorrect operation if the PBX does object
to the Cisco VG30D Voice Gateway’s use of this signalling.
Restricted Route Optimisation Call Reference Mappings
When the Cisco VG30D Voice Gateway interworks the QSIG Path Replacement Network Feature with
DPNSS Route Optimisation, it constructs a DPNSS Call Reference value from the Path Replacement
parameters that are provided in QSIG, and vice versa. The service parameter definitions do not always
match exactly. This has been rectified only in the most recent DPNSS specification (issue 7), and many
PBXs do not implement the upgraded standard.
QSIG Facility Element Encoding
Cisco VG30D Voice Gateway’s QSIG Protocol and Supplementary Services support can comprise any
one of three different QSIG definitions:
•
The original definition defined by ECMA on behalf of ETSI in 1993 (ETS 300 172 / ETS 300 239
versions 1 & subsequently adopted service specifications).
•
The ISO definition, adopted in 1994 (ISO/IEC 11572/11582:1995 & services).
• The ISO-aligned definition adopted by ETSI in 1995 (ETS 300 172/239 versions 3 & services).