Private Integrated Services Network (PISN)
- Inter-Exchange Signalling Protocol - Transit Counter Additional
Network Feature (QSIG-TC)
2nd edition (June 1997)
This Standard specifies the signalling protocol for the support
of the Transit Counter additional network feature (ANF-TC) at
the Q reference point between Private Integrated Services Network
Exchanges (PINXs) connected together within a Private Integrated
Services Network (PISN).
ANF-TC is a feature that limits the number of Transit PINXs that
a call setup request may be routed through e.g., to protect the
network against indefinite looping.
The Q reference point is defined in ISO/IEC
Service specifications are produced in three stages and according
to the method specified in ETS 300 387. This Standard contains
the stage 3 specification for the Q reference point and satisfies
the requirements identified by the stage 1 and stage 2 specifications
The signalling protocol for ANF-TC operates in association with
the signalling protocols for basic circuit switched call control
(as specified in ECMA-143) and call
independent (connection oriented) signalling connections (as specified
This Standard also specifies additional signalling protocol requirements
for the support of interactions at the Q reference point between
ANF-TC and other supplementary services and ANFs.
This Standard is applicable to PINXs that can interconnect to
form a PISN.
The protocol defined in this Standard forms part of the PSS1
protocol (informally known as QSIG).
The following file can be freely downloaded:
||Acrobat (r) PDF file
This Ecma publication is also approved as ISO/IEC 15056.
The previous replaced "historical" edition of this Ecma Standard is available here.