How does QSIG differ from DPNSS?
QSIG is a protocol based closely on internationally agreed Standards for ISDN, whereas DPNSS is a protocol developed before the majority of ISDN standards were agreed and published. The fact that DPNSS is based on pre-ISDN technology in no way diminishes its usefulness and importance as a protocol around which highly featured and complex digital private networks can be built. Both QSIG and DPNSS support similar sets of features.
