Chapter 2 Q-SIG FEATURES
2-2
NWA-088654-001 Rev.1.0
94ch2001.fm
SYSTEM OUTLINE
SYSTEM OUTLINE
Summary
This system provides the basic connection service for interfacing with the other PBX by using Layer 3
protocol which conforms to ETS 300 172. ETS 300 172 is standardized for private telecommunication
network as Inter-exchange signaling protocol for circuit mode basic services by European Telecommuni-
cation Standards Institute (ETSI). The Q-SIG protocol creates Layer 3 messages between Q reference
points expected as conceptual point for inter-office signalling.
System Outline of Q-SIG
NOTE:
Conforming to Q921-a (PBX-PBX Interface)
PBX
PRT
Data Link
Layer
Physical
Layer
Call
Control
Protocol
Control
Q
PBX
DTI
Data Link
Layer
Physical
Layer
Call
Control
Protocol
Control
Q
PRT
Q-reference point
Layer 3
Layer 2
NOTE
Layer 1