Isdn Protocol Stacks; Isdn Application Scenarios - HP MSR Router Series Wan Access Configuration Manual

Item
Countries/areas

ISDN protocol stacks

ISDN provides dial-on-demand links. It sets up and maintains a link only when traffic is present.
The B-channels and the D-channel use separate protocol stacks, as shown in
Table 4 ISDN protocol stacks and OSI reference model
OSI model
Network layer
Data link layer
Physical layer
The following describes the functionality of the protocols in the D-channel protocol stack:
Q.921—Provides the following functions:
•
A reliable transport for Layer 3 Q.931 signaling messages.
Identification of frames.
Flow control mechanisms for data transmission and reception.
Q.931—Provides call control and management. These functions include call setup, call
•
disconnection, and request for services from Layer 2.
Call control (CC)—Forwards messages received by Q.931 from the network side to higher-layer
•
applications such as the DDR or voice module for information conversion and call routing.
Figure 37 ISDN D-channel protocol stack

ISDN application scenarios

Figure 38 and
respectively.
CE1 PRI (30B + D)
•
Most Asia countries (including China)
•
Europe
ISDN layer
Layer 3
Layer 2
Layer 1
Figure 39 show typical ISDN network diagrams for data services and voice services,
D-channel
Q.931, Call Control (CC)
Q.921
I.430 BRI/I.431 PRI
110
CT1 PRI (23B + D)
•
North America (including
USA and Canada)
•
Hong Kong
•
Japan
Table 4.
B-channel
IP, IPX
PPP, HDLC
I.430 BRI/I.431 PRI