ASCOM Ascotel 2025 - Page 73

ascom Ascotel 2025/2045/2065
1.18 System Interfaces HBT_20321104_01/B0_en
3.1.2 Primary Rate Access T2
A primary rate access is a digital network interface for connection to the public
network or the private leased-line network. It can be set for the protocols DSS1
(public ISDN network) and QSIG / PSS1 (private leased-line network).
A primary rate access has thirty 64 kbit/s user information channels and one
64 kbit/s control and signalling channel (30B+D). One call or data connection can
be set up on each bearer channel (B channel) simultaneously and independently
of the other B channel.
Note:
Primary rate accesses can only be used as point-to-point connections.
NT1: Network Terminal
U2/U/T2/T:ISDN reference points
30B+D: Primary rate access channels
2B+D: Basic access channels
AD2: Digital user-network interface AD2
S: User-network interface S
a/b: Analogue user-network interface a/b
Fig. 1.9: System with basic and primary rate accesses
Fig. 1.10: Primary rate access in a private leased-line network: PINX-PINX connection
Channels
U2
U
U
T2
T
T
AD2
S
a/b
PBX
NT1
NT1
NT1
30B+D
2B+D
2B+D
haz0323aaena1
T2T2 T2
PINX 1 PINX 2
haz0705aaxxa0