ASCOM Ascotel 2025 System Manual page 68

3.1.1.1 Basic Access T
Basic access T is suitable for connection to both the public ISDN network and the
private-leased-line network.
3.1.1.2 Basic Access S External
The basic access S external is an interface configured as external ("Port =
S external" setting in the interface configuration).
The basic access S external is designed for the following purposes:
• For connection to the private leased-line network or
• For connecting DSS1 terminal equipment, which evaluates the DDI number
sent by the PBX and routes the call accordingly
(e.g. a fax server, see "Call to a DSS1 Terminal equipment on the S Bus (DDO)",
Page 2.153)
Fig. 1.3: S external in a private leased-line network: PINX-PINX connection
Fig. 1.4: S external in a DDI configuration
Note:
An S interface configured as external is a fully-fledged network interface
and is no longer available as a user-network interface. A basic access
S external cannot be used as a connection to the public ISDN network.
HBT_20321104_01/B0_en
PINX 1
T
haz0641aaena0
PBX
T
222 224 51
...
222 224 55
haz0704aaena0
ascom Ascotel 2025/2045/2065
S external T
Device with
DDI evaluation
S external T
451
...
455
System Interfaces
PINX 2
1.13