Isdn parameters – general – 2N StarGate/BlueTower v5.3 User Manual
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frequency of queries routed to the STUN server.
Note
In case the GSM gateway is installed behind the NAT, make
proper routing settings in the NAT router for the relevant ports
(SIP, RTP, STUN). Integrated firewalls can also affect VoIP calls!
Tip
Should you have call troubles (such as unilateral audibility,
connection errors), make sure that all the active elements on
the VoIP call route have been set properly. For easy
troubleshooting, try the point–to–point connection with the
software IP phone (SJ phone, e.g.) in your PC and, at the same
time, apply network analyser tracing (WireShark –
Refer to the
subsection for easy tracing by
2N
®
.
StarGate / BlueTower
Tones Generated to VoIP
– generate a ringing tone of your own, or transmit a real
Ring tone to VoIP
ringing tone from the GSM/UMTS networks.
ISDN Parameters – General
Use this window to set the PRI ISDN port parameters.
PRI Mode Selection
Here define the PRI 1 (2) ISDN port type.
Synchronisation – define if the gateway will send the synchronisation clock
(MASTER) or receive the synchronisation clock from the connected line (SLAVE).
PRI1 / PRI2
Channel number select – define the way of occupation of B–channels on a
selected ISDN PRI interface. With the UPWARDS selection, the gateway will
occupy the B–channels upwardly (from the selected B–channel number to the
B–channel 32). With the DOWNWARD selection, the gateway will occupy the
B–channels in the descending order (from the selected B–channel number to
B–channel 1).
Preferred channel – select a B–channel.
Note
The PRI 1 port is always set as internal – the LCR function is
activated. The PRI 2 port is always set as external – all calls
from PRI 2 are rerouted to PRI 1. The PRI 2 port has a mode
opposite to that of the PRI 1 port.
In the case of ISDN port mode change, change the selection of
the ISDN PRI card jumpers, see the PRI Board subsection.