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CASE 7: IP PBX for SMB Office
SP5325/1S3O
IP PBX SMB
3*FXO
…
SMB Office
PSTN/GSM
PSTN/GSM
ISP/ITSP
Internet
Scale: 50 - 70 users
Extension: SP5325 controls SIP calls among the registered devices SP5103
and SP5004/S (or other FXS gateway).
SIP Trunk: SP5325 registers to ISP/ITSP for inbound/outbound SIP calls.
PSTN Trunk (FXO): Company needs a representative PSTN number for
customers to call. If the direct calling with PSTN number to VoIP network is not
supported by ITSP, FXO ports connect with PSTN lines and allow daily phone
calls from/to PSTN/GSM.
PSTN Backup: SP5325 supports PSTN lifeline on FXS/FXO model. In case of
power failure, users can still make/receive calls via PSTN lines.
SP5103
SIP Phone
SP5004/S
VoIP FXS Gateway
1*FXS
@London
@Paris
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