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CASE 8: Integrating FXS Gateway with Legacy
PBX for SMB Office
SP5004P/SP5018A
VoIP FXS Gateway
with PSTN lifeline
8*PSTN
SMB Office
PSTN/GSM
PSTN/GSM
8*FXS
Legacy PBX
ISP/ITSP
Internet
ISP/ITSP
Telephone
Telephone
…
Scale: 30 - 50 users (or more)
Extension: Legacy PBX has control of extension calling as before.
SIP Trunk: SP5004P/SP5018A connects legacy PBX via FXS ports, and
registers to ISP/ITSP for outbound calls.
PSTN Trunk: PSTN ports of SP5004P/SP5018A are used for regular PSTN
inbound.
PSTN Backup: In case of power failure, users can still make/receive calls via
PSTN lines.
@London
@Paris
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