AudioCodes Media Pack MP-124, User Manual

Page: 282 / 584

User's Manual 282 Document #: LTRT-65422
MP-11x & MP-124
The following is required:

One FXO interfaces with ports connected directly to the PBX lines (shown in the figure
below)

One FXS interfaces for the 'remote PBX extension'

Analog phones (POTS)

PBX (one or more PBX loop start lines)

LAN network
Figure 25-14: FXO-FXS Remote PBX Extension (Example)
25.15.1 Dialing from Remote Extension (Phone at FXS)
The procedure below describes how to dial from the 'remote PBX extension' (i.e., phone
connected to the FXS interface).

To make a call from the FXS interface:
1. Off-hook the phone and wait for the dial tone from the PBX. This is as if the phone is
connected directly to the PBX. The FXS and FXO interfaces establish a voice path
connection from the phone to the PBX immediately after the phone is off-hooked.
2. Dial the destination number (e.g., phone number 201). The DTMF digits are sent over
IP directly to the PBX. All the audible tones are generated from the PBX (such as
ringback, busy, or fast busy tones). One-to-one mapping occurs between the FXS
ports and PBX lines.
3. The call disconnects when the phone connected to the FXS goes on-hook.
25.15.2 Dialing from PBX Line or PSTN
The procedure below describes how to dial from a PBX line (i.e., from a telephone directly
connected to the PBX) or from the PSTN to the 'remote PBX extension' (i.e., telephone
connected to the FXS interface).

To dial from a telephone directly connected to the PBX or from the PSTN:

Dial the PBX subscriber number (e.g., phone number 101) in the same way as if the
user’s phone was connected directly to the PBX. As soon as the PBX rings the FXO
device, the ring signal is ‘sent’ to the phone connected to the FXS device. Once the