6
6
.
.
3
3
.
.
2
2
.
.
3
3
D
D
u
u
a
a
l
l
M
M
o
o
d
d
e
e
(
(
4
4
S
S
4
4
O
O
）
）
）
）
）
）
）
）
FXO
PSTN EXCHANGER
IP PHONE
NOTIFY TO RING
FXO SEIZES LINE
VOICE
FXO OFFHOOK
IP PHONE
OFFHOOK
FXO DETECT RING
CALLER ID
FXO DETECT RING
NOTIFY TO SEND CID
NOTIFY TO RING
OPEN LOOPBACK CHNL
NOTIFY FXO OFFHOOK
Fig 71
Dual Mode Flow Diagram
Dual mode provides bridge function between pairs of FXS and FXO ports, which
requires all subcards to be 4FXS4FXO. Dual mode can be applied to the user who has
PSTN lines, and wants VOIP function at the same time. PSTN line of user connects to FXO
port, and phone connects to FXO port. Then when a call from PSTN to IP (in PSTN-To-IP
direction), the extension of FXS corresponding to FXO port rings immediately; if phone of
FXS call out, it can choose both IP and PSTN route.
Tips:
Dual mode can guarantee the Caller ID of PSTN side transport
transparently function, which is not under the control of “Ring Times
Detected”.
Related Configurations
：
Step 1: Advanced Configure ---> FXO ---> FXO Advanced Configuration: “Working
Mode” = “Dual Mode”; ( refer to section
5.4.2
)
Step 2: Advanced Configure ---> FXO ---> “Enable PSTN CallerID” = “Yes”; ( refer to
section
5.4.2
)
Step 3: NBR Exchange ---> ChangeRule ---> Number Change Rule Table:
“ChangeType” = “DelPrefix”, “ChangeLen”= 1; (refer to section
5.5.3
)
Step 4: NBR Exchange ---> CallerChange ---> Caller Number Change Rule Index:
configure “Caller Number Change Rule Index”. ( refer to section
5.5.5
)
6
6
.
.
3
3
.
.
3
3
P
P
S
S
T
T
N
N
R
R
o
o
u
u
t
t
i
i
n
n
g
g
