Carrier Access SNMP manual BRFXS/DPO Applications, Dpo

BRFXS/DPO Applications

Note: During a two-way call, the CPE -loop battery is reversed. To disconnect the call either the CPE loop current ceases or the network sends A/B bits = 0/0. The reversed state of the CPE loop, however, will be maintained until the network terminates (releases) the call.

9.4 BRFXS/DPO Applications

As explained above, the two major applications for the BRFXS/DPO card are FXS with battery reversal “wink” to signal a PBX timer to start billing a call and Dial Pulse Origination (DPO) for transport of Direct Inward Dialing (DID) lines. Refer to Figure 9-1and Figure 9-2for pictorial repre- sentations of these two applications.

PBX

FXS loop-start lines

Battery Reversal to PBX

DPO*

T1

Optional cadenced ringing voltage applied to CPE during incoming call

Optional cadenced ringback tone to T1 during incoming calls

Figure 9-1: Battery Reversal FXS Loop-Start for Starting PBX Billing Timer

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