Problems with FXS disconnect

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Jul 27th, 2009
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I have 186x series router with build-in four FXS ports. When I call FXS port (SCCP IP Phone through H.323), I get connected to GSM GW; when I disconnect by IPPhone the line is still busy



voice-port 0/0/3

no supervisory disconnect lcfo

no battery-reversal

signal groundStart

input gain 6

compand-type a-law

no comfort-noise

cptone PL



dial-peer voice 600 pots

max-conn 1

destination-pattern 0048.........

port 0/0/3

forward-digits all


Ani ideas how to say to GSM GW that call is cleared?

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paolo bevilacqua Mon, 07/27/2009 - 14:34
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To begin with, should be signal loopstart.

Then check GSM box documentation for what disconnect supervision method it can use.

Note these connection are better done with ISDN BRI or SIP. Analog is always source of trouble.

m.laskowski Mon, 07/27/2009 - 23:35
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I tried loopstart earlier and the problem still exists

It's a Nokia GSM adapter - the default rule for disconnect supervision in this adapter is monotoring silence. Any idea how to apply such settings on Cisco router ?

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paolo bevilacqua Tue, 07/28/2009 - 07:35
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Silence is silence, no special config is required.

I have a client with old Nokia adapters and they work acceptably. They are of the type with both FXS and FXO ports.

m.laskowski Wed, 07/29/2009 - 00:06
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It is old Nokia adapter - can You paste part of config ? (I'm interested in voice-port part) Thanks


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