System information

• Ensure that if the Line 1 key on station1 is pressed a call is sent to the sta
tion1_line1 extension, and so on.
Key System Example with SIP Trunks
This example is intended to be identical in functionality to the previous example. The
difference is that instead of using analog lines as trunks, we will use a connection to a
SIP provider that will terminate the calls to the PSTN. For more information on setting
up Asterisk to connect to a SIP provider, see Chapter 7.
sla.conf
The sla.conf file for this scenario is a bit tricky.
‡
You might expect to see the device line
in the trunk configuration have a SIP channel listed, but instead we’re going to use a
Local channel. This will allow us to use some additional dialplan logic for call pro-
cessing. The purpose of the Local channel will become clearer in the next section, when
the dialplan example is discussed. Here are the trunk configurations:
[line1]
type = trunk
device = Local/disa@line1_outbound
[line2]
type = trunk
device = Local/disa@line2_outbound
The station configuration is identical to the last example, so let’s get right to it:
[station](!)
type = trunk
trunk = line1
trunk = line2
[station1](station)
device = SIP/station1
[station2](station)
device = SIP/station2
[station3](station)
device = SIP/station3
[station4](station)
device = SIP/station4
‡ Read: a hack.
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