15.4 Creation of an ISDN trunk
If SwyxServer and the SwyxWare Administration are already installed, then following the insertion of the ISDN card and the creation of an ISDN trunk group you can set up an ISDN trunk.
In the standard installation of the SwyxServer software, the corresponding service SwyxGate which is responsible for the link-up of ISDN lines is automatically installed. During the installation of an ISDN trunk you give the name of the computer on which the SwyxGate service is installed. This service is then used by the ISDN trunk.
This is how you create an ISDN Trunk
1 Open the SwyxWare Administration and choose the SwyxServer.
2 In the left side of the SwyxWare Administration window, click with the right mouse button on "Trunks" and select the entry "Add Trunk…" in the context menu.
3 An "Add new Trunk Wizard" opens up.
Click on "Next>".
4 Trunk name:
Enter a name and a short description for the new trunk here.
Click on "Next>".
5 Selection of a trunk group:
Select the trunk group here to which this trunk should be assigned.
General settings such as routings, rights and location-specific parameters are specified in the trunk group. You can use "New Trunk Group..." to create a new trunk group, and then continue with the creation of a trunk.
6 Numbers:
Click on "Next >".
7 Codecs:
With the help of the Codec you select how the voice is compressed for transmission. The following options are available:
If the Codec priority "Prefer Quality" is selected, the Codecs are provided in the sequence G.722, G.711a, G.711µ, G.729 and Fax over IP. Specify the filter(s) you want. The Codec G.722 is deactivated by default, because it would only be supported up to the ISDN gateway.
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Voice, high bandwidth (G.711a, G.711µ)
The voice data is slightly compressed. This keeps the packet delay time in the LAN (Local Area Network) to a minimum. A voice connection requires approximately 64kbits/s.
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Voice, low bandwidth (G.729)
High compression. A voice connection requires approximately 24kbits/s.
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Fax
In this case, the special fax protocol T.38 is used, which takes the set-up of the IP network into consideration. A fax connection using T.38 requires approximately 20kbits/s.
If the Codec priority "Prefer low bandwidth" is selected, the Codecs sequence changes to G.729, G.722, G.711a, G.711µ, Fax over IP. The Codec G.722 is deactivated by default, because it would only be supported up to the ISDN gateway. The aim here is to use as little bandwidth as possible. Here too, specify the filter(s).
8 Click on "Next>".
Both voice compressions can be activated for a voice connection. In this case the SwyxServer decides which compression is applied.
9 Number of ISDN channels:
Give the number of lines that are served by this trunk.
10 Computer name:
Give the name of the computer in which the card has been inserted. The SwyxGate service must also be installed on this computer, before this trunk can be used. Please use a WINS or the DNS name as the computer name. Alternatively you can also give the IP address of the computer directly. Do not enter ’localhost’ here.
11 Select ISDN ports:/
Select the ISDN card from the list. According to the ISDN card, the available ports are displayed. Select the port to be used. The selection of the port is visualized with the help of a blinking LED on the ISDN card. This lets you see easily which port the ISDN connection cable must be connected to.
12 Click "Finish".
The new Trunk is created, and is available for further configuration.