AudioCodes E-SBC User Manual

CHAPTER25 Routing
Mediant 1000 Gateway & E-SBC | User's Manual
The following procedure describes how to configure alternative Tel-to-IP routing to the PSTN.
➢ To configure alternative Tel-to-IP routing to the PSTN:
1. In the Tel-to-IP Routing table (see Configuring Tel-to-IP Routing Rules), configure an
alternative routing rule with the same call matching characteristics (e.g., phone number
destination) as the "main" routing rule, but where the destination is the IP address of the device
itself.
2. In the IP-to-Tel Routing table (see Configuring IP-to-Tel Routing Rules), configure an IP-to-Tel
routing rule to route calls received from the device (i.e., its IP address) to a specific Trunk
Group connected to the PSTN. This configuration is necessary as the re-routed call is now
considered an IP-to-Tel call.
The PSTN Fallback feature is applicable only to digital interfaces.
Alternative Routing for IP-to-Tel Calls
This section describes configuration for alternative IP-to-Tel call routing.
Alternative Routing to Trunk upon Q.931 Call Release Cause
Code
You can configure up to 10 ISDN Q.931 release cause codes. If the device receives a configured
release cause code from the Tel side, it routes the IP-to-Tel call to an alternative Trunk Group, if
configured.
Alternative IP-to-Tel routing rules are configured in the IP-to-Tel Routing table. These rules must be
configured anywhere below the "main" routing rule and with identical matching characteristics (e.g.,
destination prefix number) to the "main" routing rule. The device uses the first alternative route that
is available. For more information on configuring alternative IP-to-Tel routing rules in the IP-to-Tel
Routing table, see Configuring IP-to-Tel Routing Rules.
A release cause code indicates that the IP-to-Tel call has been rejected or disconnected on the Tel
side. The release cause codes are configured in the Reasons for IP-to-Tel Alternative Routing
table. For example, you can configure alternative IP-to-Tel routing for scenarios where the initial Tel
destination is busy and a Q.931 Cause Code No. 17 is received (or for other call releases that issue
the default Cause Code No. 3).
You can configure a default release cause code that the device issues itself upon the following
scenarios:
■ The device initiates a call release whose cause is unknown.
■ No free channels (i.e., busy) in the Trunk Group.
■ No appropriate routing rule located in the IP-to-Tel Routing table.
■ Phone number is not located in the IP-to-Tel Routing table.
The default release code is Cause Code No. 3 (No Route to Destination). You can change the
default code as follows:
➢ To change the default Q.931 release code:
1. Open the Gateway Advanced Settings page (Setup menu > Signaling & Media tab >
Gateway folder > Gateway Advanced Settings).
2. In the 'Default Release Cause' field, enter the release cause code:
3. Click Apply.
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AudioCodes E-SBC Specifications

General

Brand	AudioCodes
Model	E-SBC
Category	Gateway
Language	English