AudioCodes Mediant 500 MSBR, User Manual

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User's Manual 514 Document #: LTRT-10375
Mediant 500 MSBR
c. (For Analog Interfaces Only) In the 'Alternative Routing Tone Duration' field,
configure the duration for which the device plays a tone to the Tel endpoint (for
analog interfaces) whenever an alternative route is used.
d. Enable the connectivity feature (see IP Destinations Connectivity Feature on
page 511).
27.4.3 Alternative Routing Based on SIP Responses
The device can perform alternative routing based on the received SIP response code (i.e.,
4xx, 5xx, 6xx, or 8xx). If you have configured the response code in the Reasons for Tel-to-
IP Alternative Routing table, the device attempts to re-route the call to an alternative
destination, if configured. You can configure up to 10 SIP response codes in the Reasons
for Tel-to-IP Alternative Routing table.
Typically, the device performs alternative routing when there is no response at all to an
INVITE message. This is done after a user-defined number of INVITE re-transmissions,
configured by the SIPMaxRtx parameter. In such a scenario, the device issues itself the
SIP response code 408 (Request Timeout). You can also configure the device to perform
alternative routing for the following proprietary response codes that are issued by the
device itself:

805 IP Profile Call Limit: The device generates this response code when Call
Admission Control (CAC) limits are exceeded for an IP Group. The CAC rules are
configured in the IP Profiles table (see Configuring IP Profiles on page 404). When
this occurs, the device sends a SIP 480 (Temporarily Unavailable) response to the
SIP entity.

806 Media Limits Exceeded: The device generates this response code when the call
is terminated due to crossed thresholds of QoE metrics such as MOS, packet delay,
and packet loss (configured in the Quality of Experience Profile table) and/or media
bandwidth (configured in the Bandwidth profile table). When this occurs, the device
sends a SIP 480 (Temporarily Unavailable) response to the SIP entity. This is
configured by 1) assigning an IP Group a QoE and/or Bandwidth profile that rejects
calls if the threshold is crossed, 2) configuring 806 in the Reasons for Tel-to-IP
Alternative Routing table and 3) configuring an alternative routing rule.
Note:

You can also enable the Busy Out feature, whereby the device can take specified
actions if all Proxy Sets of associated destination IP Groups of matching routing
rules in the Tel-to-IP Routing table do not respond to connectivity checks. For more
information, see the EnableBusyOut parameter.

If the AltRoutingTel2IPEnable parameter is enabled for the IP Connectivity feature
(see Alternative Routing Based on IP Connectivity on page 512), the Busy Out
feature does not function with the Proxy Set keep-alive mechanism (see below). To
use the Busy Out feature with the Proxy Set keep-alive mechanism (for IP Groups),
disable the AltRoutingTel2IPEnable parameter.

The device also plays a tone to the endpoint whenever an alternative route is used.
This tone is played for a user-defined time, configured by the
AltRoutingToneDuration parameter.
Depending on configuration, alternative routing is done using one of the following
configuration entities:

Tel-to-IP Routing Rules: Alternative routing rules can be configured for a specific
routing rule in the Tel-to-IP Routing table. If the destination of the "main" routing rule is
unavailable, the device searches the table for the next matching rule (e.g., destination
phone number), and if available attempts to re-route the call to the IP destination
configured for this alternative routing rule. For more information on configuring