Alternative Routing Based On Ip Connectivity - AudioCodes Mediant 800 User Manual

CHAPTER 25 Routing
● SIP OPTIONS: The device sends "keep-alive" SIP OPTIONS messages to the IP
destination. If the device receives a SIP 200 OK in response, it considers the destination
as available. If the destination does not respond to the OPTIONS message, then it is
considered unavailable. You can configure the time interval for sending these OPTIONS
messages, using the 'Alt Routing Tel to IP Keep Alive Time' parameter.
These parameters are configured in the Routing Settings page (Setup menu > Signaling &
Media tab > Gateway folder > Routing > Routing Settings), as shown below:
■ Quality of Service (QoS): You can enable the device to check the QoS of IP destinations.
The device measures the QoS according to RTCP statistics of previously established calls
with the IP destination. The RTCP includes packet delay (in milliseconds) and packet loss (in
percentage). If these measured statistics exceed a user-defined threshold, the destination is
considered unavailable. Note that if call statistics is not received within two minutes, the QoS
data is reset. These thresholds are configured using the following parameters:
● 'Max Allowed Packet Loss for Alt Routing' (IPConnQoSMaxAllowedPL): defines the
threshold value for packet loss after which the IP destination is considered unavailable.
● 'Max Allowed Delay for Alt Routing' (IPConnQoSMaxAllowedDelay): defines the threshold
value for packet delay after which the IP destination is considered unavailable
These parameters are configured in the Routing Settings page (Setup menu > Signaling &
Media tab > Gateway folder > Routing > Routing Settings), as shown below:
■ DNS Resolution: When a host name (FQDN) is used (instead of an IP address) for the IP
destination, it is resolved into an IP address by a DNS server. The device checks network
connectivity and QoS of the resolved IP address. If the DNS host name is unresolved, the
device considers the connectivity of the IP destination as unavailable.
You can view the connectivity status of IP destinations in the following Web interface pages:
■ Tel-to-IP Routing table: The connectivity status of the IP destination per routing rule is
displayed in the 'Status' column. For more information, see
Rules.
■ IP Connectivity: This page displays a more informative connectivity status of the IP
destinations used in Tel-to-IP routing rules in the Tel-to-IP Routing table. For viewing this page,
see Viewing IP

Alternative Routing Based on IP Connectivity

You can configure the device to route Tel-to-IP calls to an alternative IP destination when the
connectivity state of an IP destination is unavailable. The alternative routing rules are configured in
the Tel-to-IP 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 Tel-to-IP routing rules in the Tel-to-IP Routing table, see
Rules.
Connectivity.
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Mediant 800 Gateway & E-SBC | User's Manual
Configuring Tel-to-IP Routing
Configuring Tel-to-IP Routing