AudioCodes MP-11x User Manual page 270

Table 23-5: Alternative Routing based on SIP Response Code Example
Main Route
Alternative Route #1
Alternative Route #2

Proxy Sets: Proxy Sets are used for Server-type IP Groups (e.g., an IP PBX) and
define the actual IP destination (IP address or FQDN) of the server. As you can define
up to five IP destinations per Proxy Set, the device supports proxy redundancy, which
works together with the alternative routing feature. If the destination of a routing rule in
the Outbound IP Routing table is an IP Group, the device routes the call to the IP
destination configured for the Proxy Set associated with the IP Group. If the first IP
destination of the Proxy Set is unavailable, the device attempts to re-route the call to
the next proxy destination, and so on until an available IP destination is located. To
enable the Proxy Redundancy feature, set the IsProxyHotSwap parameter to 1 (per
Proxy Set) and set the EnableProxyKeepAlive to 1.
When the Proxy Redundancy feature is enabled, the device continually monitors the
connection with the proxies by using keep-alive messages (SIP OPTIONS). The
device sends these messages every user-defined interval (ProxyKeepAliveTime
parameter). Any response from the proxy, either success (200 OK) or failure (4xx
response) is considered as if the proxy is communicating. If there is no response from
the first (primary) proxy after a user-defined number of re-transmissions (re-INVITEs)
configured using the HotSwapRtx parameter, the device attempts to communicate
(using the same INVITE) with the next configured (redundant) proxy in the list, and so
on until an available redundant proxy is located. The device's behavior can then be
one of the following, depending on the ProxyRedundancyMode parameter setting:
•
The device continues operating with the redundant proxy (now active) until the
next failure occurs, after which it switches to the next redundant proxy. This is
referred to as Parking mode.
•
The device always attempts to operate with the primary proxy. In other words, it
switches back to the primary proxy whenever it's available again. This is referred
to as Homing mode.
If none of the proxy servers respond, the device goes over the list again.
The steps for configuring alternative Tel-to-IP routing based on SIP response codes are
summarized below.

To configure alternative Tel-to-IP routing based on SIP response codes:
1. Enable alternative routing based on SIP responses, by setting the 'Redundant Routing
Mode' parameter to one of the following:
•
Routing Table for using the Outbound IP Routing table for alternative routing.
•
Proxy for using the Proxy Set redundancy feature for alternative routing.
2. If you are using the Outbound IP Routing table, configure alternative routing rules with
identical call matching characteristics, but with different IP destinations. If you are
using the Proxy Set, configure redundant proxies.
User's Manual
Destination
IP Destination
Phone Prefix
40 10.33.45.68
40 10.33.45.70
40 10.33.45.72
SIP Response
408 Request
Timeout
486 Busy Here
200 OK
270
MP-11x & MP-124
Rule Used?
No
No
Yes
Document #: LTRT-65432