Merge pull request #10878 from teddygyabaah/patch-24

Update direct-routing-trunk-failover-on-outbound-call.md

Teams/direct-routing-trunk-failover-on-outbound-call.md

@@ -33,7 +33,8 @@ For example, a connection might fail if an administrator limits access to the SB
 
 ## Failover of specific SIP codes received from the Session Border Controller (SBC)
 
-If Direct Routing receives any 4xx or 6xx SIP error codes in response to an outgoing Invite, the call is considered completed by default. Outgoing means a call from a Teams client to the Public Switched Telephone Network (PSTN) with the following traffic flow: Teams Client -> Direct Routing -> SBC -> Telephony network.
+
+When a call from a Teams client to the Public Switched Telephone Network (PSTN) is made with the following traffic flow: Teams Client -> Direct Routing -> SBC -> Telephony network, any non-2xx final response code from the SBC can be configured to be retried on another SBC in the voice routing policy. Note that failover will only happen in the absence of non-100 provisional responses from the SBC, to prevent double ringing telephony network.
 
 The list of SIP Codes can be found in [Session Initiation Protocol (SIP) RFC](https://tools.ietf.org/html/rfc3261).