Dialogic 6.2 Manuale Utente

Failover Based on Telephony Cause Codes

November 2009

233

Known Failures From Various Gateways

H.323 and SIP

Table 11

, the entries are divided between H.323 and SIP. In the

case of H.323, cause codes are sent by the gateway as values

corresponding to Q.931 error codes. These are returned unaltered by

BfvLineTerminateCall(). In the case of SIP, the gateway sends SIP

error codes which are then translated by BfvLineTerminateCall()

into Q.931 error codes before being returned.

Using cause codes to determine failover scenarios is complicated. In

most cases, the cause codes supplied by the gateway are

manufacturer-specific and depend on the protocol being used.

Applications needing specific information about a call failure can use

the cause codes reported by BfvLineTerminateCall() or

BfvCallWaitForComplete(). Note when the Bfv API function returns

BT_STATUS_TIMEOUT, the cause code will not be valid.

Table 11. Known Failover Cause Code Data

Scenario

SR140
Protocol

GnuGK

Alcatel

Avaya

SIP

Control

Cisco

2821

CCM6.01

CCM6.1

Quintum

IM1010

H.323

Unreachable IP

Address

H.323 1000

1000

Reachable IP address

with no SIP/H.323

responds

H.323 1000

1000

Gateway failure during

an active call by

disconnecting the

network cable on the

SR140

H.323 0, 16

0, 16

Gateway failure during

an active call by

disconnecting the

network cable on the

gateway

H.323 0