Network: eSpace 7810 (IP phone)----New Rock SBC----U1930----PSTN
Version: eSpace U1930 V100R001C01SPC600
When a user uses an IP phone to make intra-office calls, some calls cannot be connected. When the user invites a third party to join a three-party call, the call is automatically disconnected after about 10 minutes.
Step 1 Set the reregistration time on IP phones to the same value as that configured on the SBC.
If the number of IP phones is small, set the registration timeout time on each IP phone to 600s.
If there are a large number of IP phones, run the config modify sip parameter maxregexpires 10 command in the eSpace U1930 configuration mode to change the registration timeout interval to 10 minutes, allowing more registration retrial attempts for phones that failed to be registered.
If you modify the maxregexpires parameter on the eSpace U1930, the parameter value is delivered to IP phones when they reregister with the eSpace U1930 the next time.
Step 2 If the fault persists, contact the service provider.
The default reregistration time of eSpace 7800 series IP phones is 3600s. The session life time on early versions of the New Rock SBC is 600s. In some circumstances, the SBC session may become invalid, resulting in random call faults or call disconnections.