Dear Sirs

I am having a database timeout problem when I leave(idle) my PowerBuilder application around 30-60 mins, it is connected to a remote sybase database sever.

Network: Two remote offices, connected w/ Cisco VPN IPSec always on Site-to-Site connection.

Symptoms: When I leave my application around 30-60 mins, my application cannot query the sybase database and receives this error message:
"Select error: ct_cmd_alloc(): user api layer: external error: The connection has been marked dead."

What is the main reason of this timeout? Network/Sybase/PowerBuilder??

I am not the DBA, but I am looking for an advise here to check w/ our DBA.

I can only check the VPN network devices and cannot find anything I need to adjust. Becoz many timeout connection items are set to no timeout already...

Please advise w/ thanks!!!