15.1.3.2. CICA Connectivity to OS4K 
The CSTA protocol used by OpenScape Mobile Pro Client is a plaintext
protocol that does not support encryption. The Integrated VPN feature
is a security enhancement, which creates a Virtual Private Network to
encrypt network traffic and provides connectivity between remote components
of an OpenScape 4000 (OS4K) system.
INFO:
For detailed information how to setup the Integrated VPN service,
please refer to OpenScape 4000 V8 - Platform Administration (Portal),
Administrator Documentation, chapter Integrated VPN Service.
If enabled this feature will set-up a VPN network between OS4K Host
system and SoftGates, which encrypts any traffic between the vHG boards
and CSTA. This includes the CICA connectivity traffic.
If the Integrated VPN feature setup fails, the CICA traffic is routed
via IPDA LAN directly (in plaintext).