COBHAM Satcom EXPLORER 540 User & Integrator's Manual page 126

4.16.4 EXPLORER 540 operation in Cellular modem preferred
(PRISM) mode and External modem preferred (PRISM) mode
When the cellular modem is installed, the terminal offers simultaneous cellular and
BGAN IP-network connectivity, where each link receives an IP-address from the
corresponding Network Operator.
With the PRISM option, you can route all traffic to and from the EXPLORER 540 through
a multi-path tunnel between the terminal and a server, using cellular or BGAN
connectivity. Devices connected to the EXPLORER 540 will be immediately reachable
from server applications, regardless of the network technology (cellular or BGAN),
using the same IP address. Depending on server routing, devices attached to the
EXPLORER 540 will likewise have direct access to services on the server and beyond.
To set up PRISM you must install the PRISM server software from Cobham SATCOM,
configure the PRISM server and set up your EXPLORER 540 to communicate with this
server.
For details how to set up the EXPLORER 540 for PRISM, see To set up the connection
mode on page 4-15 and To set up PRISM on page 4-56.
Limitations in the PRISM connection modes
If your airtime network connection uses a private IP address and your ping interval is
set to more than 27 seconds, you may experience timeouts in the network, which will
break the PRISM IP tunnel.
To avoid this, contact your service provider to get a public IP address for the BGAN
connection, which will allow the BGAN ping interval to be longer. If this is not possible,
you must set the ping interval to less than 27 seconds.
98-148232-K Chapter 4: Configuration with web interface
PRISM/WAN switching
4-62