Using Cellular Modems In A Wireless Wan (Wwan) - Digi TX54 User Manual

Interfaces

Using cellular modems in a Wireless WAN (WWAN)

The TX54 supports either one or two cellular modems, depending on the model. The modems are
named:
Single-cellular models:
n
WWAN cellular modem or WWAN1 cellular modem
l
Dual-cellular models:
n
WWAN1 cellular modem
l
WWAN2 cellular modem.
l
These devices are included in one or two preconfigured Wireless WANs, WWAN or WWAN1, and
WWAN2.
Each cellular modem can have only one active SIM slot at any one time. For example, WWAN1 cellular
modem can have either SIM1 or SIM2 up at one time.
Typically, you configure SIM1 of the cellular modem as the primary cellular interface, and SIM2 as the
backup cellular interface. In this way, if the TX54 device cannot connect to the network using SIM1, it
automatically fails over to SIM2. TX54 devices automatically use the correct cellular module firmware
for each carrier when switching SIMs.
The dual-cellular variants of the TX54 device can have two cellular interfaces up at one time—one for
each modem. Typically, an administrator would route traffic to different destinations over a specific
cellular interface.
Configure cellular modems
Configuring the TX54's cellular modems involves configuring the following items:
Required configuration items
Enable the cellular modem.
n
Cellular modems are enabled by default.
Determine the SIM slot that will be used when connecting to the cellular network.
n
Configure the maximum number of interfaces that can use the modem.
n
Enable carrier switching, which allows the modem to automatically match the carrier for the
n
active SIM.
Carrier switching is enabled by default.
Configure the access technology.
n
Determine which cellular antennas to use.
n
Additional configuration items
If Active SIM slot is set to Any, determine the preferred SIM slot.
n
In the event of a failover to a non-preferred SIM, or if manual SIM switching is used to switch to
a non-preferred SIM, the modem will attempt to reconnect to the SIM in the preferred SIM slot.
To configure the modem:

WebUI
TX54 User Guide
Wide Area Networks (WANs)
92