21: Automatic operator selection
_______________________________________________________________________________________________________
_______________________________________________________________________________________________________
© Virtual Access 2018
GW2020 Series User Manual
Issue: 2.1
Page 186 of 423
21
Automatic operator selection
This section describes how to configure and operate the Automatic Operator Selection
feature of a Virtual Access router.
When the roaming SIM is connected, the radio module has the ability to scan available
networks. The router, using mobile and multi-WAN packages, finds available networks to
create and sort interfaces according to their signal strength. These interfaces are used
for failover purposes.
21.1
Configuration package used
Package
Sections
Multiwan
General, interfaces
Mobile
Main, Template interface
Network
2G/3G/4G interface
21.2
Configuring automatic operator selection via the web interface
While the router boots up it checks for mobile networks. Based on available networks,
the router creates interfaces and the multiwan package is used to run failover between
interfaces. Typically these auto-generated interfaces are sorted by signal strength.
Details for these interfaces are provided in the mobile package. When you have created
the interfaces, Multi-WAN manages the operation of primary (predefined) and failover
(auto created) interfaces.
Multi-WAN periodically does a health check on the active interface. A health check
comprises of a configurable combination of the following:
•
interface state
•
pings to an ICMP target
•
signal level checks using signal threshold, RSCP threshold and ECIO threshold
option values
A fail for any of the above health checks results in an overall fail. After a configurable
number of health check failures, multiwan will move to the next highest priority
interface. Multi-WAN will optionally stop the failed interface and start the new interface,
if required.
In some circumstances, particulary in mobile environments, it is desirable for a primary
interface to be used whenever possible. In this instance, if the active interface is a not
the primary interface, multiwan will perform a health check on the primary interface
after a configurable period. If the health checks pass for the configured number of
recovery health checks then the primary interface will be used.