Figure 103 Spillover Algorithm Example; Figure 104 Load Balancing: Spillover; Table 40 Load Balancing: Spillover - ZyXEL Communications 5 Series User Manual

In cases where the primary WAN interface uses an unlimited access Internet connection and
the secondary WAN uses a per-use timed access plan, the ZyWALL will only use the
secondary WAN interface when the traffic load reaches the upper threshold on the primary
WAN interface. This allows you to fully utilize the bandwidth of the primary WAN interface
while avoiding overloading it and reducing Internet connection fees at the same time.
In the following example figure, the upper threshold of the primary WAN interface is set to
800K. The ZyWALL sends network traffic of a new session that exceeds this limit to the
secondary WAN interface.

Figure 103 Spillover Algorithm Example

To load balance using the spillover method, select Spillover in the Load Balancing
Algorithm field.
Configure the Route Priority metrics in the WAN General screen to determine the primary
and secondary WANs. By default, WAN 1 is the primary WAN and WAN 2 is the secondary
WAN.

Figure 104 Load Balancing: Spillover

The following table describes the related fields in this screen.

Table 40 Load Balancing: Spillover

LABEL
Active/Active
Mode
Load Balancing
Algorithm
ZyWALL 5/35/70 Series User's Guide
DESCRIPTION
Select Active/Active Mode and set the related fields to enable load balancing on
the ZyWALL.
Set the load balancing method to Spillover.
Chapter 9 WAN Screens
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