User`s guide

Chapter 5 WAN & 3G Cellular Screens
LAN-Cell 2 User’s Guide
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5.2.1.4 Weighted Round Robin
Round Robin routes traffic on a rotating basis and is activated only when a WAN interface has
more traffic than the configured available bandwidth. On the LAN-Cell with two WAN
interfaces, an amount of traffic is sent through the first interface. The second interface is also
given an equal amount of traffic, and then the same amount of traffic is sent through the first
interface again; and so on. This works in a looping fashion until there is no outgoing traffic.
Similar to the Round Robin (RR) algorithm, the Weighted Round Robin (WRR) algorithm sets
the LAN-Cell to send traffic through each WAN interface in turn. In addition, the WAN
interfaces are assigned weights. An interface with a larger weight gets more of the traffic than
an interface with a smaller weight.
This algorithm is best suited for situations when the bandwidths set for the two WAN
interfaces are different.
For example, in the figure below, the configured available bandwidth of WAN is 1M and
Cellular is 512K. You can set the LAN-Cell to distribute the network traffic between the two
interfaces by setting the weight of WAN and Cellular to 2 and 1 respectively. The LAN-Cell
assigns the traffic of two sessions to WAN for every one session's traffic assigned to Cellular.
Figure 51 Weighted Round Robin Algorithm Example
To load balance using the weighted round robin method, select Weighted Round Robin in the
Load Balancing Algorithm field.
Available
Inbound
Bandwidth
This field is applicable when you select Outbound + Inbound or Inbound Only in
the Load Balancing Index(es) field.
Specify the inbound (or downstream) bandwidth (in kilo bites per second) for the
interface. This should be the actual downstream bandwidth that your ISP provides.
Available
Outbound
Bandwidth
This field is applicable when you select Outbound + Inbound or Outbound Only in
the Load Balancing Index(es) field.
Specify the outbound (or upstream) bandwidth (in kilo bites per second) for the
interface. This should be the actual upstream bandwidth that your ISP provides.
Table 22 Load Balancing: Least Load First (continued)
LABEL DESCRIPTION