Example: Balancing traffic according to link capacity

To manage ISP connections having very different bandwidths, you configure an Outbound Multi-Link element and select ratio load balancing.

Company B has three ISP connections that have different bandwidths:

• ISP A 20 Mbit/s
• ISP B 10 Mbit/s
• ISP C 4 Mbit/s

The administrators want the traffic to be divided between the NetLinks according to the ratio of their relative bandwidths. This means that ISP A handles twice as much traffic as ISP B and five times as much traffic as ISP C. The administrators have already created and configured NetLink elements to represent each ISP connection, so now they:

1. Combine the NetLinks for each ISP connection into an Outbound Multi-Link element and select the Ratio load-balancing method.
2. Define the following NAT rule for outbound load balancing in the Firewall Policy:

   Source	Destination	Service	NAT
   ANY	ANY	ANY	Dynamic load balancing: Multi-Link Element