In an SAP IQ Multiplex grid, you have any number of nodes/machines that can handle and process user query requests. Often, the challenge becomes how to distribute the user connections across these nodes so that the compute power is fully leveraged without creating hot spots, or hot nodes. Historically, SAP IQ (and legacy Sybase) customers leverage network load balancers to distribute the workload. The attached document describes the various load balancing mechanisms and schemes at play from hardware and software approaches as well as using DNS for round robin distribution. It also describes the integration aspects and considerations that must be taken into account when deploying these load balancers with SAP IQ.
Below is a link to the full white paper.