The Cluster Edition supports only the UDP network protocol for private interconnects; do not use the TCP network protocol.
A private interconnect is a physical connection that allows internode communication, and is an essential component of a shared-disk cluster installation. A private interconnect can be a simple crossover cable with Ethernet, or it can be a complex solution. When you configure more than two nodes, a switch that enables high-speed communication between the nodes in the cluster is required.
To handle the amount of traffic created by contention, use scalable interconnect technology to connect nodes. The amount of traffic is directly proportional to the number of interinstance updates and transfers. SAP recommends that you implement the highest bandwidth, lowest-latency interconnect available.
The Cluster Edition supports the current standards for interconnects. SAP recommends that you research the available interconnects to find the one that works best for your site.