Three-Node Networks - Sun Microsystems Sun HPC 3.0 Manual

Figure 1–2 Two-Node SCI Interconnection, Without Striping
If you expect to add a node to a two-node network at a later time, you may want to
connect the two nodes through a switch now, even though the switch is not needed.
This would simplify the process of adding a third node later on. The chief
disadvantage to using a switch in a two-node network is the latency it adds to the
communication path between the nodes.
This alternate connection scheme is discussed further in "Connecting SCI Adapter
Cards in a Two-Node Network" on page 12.

Three-Node Networks

Figure 1–3 shows examples of how three Sun HPC nodes can be connected to an SCI
network, in both unstriped and striped modes.
Sun HPC 3.0 SCI Guide ♦ June 1999, Revision A
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