Depending on the application that will run on the cluster, the choice of Dolphin Express Interconnect equipped machines differs.

Two nodes can be conneced directly using one or two CX4 cables to connect either onl y port 0 of each adapter, or both ports. This results in different avalaible bandwiths: a single cable has a link width of x4 ("times 4", 10Gbit/s bandwidth), while with two cables an effective link width of x8 ("times 8" for 20Gbit/s bandwitdh) is available. When using two cables, either cable can fail and come back again, with the link width going down to x4 and back to x8 accordingly.

Three nodes can be connected directly with a link width x4 between each pair of nodes. The three nodes then form a ring with one direct cable connection between each of them.

Up to 10 nodes can be connected to a DXS410 switch. This switch has 10 ports, and the can be used flexibly to connect to nodes with either a single cable for x4 link width, or two cabes for x8 link width. The different link width can be mixed at will as long as there are ports. available

Generally, nodes that are to be equipped with Dolphin Express interconnect adapters should be placed close to each other to keep cable lengths short. This reduces costs and allows for better routing of the cables.

Dolphin Express DX supports both copper and fiber optic cables. The maximum cable length is 10 meter for copper cables (CX4) and 100 meter for fiber. Please ask your Dolphin sales representative for details.

Once you have decided on the physical node placement, the cables should be ordered in the according lengths. The Dolphin sales representative will assist you in selecting the right cable lengths.