The first group is intended for scale-up symmetric multiprocessing (SMP), and consists of the CX1000-SM and CX1000-SC nodes.
The second group is meant for scale-out cluster computing, and consists of the CX1000 Blade Enclosure, and the CX1000-HN, CX1000-C and CX1000-G nodes.
The CX1000 line sits between Cray's entry-level CX-1 Personal Supercomputer range and Cray's high-end XT-series supercomputers.
[1] The CX1000-SM and CX1000-SC nodes can be used for cluster computing, but they are designed for scale-up Symmetric Multi-Processing (SMP).
The CX1000-SM and CX1000-SC nodes, when used for SMP, are connected by a cache-coherency interconnect which is a built-in subassembly of the CX1000-SM and CX1000-SC nodes, rather than a standalone device, and is called the Drawer Interconnect Switch in Cray literature.