The sq interface provides access to a Ethernet network via the SEEQ 8003 and 80c03 (aka SGI EDLC) chip sets. DMA is provided by hpc(4).
The sq is found in the Personal Iris 4D/3x, Indigo, Indy, Challenge S, Challenge M, and Indigo2 machines, as well as the SGI E++ GIO32bis Ethernet adapter.