A non-IBM mainframe that runs IBM mainframe operating systems and applications. In the late 1960s, RCA's computer division produced the Spectra 70, the first line of machines compatible with IBM's System/360. Later, Amdahl, National Semiconductor (marketed through Itel) and Hitachi entered this segment. Today, IBM-compatible mainframes are no longer manufactured. Although servers from HP, Sun and others offer mainframe-like features, IBM is the only company making IBM mainframes. See
HDS and
Amdahl.
Hitachi's Skyline
Over the years, several companies offered products that ran IBM mainframe operating systems. This Skyline model from Hitachi could be configured with up to 512 channels and 16 ports into memory, providing enormous transaction processing throughput. (Image courtesy of Hitachi Data Systems.)