Wikipedia
HYPERchannel, sometimes rendered Hyperchannel, was a local area networking system for mainframe computers, especially supercomputers, introduced by Network Systems Corporation in the 1970s. It ran at the then-fast speed of 50 mbits/second, performance that would not be matched by commodity hardware until the introduction of Fast Ethernet in 1995. HYPERchannel ran over very thick coax cable or fibre optic extensions and required adaptor hardware the size of a minicomputer. The networking protocol was entirely proprietary. Solutions for Control Data, IBM and Cray computers were their primary products, but a wide variety of support emerged in the 1980s, including DEC VAX and similar superminicomputers.
The introduction of 10 mbit/sec Ethernet in the 1980s was a major problem for the HYPERchannel product, one the company never clearly addressed. The company introduced products to allow HYPERchannel protocols to travel over Ethernet, and systems that allowed Ethernet-equipped computers to connect to HYPERchannel systems, as well as TCP/IP and other standard protocol support. However, these generally had the side-effect of further eroding the need for the product, other than raw performance, and it found itself pressed into an ever smaller niche that was eventually killed off by new systems with dramatically higher performance.