IBM mainframe IBM mainframes are large computer systems produced by IBM since 1952. During the 1960s and 1970s, IBM dominated the large computer market. Current mainframe computers in IBM's line of business computers are developments of the basic design of t ...

technology, a channel-to-channel adapter (CTCA) is a device that connects two

input/output In computing, input/output (I/O, or informally io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals ...

channels on (usually) two separate computer systems. The adapter allows one computer system to be treated as an input/output device by another. It is used "to link the processing units in a loosely coupled multiprocessing system. Virtual channel-to-channel adapters (VCTCA) are often used to communicate between two

virtual machine In computing, a virtual machine (VM) is the virtualization/ emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer. Their implementations may involve specialized har ...

s in the

z/VM z/VM is the current version in IBM's VM family of virtual machine operating systems. z/VM was first released in October 2000 and remains in active use and development . It is directly based on technology and concepts dating back to the 1960s, wi ...

operating system. The

Virtual Machine Communication Facility The IBM Virtual Machine Communication Facility (VMCF) is a feature of the VM/370 operating system introduced in Release 3 in 1976. It "provides a method of communication and data transfer between virtual machines operating under the same VM/370 sys ...

(VMCF), and later Inter User Communication Vehicle (IUCV) are now often used in place of VCTCAs because they provide a simpler interface and improved performance.

References

IBM mainframe technology {{comp-hardware-stub