Myrinet is a cost-effective, high-performance, packet-communication and switching technology that is widely used to interconnect clusters of workstations, PCs, servers, or single-board computers. Clusters provide an economical way of achieving:

• high performance, by distributing demanding computations across an array of cost-effective hosts. For "tightly coupled" distributed computations, the interconnect must provide high-data-rate and low-latency communication between host processes.
• high availability, by allowing a computation to proceed with a subset of the hosts. The interconnect should be capable of detecting and isolating faults, and of using alternative communication paths.

Conventional networks such as Ethernet can be used to build clusters, but do not provide the performance or features required for high-performance or high-availability clustering. Characteristics that distinguish Myrinet from other networks include:

• Full-duplex 2+2 Gigabit/second links, switch ports, and interface ports.
• Flow control, error control, and "heartbeat" continuity monitoring on every link.
• Low-latency, cut-through, crossbar switches, with monitoring for high-availability applications.
• Myrinet networks can scale to tens of thousands of hosts, with network-bisection data rates in Terabits per second, and can also provide alternative communication paths between hosts.
• Host interfaces that execute a control program to interact directly with host processes ("OS bypass") for low-latency communication, and directly with the network to send, receive, and buffer packets.