Hyper Transports

Hyper Transport technology is a very fast, low latency, point-to-point link used for inter-connecting integrated circuits on board. Hyper Transport, previously codenamed as Lightning Data Transport (LDT), provides the bandwidth and flexibility critical for today's networking and computing platforms while retaining the fundamental programming model of PCI. Hyper Transport was invented by AMD and perfected with the help of several partners throughout the industry.Hyper Transport was designed to support both CPU-to-CPU communications as well as CPU-to-I/O transfers, thus, it features very low latency. It provides up to 22.4 Gigabyte/second aggregate CPU to I/O or CPU to CPU bandwidth in a highly efficient chip-to-chip technology that replaces existing complex multi-level buses .Using enhanced 1.2 volt LVDS signaling reduces signal noise, using non-multiplexed lines cuts down on signal activity and using dual-data rate clocks lowers clock rates while increasing data throughput. . It employs a packet-based data protocol to eliminate many sideband (control and command) signals and supports asymmetric, variable width data paths. New specifications are backward compatible with previous generations of specification, extending the investment made in one generation of Hyper Transport-enabled device to future generations. Hyper Transport devices are PCI software compatible, thus they require little or no software overhead. The technology targets networking, telecommunications, computers and embedded systems and any application where high speed, low latency and scalability are necessary.