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IEEE Standard 1355-1995, IEC 14575, or ISO 14575 is a data communications standard for Heterogeneous Interconnect (HIC). IEC 14575 is a low-cost, low latency, scalable serial interconnection system, originally intended for communication between large numbers of inexpensive computers. IEC 14575 lacks many of the complexities of other data networks. The standard defined several different types of transmission media (including wires and optic fiber), to address different applications. Since the high-level network logic is compatible, inexpensive electronic adapters are possible. IEEE 1355 is often used in scientific laboratories. Promoters include large laboratories, such as CERN, and scientific agencies. For example, the ESA advocates a derivative standard called SpaceWire. ==Goals== The protocol was designed for a simple, low cost switched network made of point-to-point links. This network sends variable length data packets reliably at high speed. It routes the packets using wormhole routing. Unlike Token Ring or other types of local area networks (LANs) with comparable specifications, IEEE 1355 scales beyond a thousand nodes requiring higher transmission speeds. The network is designed to carry traffic from other types of networks, notably Internet Protocol and Asynchronous Transfer Mode (ATM), but does not depend on other protocols for data transfers or switching. In this, it resembles Multiprotocol Label Switching (MPLS). IEEE 1355 had goals like Futurebus and its derivatives Scalable Coherent Interface (SCI), and InfiniBand. The packet routing system of IEEE 1355 is also similar to VPLS, and uses a packet labeling scheme similar to MPLS. IEEE 1355 achieves its design goals with relatively simple digital electronics and very little software. This simplicity is valued by many engineers and scientists. Paul Walker (see links ) said that when implemented in an FPGA, the standard takes about a third the hardware resources of a UART (a standard serial port), and gives one hundred times the data transmission capacity, while implementing a full switching network and being easier to program. Historically, IEEE 1355 derived from the asynchronous serial networks developed for the Transputer model T9000 on-chip serial data interfaces.〔 The Transputer was a microprocessor developed to inexpensively implement parallel computation. IEEE 1355 resulted from an attempt to preserve the Transputer's unusually simple data network. This data strobe encoding scheme makes the links self-clocking, able to adapt automatically to different speeds. It was patented by Inmos under U.K. patent number 9011700.3, claim 16 (DS-Link bit-level encoding), and in 1991 under US patent 5341371,〔 〕 claim 16. The patent may still be in force. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「IEEE 1355」の詳細全文を読む スポンサード リンク
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