- Fiber distributed data interface
Fiber distributed data interface (FDDI) provides a standard for
data transmissionin a local area networkthat can extend in range up to 200 kilometers (124 miles). Although FDDI protocol is a token ring network, it does not use the IEEE 802.5 token ringprotocol as its basis; instead, its protocol is derived from the IEEE 802.4 token bus"timed token" protocol. In addition to covering large geographical areas, FDDI local area networks can support thousands of users. As a standard underlying medium it uses optical fiber(though it can use coppercable, in which case one can refer to CDDI). FDDI uses a dual-attached, counter-rotating token ring topology.
FDDI, as a product of
American National Standards InstituteX3T9.5 (now X3T12), conforms to the Open Systems Interconnection (OSI) model of functional layering of LANs using other protocols. FDDI-II, a version of FDDI, adds the capability to add circuit-switched service to the network so that it can also handle voice and videosignals. Work has started to connect FDDI networks to the developing Synchronous Optical Network SONET.
A FDDI network contains two token rings, one for possible backup in case the primary ring fails. The primary ring offers up to 100 Mbit/s capacity. When a network has no requirement for the secondary ring to do backup, it can also carry data, extending capacity to 200 Mbit/s. The single ring can extend the maximum distance; a dual ring can extend 100 km (62 miles). FDDI has a larger maximum-frame size than standard 100 Mbit/s
Ethernet, allowing better throughput.
Designers normally construct FDDI rings in the form of a "dual ring of trees" (see
network topology). A small number of devices (typically infrastructure devices such as routers and concentrators rather than host computers) connect to both rings - hence the term "dual-attached". Host computers then connect as single-attached devices to the routers or concentrators. The dual ring in its most degenerate form simply collapses into a single device. Typically, a computer-room contains the whole dual ring, although some implementations have deployed FDDI as a Metropolitan area network.
FDDI requires this network topology because the dual ring actually passes through each connected device and requires each such device to remain continuously operational (the standard actually allows for optical bypasses, but network engineers consider these unreliable and error-prone). Devices such as workstations and minicomputers that might not come under the control of the network managers are not suitable for connection to the dual ring.
As an alternative to using a dual-attached connection, a workstation can obtain the same degree of resilience through a dual-homed connection made simultaneously to two separate devices in the same FDDI ring. One of the connections becomes active while the other one is automatically blocked. If the first connection fails, the backup link takes over with no perceptible delay.
Due to their speed, cost and ubiquity,
fast Ethernetand (since 1998) Gigabit Ethernethave largely made FDDI redundant.
FDDI standards include:
* ANSI X3.166-1989, Physical Medium Dependent (PMD) -- also ISO 9314-3
* ANSI X3.148-1988, Physical Layer Protocol (PHY) -- also ISO 9314-1
* ANSI X3.139-1987, Media Access Control (MAC) -- also ISO 9314-2
* ANSI X3.229-1994, Station Management (SMT) -- also ISO 9314-6
* ANSI X3.184-1993, Single Mode Fiber Physical Medium Dependent (SMF-PMD) -- also ISO 9314-4
Federal Standard 1037Cand used with permission from http://www.Foldoc.org"
List of device bandwidths
Wikimedia Foundation. 2010.
Look at other dictionaries:
Fiber distributed data interface — Pile de protocoles 7 • Application 6 • Présentation 5 • Session 4 • … Wikipédia en Français
Fiber Distributed Data Interface — Saltar a navegación, búsqueda FDDI (Fiber Distributed Data Interface) es un conjunto de estándares ISO y ANSI para la transmisión de datos en redes de computadoras de área extendida o local (LAN) mediante cable de fibra óptica. Se basa en la… … Wikipedia Español
Fiber Distributed Data Interface — Fiber Distributed Data Interface, FDDI … Universal-Lexikon
Fiber Distributed Data Interface — Dual attach FDDI Board Fiber Distributed Data Interface (FDDI) provides a 100 Mbit/s optical standard for data transmission in a local area network that can extend in range up to 200 kilometers (120 mi). Although FDDI logical topology… … Wikipedia
Fiber Distributed Data Interface — FDDI im TCP/IP‑Protokollstapel: Anwendung HTTP IMAP SMTP DNS … Transport TCP UDP Internet … Deutsch Wikipedia
Fiber Distributed Data Interface — Pile de protocoles 7. Application 6. Présentation 5. Session 4. Tr … Wikipédia en Français
Fiber Distributed Data Interface — En Computación, la FDDI (Fiber distributed data interface) se define como una topología de red local en doble anillo y con soporte físico de fibra óptica. Puede alcanzar velocidades de transmisión de hasta 100 Mbps y utiliza un método de acceso… … Enciclopedia Universal
Fiber Distributed Data Interface — Abbreviated FDDI. The ANSI X3T9.5 specification for fiber optic networks transmitting at a speed of up to 100Mbps over a dual, counter rotating, token ring topology. FDDI s 100Mbps speed is close to the internal speed of most computers, which… … Dictionary of networking
fiber distributed data interface — (FDDI) An ANSI standard for a 100M bps fiber optic LAN using acounter rotating token ring topology … IT glossary of terms, acronyms and abbreviations
Fiber Distributed Data Interface 2 — FDDI 2 im TCP/IP‑Protokollstapel: Anwendung HTTP IMAP SMTP DNS … Transport TCP UDP Internet … Deutsch Wikipedia