Fiber Distributed Data Interface 2

from Wikipedia, the free encyclopedia
FDDI-2 in the TCP / IP protocol stack :
application HTTP IMAP SMTP DNS ...
transport TCP UDP
Internet IP ( IPv4 , IPv6 )
Network access FDDI-2

FDDI-2 is a further development of FDDI and is also suitable for the transmission of isochronous data streams (see asynchronous start-stop transmission).

Why FDDI-2

In the synchronous mode of FDDI there are waiting times for the reservation of the bandwidth , whereby the bandwidth can only be guaranteed in connection with a maximum delay . This delay can be with

The order in which the data is sent can also differ from the order in which the data is received ( buffer required). The delay is therefore a maximum of 100 ms, which is an extremely bad prerequisite for a possible dialogue.

development

In 1984 the development of FDDI-2 began with the aim of providing a guaranteed bandwidth with isochronous data streams as an add-on for FDDI. For this purpose, 16 wide band channels (WBC) with 6.144 mbps each were defined.

WBC (Wide Band Channels)

  • The 16 channels may be used individually or combined, and between at least 2 stations for duplex connections are used
  • The WBCs can be isochronous (FDDI-2) or z. B. synchronous (FDDI) can be used
  • If the WBCs are used isochronously (FDDI-2), the data rate can be divided into multiples of 8kbps as a virtual connection (channels with 16, 64, 128, 1536 or 2048kbps)
  • The specific bandwidth is requested via the station management (SMT - see FDDI)
  • The maximum number of WBCs for isochronous traffic is set at the time of initialization

In 1994, FDDI-2 was standardized by the American National Standards Institute (ANSI) and guarantees reliable transport in real time (even with a full video signal and 24 frames per second). FDDI-2 is therefore particularly suitable for the transmission of continuous data. The big problem that FDDI systems cannot be connected to the FDDI-2-LAN contributed significantly to the fact that FDDI-2 was later supplanted by B-ISDN and ATM .

Communication options with FDDI-2

Fddi modi.JPG

literature

  • Dieter Conrads: data communication. Procedure - Networks - Services, 2nd edition, Friedrich Vieweg & Sohn Verlag, Wiesbaden 1989, ISBN 978-3-528-04589-0 .
  • Barry Raveendran Greene, Philip Smith: Cisco ISP Essentials. Cisco System Inc., Indianapolis 2002, ISBN 1-58705-041-2 .
  • Dieter Conrads: Telecommunications. Basics - Procedures - Networks, 5th edition, Friedrich Vieweg & Sohn Verlag, Wiesbaden 2004, ISBN 3-528-44589-0 .
  • Dirk Traeger, Andreas Volk: LAN practice of local networks . Springer Fachmedien, Berlin / Heidelberg, ISBN 978-3-519-06189-2 .
  • Bernhard Albert: FDDI and FDDI-II. Architecture - Protocols and Performance, Artech House, London 1994, ISBN 978-0-89006-633-1 .

Web links