N-GEN Communications Web-based Seminars ©NGCS

Seminar - An Overview of Communications Technologies

Module 7 - LAN, WAN, VPN, WLAN, MAN, FDDI and Optical MANS                                                      Slide 35 of 45 _________________                                                                                  __________

                                         What is a CDDI ?

                                FDDI Implementation Over Twisted Pair Copper Wire

                                Transmission Speed 100 M bps

                                Supports Desktops to Concentrator

                                CDDI Standard

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CDDI is the implementation of FDDI protocols over twisted-pair copper wire.

CDDI supports data rates of 100 M bps. The CDDI standard is defined by ANSI X3T9.5 Committee.

CDDI is a version of FDDI designed to operate on shielded and unshielded twisted-pair cable. CDDI was developed separately by Cabletron and Crescendo. The companies then combined their technology work and received ANSI standards approval in 1993. A typical CDDI network consists of concentrators with a number of ports for the connection of workstations. Because CDDI has limited cable distances, a CDDI concentrator can connect to an FDDI ring as a subnetwork.