Conference 7.286::fddi

1117.0. "Copper FDDI Standards update" by LEVERS::B_CRONIN () Mon Oct 18 1993 11:32

    The copper FDDI committee is in the final stretches of producing the 
    standard for FDDI over UTP and STP. If all goes well, we expect to send
    the document to ballot at the December FDDI standards meeting. 
    
    The correct name for this standard is Twisted Pair PMD (TP-PMD). 
    
    The details are still pretty much the same as in my prior postings:
    
    a) support for category 5 UTP and 150 ohm STP
    b) scrambled MLT-3 coding
    c) 100 meter link distances
    d) uses same SMT as optical products
    e) 2 volt p-p transmit level into 100 ohms, slightly more into 150 ohms
    
    Early versions of standards based products have been demonstrated at the 
    recent series of interoperability demos (Boston, Interop in August, 
    Interop in Paris). There are approximately 25 vendors who have taken part 
    in these demos. Many are shipping product today. As always, a standard is 
    not a standard until it is approved, so product in advance of a standard 
    is always subject to change. 
    
    Digital has participated in these demos, showing EISA cards and a 6
    port concentrator for the DECHub 900. The EISA card is a UTP version of
    the same design that has received excellent reviews in recent Network
    Computing and PC Week articles. Also, make sure to see the recent
    edition of Data Communications which is strongly in support of FDDI. 
    which has received