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Conference 7.286::fddi

Title:FDDI - The Next Generation
Moderator:NETCAD::STEFANI
Created:Thu Apr 27 1989
Last Modified:Thu Jun 05 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:2259
Total number of notes:8590

102.0. "FDDI -- 100 miles -- FDDI, how to connect today?" by RIPPLE::KOPEC_ST (Seattle DNT/Sales - DTN 545-4207) Fri Aug 10 1990 15:35

If a customer is sold on our FDDI strategy and implements it at 2 sites 
100 miles apart, is our only option for linking together the 2 sites *TODAY* 
via the following config?
  
 FDDI--DECbridge500--Ethernet--Translan/DECrouter--Ethernet--DECBridge500--FDDI

or...

can the customer work with us today (NWSS, DTAC, etc...) to use a single mode 
FDDI connection BETWEEN the sites even though the standard for single mode is 
incomplete?

If the answer is NO, are there other options?

					Thanks, Stan

T.RTitleUserPersonal
Name
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102.1PSRIPPLE::KOPEC_STSeattle DNT/Sales - DTN 545-4207Fri Aug 10 1990 15:395
    the customer who I am working with is working closely with a local
    telecomm company to have single mode fiber installed between the sites, 
    so if we can't help them somebody else will.
    
    					Thanks again, Stan
102.2KONING::KONINGNI1D @FN42eqFri Aug 10 1990 17:259
I rather doubt that "someone else will".

The total distance limit of FDDI is 200 km.  So unless the fiber happens to
go by the shortest possible route, and that's the only fiber in the entire
ring, you are violating the distance limits.

If you really mean today, then what you've described is about it.  

	paul
102.3RIPPLE::KOPEC_STSeattle DNT/Sales - DTN 545-4207Fri Aug 10 1990 20:4819
    thanks Paul, I didn't realize that the 200 km total distance was
    applicable to both multimode and single mode FDDI implementations.  Since
    there is no standard yet for single mode, I was hoping that single mode
    implementations of FDDI would allow for both...
    	  	a) greater distances between stations/concentrators
    				and..
    		b) greater total distance
                           
    Since (b) is not going to happen, is it correct to assume that single
    mode will allow (a) above?
    
    How about FDDI to T3 bridges?  Is DEC, Vitalink or one of our other
    partners doing research in this area?  Is the research into FDDI-T3
    bridges far enough along to know whether the supported media would
    include both fiber & copper?
    
    					Thanks, Stan
    
                   
102.4some 3rd party capabilityCSOA1::SEITZLOST-IN-SPACESat Aug 11 1990 12:2316
    There are some ways to do this now, or at least in the near future with
    3rd partys. Both cisco and Wellfleet have announced FDDI and T3
    connections for their Router/Bridges. This will allow connectivity
    directly from FDDI to a T3 channel. I believe both products are due to
    be released in the fall.
    
    The second issue, T3 over single-mode fiber has been supplied by the
    local phone companies for years.
    
    I would caution that while these vendors will be providing the
    connectivity between FDDI (100mb) and T3 (45mb), it does not appear
    that their processors will be capable of actually providing such high
    throughput. The last I heard from cisco, they were struggling to
    achieve 15mb in this configuration.
    
    Mike
102.5I have a similar single mode requirementBOSNET::COLUMBUSJOHN COLUMBUSSun Sep 30 1990 20:0920
    I just took a look at your note on single mode FDDI. I'm working
    with the Mass Bay Transit Authority (MBTA) here in Boston researching
    single mode fiber over FDDI options. The MBTA has contracted with
    a metropolitan fiber outfit to use the tunnels and rail lines as
    the right-of-way for fiber routes. As part of this deal, the MBTA
    was given 28 strands back to their operations center from a total
    of 73 buildings throughout the metro Boston area spanning a total
    of 600 miles.
    
    The MBTA wants DEC to discuss single mode over FDDI, along with
    the possibility of two Vax 9000's 2 miles apart connected via FDDI
    Vax clustering. We are in the process of trying to put together
    a non-disclosure with them and get the right engineering people
    out to talk to the MBTA.
    
    I'd like to disuss your progress with your account and share some
    insight with you. I can be reached on BOSNET::COLUMBUS or Columbus@BXO.
    
    John Columbus
    NWSS Consultant