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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

261.0. "FDDI on STP" by CGOS01::DMARLOWE (PDP 11: MOV -(PC),-(PC)) Fri May 17 1991 02:45

    I need some help for a customer that needs a little bit of a crystal
    ball.
    
    They are preparing to move into a new office.  It will have lots
    of moveable partitions.  Not unlike our offices. 8^) 8^)  In order
    to accomodate this environment they are getting the partitions prewired
    with power, phone and data.  All this stuff will plug into a box
    in the ceiling called a spider box.  Each spider box will support
    2 sets of connections from partitions.
    
    A wire company has recommended that the data jacks (2 data jacks
    per) be wired with an 8 pair 24 guage wire with an overall tape shield.
    This messes up UTP impedences plus could put multiple data in one
    sheith.  So far we've talked the customer into one 4 pair UTP for
    ETHERNET or low speed.  The question now arises, What do they do
    for FDDI?  They will need FDDI to some desks within a year.  Some
    info I've seen says TYPE 1,2 or 6.  I assume Type 1 and 2 are IBM
    STP.  What is Type 6?  Is it a cheaper TYPE 1 cable?  The customer
    doesn't like the cost of IBM cable.  I wonder why.
    
    The spider box violates EIA/TIA spec as the spider box will have
    AMP connectors so the partition wiring can be quickly unplugged
    for a move.  The only permanant wiring will be the SER to the spider
    box.  This may be fine for RS232/423 and should work fine for ETHERNET
    except for maybe the 100M limit might be reduced somewhat but what
    about FDDI on STP?  Will you be able to use an inline RJ45 in the
    spider box for FDDI on STP?  What type of connector would be on the 
    wall plate for FDDI? And the inline connector in the spider box.

    Any help greatly appreciated as we must get some direction back
    by early next week.
    
    dmm

T.R	Title	User	Personal Name	Date	Lines
261.1	controller connector?	CGOS01::DMARLOWE	PDP 11: MOV -(PC),-(PC)	`Fri May 17 1991 11:11`	5
	It was late and I forgot one question. On the controller there will be a BNC for thinwire but what type of connector is used for STP? dmm
261.2	reply to "what is type 6"	LEVERS::J_HILL		`Mon May 20 1991 11:25`	17
	Lets see, Type 1 cable is fairly standard and comes in non-plenum and more exspensive plenum variety. I believe that, "plenum" refers to fire and safety regulations that exceed those called out for, "non-plenum" varieties. There is also a type 1 riser and type 1 outdoor. As far as I can tell, type 1 is type 1...is type 1. Type 2 is type 1 cable with four voice grade twisted pairs on the outside. Still type 1 cable. Type 6 is often described as, "office" cable. Type 6 is supposed to be, "more" flexible than type 1, the same way some people would argue that a coat hanger is more flexible than a crowbar. Well, I apolagize for the bad analogy. Type 6 is most often used only between the wall plate and end-user, or the patch panel to the rack hardware. Jonathan
261.3	Are You Sure ??	PEACHS::SCHULTZ	Peripheral Visionary...	`Tue May 21 1991 03:56`	10
	We just had the FDDI marketing people here, and STP will be supported by a special adapter card in the DECconcentrator series. Are you sure about the STP messing up Twisted Pair Ethernet impedance? we supported STP with the old style Twisted Pair Adapters (NON-10BASET) and it caused no problems there. I suggest you ask this question in the DELNI::TWISTED_PAIR_ETHERNET conference. MTS
261.4	getting closer	CGOS01::DMARLOWE	PDP 11: MOV -(PC),-(PC)	`Tue May 21 1991 15:07`	17
	It has to be 10BaseT and not 10Base2 on STP/UTP. So that lets out the junk that the wire vendor is pushing. Also 8 pair in a single jacket just encourages the customer to start mixing low, medium and high speed all in the same jacket and with no shielding between any of the signals. About the comments about TYPE 6 wire. Does anyone have a part number either DEC number or Beldon, etc? Also what is the cost compared to IBM TYPE 1? Depending on the cost the customer would like run this for the whole run (not just at the wall plate) instead of TYPE 1. What type of connectors are we looking at on the concentrator? dmm
261.5	DEFCN STP Cu connector	BAGELS::LEVY		`Wed May 22 1991 16:24`	3
	> What type of connectors are we looking at on the concentrator? 9-pin D subminiature.
261.6	length of wire	CGOS01::DMARLOWE	PDP 11: MOV -(PC),-(PC)	`Wed May 22 1991 16:57`	3
	We support TYPE 1 and 2 to 100M. Does the same apply to TYPE 6? dmm
261.7	Hope this helps....	LEVERS::J_HILL		`Thu Jun 06 1991 20:06`	28
	Hi; I'm not the cable guru, but I'll try to do what I can. A good place to start looking at STP cable is the handy ANIXTER catalog. ANIXTER resells alot of stuff for DEC and other vendors, we send them quite a bit of business so they most likely will be willing to help provide quotes. If you don't know ANIXTER, ask around. ANIXTER has industry part numbers. Next, a warning, Type 1 comes in non-plenum and plenum (fire code) varieties. Plenum types can be much more exspensive than non-plenum varieties. I don't know what a cubicle type office would call for, does anyone out there know for sure? Type 1 is a better cable - electrically - than type 6. Type 1 non-plenum is cheaper than type 6. DEC may not support long spans of type 6 cable, but definitely not 100 meters of type 6. //100 meters of type 1 - yes// I doubt there is any support for 100 meters of type 6.// Type 6 is primarily used between the wall plate and some product device. DEC gave out Joyce Radnor's (DTN 226-5096) name as a source of official information. She can probably provide you with more technical information that can be provided to our customers. Jonathan