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Conference netcad::hub_mgnt

Title:DEChub/HUBwatch/PROBEwatch CONFERENCE
Notice:Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7
Moderator:NETCAD::COLELLADT
Created:Wed Nov 13 1991
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:4455
Total number of notes:16761

923.0. "SMF and concentrator 900MX, DEFXS, DEF6*, help!!!" by DECPRG::PAVLUP () Fri Apr 22 1994 05:12

Give me anyone som more information, please. I found in a general information
mail an info about ssome current restrictions on SMF PMDs for DECconcentrator
900MX:

> Configuration Restrictions - There is an issue with Single Mode Fibre in the
> DECconcentrators and the DEF6A and DEF6B are temporary solutions for
> supporting Single Mode Fibre. The DEFXS that is shipping has restrictions in
> the concentrator in that we can't populate all the ports due to mechanical
> issues. The redesigned SMF mod PMD will ship in Q1FY95.  So in the meantime
> if someone needs SMF they need to order:
>
>        DEF6A - SMF in Port 1 (which can be A or M) and MMF in ports 3-6
>                (Port 2 has no mod PMD)
>        DEF6B - SMF in Port 6 (which can be B or M) and MMF in ports 1-4
>                (Port 5 has no mod PMD)
>
> These will be deleted as part numbers once we start shipping the new DEFXS.

What is the situation, how long it will last, and do we have any other options?
I'm asking because we sold 3 concentrators to a customer just for connecting
his sites to a SMF FDDI ring!!! We had rather a hard days to win  a 0.5M deal 
just in networking! So seeing this really does frighten me.

Not only that a half/SMF solution is not enough for our configuration but 
also the options with almost fully populated PMDs (moreover with all MMFs) are
not flexible at all (in our case we need only two PMDs in each concentrator
apart from the SMF ones...).

Please, put some info here or to me, or point me somewhere for additional
info or a real solution!

You can imagine that the matter is urgent.

Thanks Petr

DECPRG::PAVLUP
Petr Pavlu @CHK
T.RTitleUserPersonal
Name		DateLines
923.1interim single mode modpmd solution for def6xLEVERS::IANNARONEMon Apr 25 1994 14:2625
    The new single mode module will be available sometime this summer.  At
    this time it's very hard to say exactly when, however.  The existing
    part has a few feet of fiber optic cable that must be treated somewhat
    carefully due to bend radius requirements.  In the DEF6X, room is VERY
    tight, and in order to guarantee that the cable didn't get kinked, we
    decided to have it preconfigured at the factory, with the intent of
    having the new version available very shortly.  Unfortunately, we ran
    into some problems with the new single mode module, so it's not
    available as soon as we had hoped.  
    
    You can install 2 of the existing single mode cards provided you leave
    an adjacent slot empty.  this emply space is needed to put the windings
    of fiber optic cable.  In addition, you must be careful NOT to put any
    significant bends in the cable that would violate the 1 inch bend
    radius.  If you populate ports 1 and 6 with single mode, you can put 2
    other modpmds in  ports 3 and 4.  In this way, ports 2 and 5 are left
    open, and the extra fiber optic cable should be coiled in these spaces.
    
    Hopefully, the new single mode solution will be available (it should
    have no port or usage restrictions) before many other folks run into a
    problem similar to yours...
    
    
    Regards,
    John
923.2SMF and def6xDELNI::ROUNDSMon Apr 25 1994 17:5623
From:	DELNI::ONEILL       "SHARON O'NEILL | 226-5112 | LKG2-1/Z3" 25-APR-1994 16:45:14.57
To:	DECPRG::PAVLUP
CC:	MIKES,JOHNI,ONEILL
Subj:	SMF and concentrator

The current plan is to ship the new SMF DEFXS-BA in Q1.  This requires that 
we complete regulatory testing (ESD, FCC, PTT, etc.).  The issue with the
current DEFXS-AA is a mechanical problem - there is a large loop of fiberoptic
cable on this modPMD which bends when you put the modules back into the
concentrator enclosure.  Since the cable is glass, it breaks.

I reviewed the typical confurations from the DECconcentrator 500 for SMF 
which is what I based the DEF6A and DEF6B.  There is nothing to prevent 
you from trying to configure on your own - but it is not without risk and we
don't support it.  If customer can wait until Q1, you'd be better off.
At this time there is no trade-in program planned (but being addressed).

Help me understand what this customer's configuration is. 

Sharon
.................