[rescue] FDDI questions

[Julius Sridhar]

On 19 Feb 2002 jwbirdsa at picarefy.com wrote:

> 1) If the MIC connector is also known as the FDDI connector, then why do
> most FDDI cards have SC connectors instead? And why are MIC-SC cables
> so rare? It's easy to find MIC-MIC and MIC-ST, but only perhaps one place
> in four that carries those also has MIC-SC. On the other hand, one of those
> places (www.connectworld.net) has them for a damn good price, $40 for a
> ten-meter cable...

I see MIC->SC all the time.  What I have trouble finding is SC->SC.  Quite
a lot of interfaces are MIC (on things like concentrators).

> 2) Grumping aside, I'm looking forward to setting up an FDDI/CDDI ring.
> I have a Cisco WS-C1100 workgroup stack with eight FDDI SAS MIC, eight CDDI,
> and even a single DAS MIC option installed. Question: since FDDI is a loop
> which passes into and out of each device it's attached to, it seems like it
> should be possible to link two concentrators simply by connecting an
> arbitrary port on one to an arbitrary port on the other -- the loop should
> simply flow through both without any special effort, right? Or is there the
> equivalent of MDI/MDIX, therefore requiring a crossover cable?

As long as you connect the TX of one to the RX of the other, it will work.
Everything in FDDI is a "crossover" configuration.  You are always
connecting the TX of one to the RX of the next.

Peace...  Sridhar